What’s Up This Week – Feb 27 – Mar 6, 2005

Image credit: NOAO/AURA/NSF
Monday, February 28 – Let’s start tonight enjoying the early dark skies and go to our maps west of the M36 and M38 to identify AE Aurigae. As an unusual variable, AE is normally around 6th magnitude and resides approximately 1600 light years distant. The beauty in this region is not particularly the star itself but a faint nebula in which it resides known as IC 405, an area of mostly dust and very little gas. What makes this view so entertaining is that we are looking at a “runaway” star. It is believed that AE once originated from the M42 region in Orion. Cruising along at a very respectable speed of 80 miles per second, AE flew the “stellar nest” some 2.7 million years ago! Although the IC 405 is not directly related to AE, there is evidence within the nebula that areas have been cleared of their dust by the rapid northward motion of the star. AE’s hot, blue illumination and high energy photons fuel what little gas is contained within the region as well as reflects off the surrounding dust. Although we cannot “see” with our eyes like a photograph, together the pair form an outstanding view for the small backyard telescope and it is known as “The Flaming Star.”

Tuesday, March 1 – George Abell was born on this day in 1927. Abell was the man responsible for cataloging 2712 clusters of galaxies done with the Palomar sky survey completed in 1958. Using these plates, Abell put forth the idea that the grouping of such clusters distinguished the arrangement of matter in the universe. He developed the “luminosity function”, which shows relationship with brightness and number of members in each cluster, giving rise to distances. Abell also discovered a number of planetary nebulae and developed the theory (along with Peter Goldreich) of their evolution from red giants. Mr. Abell was a fascinating lecturer and a developer in many television series dedicated to explaining science and astronomy in a fun and easy to understand format. Abell was also a president and member of the Board of Directors for the Astronomical Society of the Pacific, as well as serving on the American Astronomical Society, Cosmology Commission of the International Astronomical Union, and accepted editorship of the Astronomical Journal just before he died.

Would you like to study an Abell galaxy cluster? Then let me sweep you away to Abell 426 just two degrees east of previous study star – Algol. I caution you that this is not an area that can be seen with the average telescope, but for those of you with very large aperture you will find a study region incredibly worth your time and attention. The brightest of this group of galaxies in the NGC 1275 at magnitude 12.7. As an incredible radio source, the NGC 1275 is thought to be two galaxies actually in the process of passing through one another. Depending upon both your seeing conditions and aperture, Abell 426 may reveal anywhere from 10 to 24 small galaxies that range to close to magnitude 15. Given the fact that there are around 233 galaxies in this cluster alone, it’s a privilege to be able to spot a few!

Abell 426 has been a longstanding favourite of mine. It is a curious galaxy cluster in the respect that the finer the night, the more galaxies will reveal themselves. The first study lays right in the field with a star and the NGC 1224 requires wide aversion. It is faint, round, and shows some concentration toward the nucleus with patience. Held indirect, this small galaxy has a UGC-like signature. Next stop on the hop is the NGC 1250 which is very diffuse, small and requires wide aversion. While allowing the eye to bounce around the field, it is possible to make out a slight north/south tilt to this galaxy that may indicate it to be a spiral. Curiously enough, it is during this motion that a pinprick of a nucleus can be detected. Pushing on toward the heart of the Perseus Galaxy cluster, the next destination is a chain of three. First study mark is the NGC 1259. Extreme aversion only… Very, very diffuse and faint, it can only be caught by focusing attention on the tiny star in the westward drift. The NGC 1260 only requires slight aversion, however. It is small and somewhat diffuse – definitely ovoid in structure – as well as the easiest to see of these three! The NGC 1264 also requires very wide aversion. Very faint and diffuse, very round – and very challenging! Now, triangulating with this series, it’s time to go for the NGC 1257 – very faint, diffuse and small with a concentration toward the core, it holds a little surprise – there’s a tiny star at the northeast end that allows one to see upon wide aversion that the galaxy itself seems to migrate to the northeast/southwest.

From here we have the option of continuing on the same trajectory or doing a lateral “move”. Past experience dictates that maps don’t always reveal everything there is to be seen in such a cluster including galaxies that masquerade as stars. The “heart” of Abell 426 is so dense that identification is extremely difficult! The NGC 1271 skirts the most populated part of this Abell cluster and requires super wide aversion to detect a very faint, very small patch that is barely visible. Even experience can draw nothing more than a slightly regular contrast change in this area. Next up is an extremely challenging triple – the NGC 1267, NGC 1268 and NGC 1269 are three incredibly tiny, very diffuse round gems that would be totally indistinguishable at lower power. NGC 1273 is faint – it requires aversion, but the brighter core region holds up to indirect vision. The NGC 1272 is also round – almost planetary in appearance. The NGC 1270 is very diffuse and takes wide aversion. It contains a very small, almost stellar nucleus. NGC 1279 is faint, diffuse, and stretches just ever so slightly, like a thin smear held at slight aversion to the north/south. It is even with no nucleus present. The NGC 1274 is very faint and very diffuse, even, and is best seen while concentrating on the NGC 1279 – revealing an incredibly small, misty oval. The NGC 1275 is very bright compared to all the previous studies. It most definitely has a bright and easily held direct nucleus. Going for a pair, we find the NGC 1282 to be diffuse, slight in size and quite ovoid – very even in structure with no hint of a nucleus even a full avert. The companion, NGC 1283, is very diffuse and we probably couldn’t see it except for there are some small field stars that triangulate in this area that leads to its foggy apppearance. Now for the NGC 1294 and NGC 1293 – wide aversion shows two round fuzzies with prickly nucleus structure. The pair looks like two impossibly small dandelions waiting to be scattered on the cosmic winds…

Best of luck on your Abell quest!

Wednesday, March 2 – How about tonight if we relax a bit and look for an open cluster that is viewable in binoculars and small scopes for the majority of both the northern and southern hemispheres? Our marker for this hop will be Xi Puppis and you will find M93 approximately two finger-widths (two degrees) northwest and almost right on the galactic equator.

Cataloged by Charles Messier in March of 1781, this wonderfully bright grouping (overall magnitude 7) of around 80 stars contains a wealth of various stars types that are roughly around 3400 to 3600 light years away. In binoculars the view is incredibly rich, but a telescope adds so much more! Towards the center, the viewer will note a wedge-shaped collection. At the heart of this is an easy double star and another on the western edge. The very brightest of these stars are young, hot and blue with a stellar population quite similar to the Plieades. How old you ask? A very modest one million years….

Thursday, March 3 – Get up early! There will be occultations galore for North America! Starting with the east coast, the Moon will occult Sigma Scorpii in the wee hours. Check out IOTA for specifics. On a broader note, (and the same morning!) the Moon will also occult Antares just a few hours later. It doesn’t matter if you are not into critical timing, you really should take advantage of this opportunity. Watching this kind of event is incredibly inspiring – even if you just view it with your eyes!

Tonight let’s try something a bit different! We’ll be heading about a degree and a half south/southwest of Alpha Monocerotis to find a magnitude 10 open cluster known as Melotte 72. Achievable in a good 6 to 10 inch scope, this loose collection of around 50 or so stars appears in a wonderful “delta wing” pattern! Continuing another degree and a half south will bring you to 7th magnitude Melotte 71. Easily capturable in the small scope, this unique small cluster contains around 100 stars. Remember where you found them, for this will be our guide to other studies!

Friday, March 4 – In 1835, Giovanni Schiaparelli opened his eyes for the very first time and opened ours with his accomplishments! As the director of the Milan Observatory, Schiaparelli (and not Perceval Lowell) was the fellow who popularized the term “Martian canals” somewhere around the year 1877. Far more importantly, Schiaparelli was the man who made the connection between the orbits of meteoroid streams and the orbits of comets almost eleven years earlier!

How about if we take a look at some comets tonight?

C/2004 Q2 Machholz is still holding strong and still viewable with just binoculars. Happily turning around Polaris, the “Magnificent Machholz” will be quite near the Cepheus/Camelopardalis border. C/2003 K4 LINEAR is still within large binocular range and can be found north of Tau 5 Eridanus. C/2005 A1 LINEAR makes a spectacular morning appearance for the small scope just south of Alpha Apus. In the north, comet C/2003 T4 LINEAR should have brightened to magnitude 9 and be very near Kappa Delphini in the hours before dawn. 141P/Machholz scoots into Aquarius for those around 40 degrees just after sunset, but will be a challenge at magnitude 10. Break out the big scopes and see if you can pick out 12th magnitude 78P/Gehrels so close to Theta 1 and Theta 2 Tauri… And since you’ve got the power out, take a look at 32P Comas/Sola just a few degrees from the Plieades!

Saturday, March 5 – Today is the birthday of Gerardus Mercator, famed mapmaker, who started his life in 1512. Mercator’s time was a rough one for astronomy, but despite a prison sentence and the threat of torture and death for his “beliefs”, he went on to design a celestial globe in the year 1551. If you are up early this morning, you can see the lunar feature named for Gerardus! While the most prominent crater of all will be Gassendi, we will use it as our starting point and head south. The dark expanse of Mare Humorum comes next and south of it and on the terminator you will find a heart-shaped area known as Palus Epidemiarum. On its northern shore you will see the outlined circle of crater Campanus. On this crater’s southeast border and mostly shadowed is the remains of Mercator!

Tonight let’s head back to Alpha Monocerotis. Remembering our “drop” for Mel 71 and 72, continue south about 2 more degrees. In the finderscope, you will see an L-shaped collection of 4 stars. Going to the eyepiece at low power – wide field, you are in for a double treat as we view two open clusters. The northernmost is NGC 2423, but the most interesting (and bright!) is more commonly known as M47.

M47 was known long before Messier’s time because it approaches unaided eye visibility. When Charles discovered this 5th magnitude beauty February 19, 1771 he described it as a brighter neighbor of the M46, but incorrectly logged its position! Thus was born the “missing Messier” until 1934 when Oswald Thomas identified it. It’s rather funny to note that because of a “messy mistake” that William Herschel also discovered it some fourteen years later! Even the later Herschel and Dreyer had problems with this one… But you won’t have any problems as you view this bright cluster in either binoculars or telescope! It is a loose open cluster around 78 million years old that contains around 50 stars of various magnitudes in a region about the same size of the full moon. At roughly 1600 light years away, you might even get a glimpse of an orange giant or two, along with beautiful double Sigma 1121 in its center!

Sunday, March 6 – Although almost no one likes to get up early on a Sunday morning, set your alarm for around 5:00 am. and carpe diem! This morning the splendid remaining crescent of the Moon will put on a spectacular showing called a “conjunction” with the Red Planet – Mars! You’ll find the stars of summer have quietly moved since since we viewed them last and Mars is now in Sagittarius. Shining every bit as brilliant as its namesake, Antares, Mars will be just a bit more than a fist’s width (6 degrees) above the Moon. Don’t miss it!

If you get a chance to see sunshine today, then celebrate the birthday of Joseph Fraunhofer who was born in 1787. As a German scientist, Fraunhofer was truly a “trailblazer” in terms of modern astronomy. His field? Spectroscopy! After having served his apprenticeship as a lens and mirror maker, Fraunhofer went on to develop scientific instruments, specializing in applied optics. While designing the achromatic objective lens for the telescope, he was watching the spectrum of solar light passing through a thin slit and saw the dark lines which make up the “rainbow bar code”. Fraunhofer knew that some of these lines could be used as a wavelength “standard” so he began measuring. The most prominent of the lines he labeled with letters that are still in use today! His skill between optics, mathematics and physics led Fraunhofer to design and build the very first diffraction grating which was capable of measuring the wavelengths of specific colors and dark lines in his solar spectrum. Did his telescope designs succeed? Of course! His work with the achromatic objective lens is the design still used in modern telescopes!

And for our “pasta resistance” of the week? Let’s head right back to the area we’ve been studying and go about a degree and a half east/south east of the M47. Tonight we’ll be studying an object that once again is viewable to most of the northern and southern hemisphere and is bright enough to be caught in binoculars. Its name? M46!

Discovered on February 19, 1771 by Charles Messier, the M46 opened a new chapter for our hero as he had just published his first list. At a visual magnitude of 6, this rich galactic cluster could contain up to 500 members and is around 300 million years old. Slightly smaller than a lunar diameter, it will appear as a “dust ball” (along with the M47) to binoculars, but holds a wonderful surprise for the telescope! On its northern border is a “bright star” which under power turns into planetary nebula, NGC 2438. Is it actually part of the M46? Well, science thinks not. The planetary nebula is actually receding far faster than the stars around it. On the average, the M46’s distance is about 4600 light years, while the nebula is around 2900. The planetary itself takes more than a billion years to reach this point in evolution and our stellar “swarm” just isn’t quite that old! No matter how we “slice and dice” this particular deep sky object, the fact remains… We get two for the price of one! Two Messiers in the field for binoculars – and two DSOs in the field of view for telescopes!

Hey! Isn’t it great to enjoy dark skies again? I love the Moon, but there’s no place like space! Until next week? May all your journeys be at light speed! … ~Tammy Plotner

What’s Up This Week – Feb 21 – 27, 2005

M 41 credit: NOAO/AURA/NSF
Monday, February 21 – Tonight let’s head four degrees south of the incredible Sirius and locate an easy binocular or telescope object – M 41. Noted as early as 325 B.C. by Aristotle – and cataloged by Messier in 1765, the M 41 is a beautiful, loose, looping collection of around two dozen bright stars and many more faint members that range with aperture. At around 2,300 light years away, it’s remarkable we can see it at all! Spanning approximately 25 light years, it is estimated this cluster could be as much as 240 million years old. Although the presence of the Moon will harm some of its fainter members, the M 41 sports many red “giant” stars – especially the one in the center!

Now, let’s have a look at the Moon and identify a new crater. Near the terminator and south of Mare Humorum you will find a very notable walled plain known as Schickard. While it doesn’t appear to be much, Schickard is almost as large as the Netherlands! Notice its bright white wall underscored with shadow along the northeast inner wall. Schickard is an unusual crater because of its curvature – it’s convex! At its center, the walled plain is just a little bit more than 213 meters (700 feet) higher than the area at the edges. If you were standing in the middle of this crater and scanning the horizon, you could never see the walls!

Tuesday, February 22 – Since the Moon will dominate the evening sky, let’s start by observing and identifying an “on the edge” feature. Return to previous study area, Sinus Iridum and head north! Near the terminator you will see a slender, bright ellipse with a bright northwest wall and a dark southeast wall. This is the deep, walled plain of class one Pythagoras. Note the bright twin central peak that rises around 1829 meters (6000 feet) high. Considering the angle that we see this area from, that type of elevation is comparable to the height of El Cielo – Mexico’s “Cloud Forest”!

And while we have our head in the clouds, let’s have a look at the eighth brightest star in the sky – Procyon. At around 11.3 light years away from us, the “Little Dog Star” is the fifth nearest star to Earth. It is well known that Procyon is a double star – but that’s a challenge beyond the ordinary backyard scope. Very much like Sirius, the 13th magnitude companion is also a dwarf star – one that’s about twice the size of our Earth!

Wednesday, February 23 – Although the Moon appears full tonight, it’s just not official. According to folklore, this is known as both the “Snow Moon” and the “Storm Moon”… Let’s hope that doesn’t mean certain areas of the world are about to get buried again! Tonight let’s have a look at Selene with either binoculars or telescope. We are looking for the pale, shallow form of Langrenus on the eastern edge of Mare Fecunditatis. It won’t appear very impressive tonight, but let’s see how much it changes in 48 hours!

With incredibly bright skies tonight, let’s turn a little attention toward the dominant star in Auriga – Capella. As the sixth brightest star in the sky, lovely yellow Capella is around 45 light years away. As with most stars, the “Goat” is actually a multiple system! Although its members are too close to be split with average equipment, if skies are steady you might be able to glimpse 10th magnitude red dwarf – Capella H – toward the southeast!

Thursday, February 24 – It’s official… Full Moon at 4:54 UT! Tonight let’s scan the western limb of the Moon and look for the Cordillera Mountains south of Grimaldi. Although this will appear as nothing more than a rough edge, we do this so we may see the effects of lunar libration. Remember what you see… We’ll be back in two days.

And speaking of two, let’s try our hand at Rigel tonight . As you may have noticed for the most part – the brighter the stars are – the closer they are. Not so Rigel! As the seventh brightest star in the sky, it breaks all the “rules” by being an amazing 900 light years away! Can you imagine what an awesome supergiant this white hot star really is? Rigel is actually one of the most luminous stars in our galaxy and if it were as close as Sirius it would be 20% as bright as tonight’s Moon! As an added bonus, most average backyard telescopes can also reveal Rigel’s 6.7 magnitude blue companion star. And if these “two” aren’t enough – note the companion is also a spectroscopic double!

Friday, February 25 – Before the rising Moon interferes tonight, let’s have a go at C/2003 K4 LINEAR. At around magnitude 9, this small comet will be fairly easy to locate telescopically just west of Tau 3 Eridanus.

Let’s return to the Moon tonight to have another look at class 1 crater Langrenus. What a difference! Instead of the bright ring we saw two nights ago, Langrenus is now alive with detail. With the lunar terminator just to its east, we can now see its dual central mountain. Just outside of the crater rim to the northwest, a cluster of three tiny punctuations are revealed – Langrenus F (Bilharz), B (Naonobu) and K (Atwood). Look for tiny crater Acosta just to the north, and Lohse to the south!

Saturday, February 26 – For those living in time zones where 13:00 UT (5:00 a.m. PST) presents you with an opportunity to look at the moon, the libration will now be correct for Mare Oriental. Return to the Cordillera Mountains south of Grimaldi and see if the extra 5.7 degrees of shift reveals the dark edge of this seldom seen area!

Tonight Atlas and Hercules will steal the lunar show to the north, but let’s head to the south and identify class crater Rheita on the terminator. Although the crater itself is not terribly impressive, look closely at its west rim. You will pick up on a very noticeable black streak with a bright edge to the east. This is the Rheita Valley, and much older than the crater which bears its name! It curves slightly south-east towards the terminator and it is believed to be a chain of craters which have merged ending in larger crater Young.

Sunday, February 27 – Heads up for Southern Australia! The Moon will occult Jupiter for you on this universal date. Please check IOTA for the viewing area and universal timing. We wish all of you clear skies for this awesome event!!

If the Sun is shining today in the northern hemisphere, have a look at your “marker” that we picked at solstice. You’ll see its shadow is one-third shorter!

And for those in the north, Comet Machholz is still putting on a wonderful display as it has become a circumpolar object. Before “you know who” decides to light up the night sky, try looking east of Gamma Cepheus. By this time, the “Magnificent Machholz” with be approaching magnitude 6, but it will still be a great object even for small binoculars!

As we visit the Moon again tonight, we will be looking a rather prominent feature south of Mare Nectaris – Piccolomini. In bold black and white relief, you can’t miss this small crater’s striking central peak!

Until next week, remember Saturn and Jupiter also are wonderful things to look at during “moonshine”, and don’t forget double stars! Me? I’m looking forward to dark skies again! Light speed… ~Tammy Plotner

What’s Up This Week – Feb 14 – 20, 2005

Monday, February 14 – Happy Valentine’s Day! One of the more unusual and ephemeral objects for the northern sky is the elusive IC 1805 – known as the “Heart” nebula in Cassiopeia. Thanks to the presence of the Moon and the constellation’s position, viewing the IC 1805 will be next to impossible, but you can still challenge yourself to Mel 15, the 7th magnitude star cluster associated with the “Heart”. Remember its position for a night with clear, dark skies. The IC 1805 will be your “Valentine” for years to come. You see? Even the stars can hold surprises!

And what could be more romantic than a moonlit evening? Why not take out a scope and tonight let’s study dorsa! Along the terminator you will see 75% of Mare Tranquillitatis, joined at its northern edge by the beginnings of Mare Serenitatis. It is here that you will find our “marker” – the ancient walled plain Posidonius. Inside Serenitatis and running parallel with the terminator are the snake-like lines of the Dorsa Smirnov – a beautiful collection of wrinkle ridges known as “dorsa”. To the south look for the “three ring circus” of craters Theophilus, Cyrillus and Catharina. Focus your attention on the sunlit Mare Nectaris. Cutting across it between Theophilus in the north, and shallow open crater Beaumont in the south you will see a thin, bright line. Congratulations! You have just spotted an officially “unnamed” lunar feature that is often referred to as Dorsa Beaumont.

Very cool…

Tuesday, February 15 – Happy 441st Birthday to Galileo Galilei! He was the first scientist to use a telescope for astronomical observation. I wonder if Galileo could have ever dreamed when he first saw the Moon that mankind would one day walk on its surface? Let’s celebrate his achievements by a look into lunar history…

Tonight, all of Mare Tranquillitatis, and the majority of Mare Serenitatis will be revealed just north of the terminator’s mid-point. On the northwestern shore of Serenitatis, you will see the eastern portion Caucasus Mountains emerging in the sunlight. Tonight let us take an historic journey to the southwest edge of Tranquillitatis and visit with the Apollo 11 landing area. Although we can never see the “Eagle” telescopically, we can find where it landed! Tracing along the western wall, look for the small circles of craters Sabine and Ritter. Once you have located them, go to your highest power! To the east in the smooth sands you will see a parallel line of three tiny craters. From west to east, these are Aldrin, Collins and Armstrong – the only craters to be named for the living! It is just south of these three tiny punctuations that Apollo 11 touched down, forever changing our perceptions of space exploration.

Galileo would have been proud!

Sunday, February 26 – Fran?ois Jean Dominique Arago was born on this day in 1786. Arago was the pioneer scientist in the wave nature of light and the inventor of the polarimeter and other optical devices. In February 1948, Gerard Kuiper discovered Uranus’s moon, Miranda. And speaking of moons, did you see Selene during the daylight today? Spectacular, isn’t it? Have you ever wondered if there was any place on the lunar surface that has not seen the light? Then let’s go exploring for one tonight…

Our first order of business will be to identify crater Albategnius. Directly in the center of the Moon is a dark floored area known as the Sinus Medii. South of it will be two conspicuously large craters – Hipparchus to the north and ancient Albategnius to the south. Trace along the terminator toward the south until you have almost reached its point (cusp) and you will see a black oval. This normal looking crater with the brilliant west wall is equally ancient crater Curtius. Because of its high latitude, we shall never see the interior of this crater – and neither has the Sun! It is believed that the inner walls are quite steep and the crater Curtius’ interior has never been illuminated since its formation billions of years ago. Because it has remained dark, we can speculate that there may be “lunar ice” pocketed inside its many cracks and rilles that date back to the Moon’s formation!

Because our Moon has no atmosphere, the entire surface is exposed to the vacuum of space. When sunlit, the surface reaches up to 385 K, so any exposed “ice” would vaporize and be lost because the Moon’s gravity cannot hold it. The only way for “ice” to exist would be in a permanently shadowed area. Near Curtius is the Moon’s south pole and Clementine imaging showed around 15,000 square kilometers of area where such conditions could exist. So where did this “ice” come from? The lunar surface never ceases to be pelted by meteorites – most of which contain water ice. As we know, many craters were formed by just such an impact. Once hidden from the sunlight, this “ice” could go on to exist for millions of years!

Thursday, February 17 – So… would you like to do a little lunar “prospecting” tonight? Then let’s explore a crater similar to last night’s Curtius. In the north, identify previous study crater Plato. North of Plato you will see a long horizontal area of gray floor – Mare Frigoris. North of it you will note a “double crater”. This is elongated diamond-shape is Goldschmidt and the crater which cuts across its western border is Anaxagoras. The lunar “north pole” isn’t far from Goldschmidt and since Anaxagoras is just about one degree outside of the Moon’s theoretical “arctic” area, the lunar sunrise will never go high enough to clear the southernmost rim. As proposed with yesterday’s study, this “permanent darkness” must mean there is ice! For that very reason, NASA’s Lunar Prospector probe was sent to explore. Did it find what it was looking for? Answer – Yes!

The probe discovered vast quantities of cometary ice which have hidden inside the crater’s depths untouched for millions of years. If this sounds rather boring to you, then realize this type of resource will colour our plans to eventually establish a manned “base” on the lunar surface! On March 5, 1998 NASA announced that Lunar Prospector’s neutron spectrometer data showed that water ice was discovered at both lunar poles. The first results showed the “ice” mixed in with lunar regolith (soil, rocks and dust), but long term data confirmed near pure pockets hidden beneath about 40 cm of surface material – with the results being strongest in the northern polar region. It is estimated there may be as much as 6 trillion kg (6.6 billion tons) of this valuable resource! If this still doesn’t get your motor running, then realize we can never establish a manned lunar base because of the tremendous expense involved in transporting our most basic human need – water. The presence of lunar water could also mean a source of oxygen, another vital material we need to survive! And if we wanted to return home or onward, these same deposits could provide hydrogen which could be used as rocket fuel. So as you view Anaxagoras tonight, realize that you may be viewing one of mankind’s future “homes” on a distant world!

Friday, February 18 – Today in 1930 Clyde Tombaugh discovered Pluto during a search with photographic plates taken on the Lowell Observatory’s 13″ telescope. Although we might not make such a monumental contribution, we can still do a little “mountain climbing”! Tonight the most outstanding feature on the Moon will be Copernicus, but since we’ve delved into the deepest areas of the lunar surface, why not climb to some of its peaks?

Using Copernicus as our guide, to the north and northwest of this ancient crater lay the Carpathian Mountains ringing the southern edge of the Mare Imbrium. As you can see, they begin well east of the terminator, but look into the shadow! Extending some 40 km (25 miles) beyond the line of daylight, you will continue to see bright peaks – some of which reach 2072 meters (6600 feet) high! When the area is fully revealed tomorrow, you will see the Carpathian Mountains eventually disappear into the lava flow that once formed them. Continuing onward to Plato, which sits on the northern shore of Imbrium, we will look for the singular peak of Pico. It is between Plato and Mons Pico that you will find the scattered peaks of the Teneriffe Mountains. It is possible that these are the remnants of much taller summits of a once stronger range, but only around 1890 meters (6200 feet) still survives above the surface. Time to power up! To the west of the Teneriffes, and very near the terminator, you will see a narrow “pass” cut through the region, very similar to the Alpine Valley. This is known as the Straight Range and some of its peaks reach up to 2072 meters (6600 feet)! Although this doesn’t sound particularly impressive, that’s over twice as tall as the Vosges Mountains in central western Europe and on the average very comparable to the Appalachian Mountains in the eastern United States. Not bad!

Saturday, February 19 – Nicholas Copernicus was born on this day in 1473. Copernicus advanced our understanding of earth’s relation to the motions of the solar system. He was a man who could see the “big picture”!

Tonight let’s continue our Moon mountain climbing expedition and look at the “big picture” on the lunar surface. Tonight all of Mare Imbrium is bathed in sunlight and we can truly see its shape. Appearing as a featureless ellipse bordered by mountain ranges, let’s identify them again. Starting at Plato and moving east to south to west you will find the Alps, the Caucasus, the Apennine and the Carpathians mountains. Look at the form closely… Doesn’t this appear that perhaps once upon a time an enormous impact created the entire area? Compare it to the younger Sinus Iridium. Ringed by the Juras Mountains, it may have also been formed by a much later and very similar impact.

And you thought they were just mountains…

Sunday, February 20 – Today in 1962 John Glenn became the first American to orbit the Earth three times aboard Friendship 7. Only 32 years later, the Clementine Lunar Explorer also went in orbit – but this time around the Moon! Let’s get out the scopes…

Tonight’s most prominent lunar feature will be the graceful Gassendi towards the south, but it is a crater in the Oceanus Procellarum that we will be studying tonight. Within the “Ocean of Storms” you will find the bright point of Class 1 crater Kepler, just slightly above the terminator. The sprawling Oceanus Procellarum has low reflectivity (albedo) because the mare lavas are primarily dark minerals like iron and magnesium. Bright young Kepler (32 km/2.6 km) will show a wonderfully developing ray system, but there is so much information there! The very hills that Kepler’s initial impact drove into are part of the Alpes Formation – the inner ejecta from the Imbrium area which we noted last night. At high power you will see that the hills themselves have been filled with lava flow before Kepler was formed. The crater rim itself is very bright, consisting mostly of a pale mineral called anorthosite. The lunar rays extending from Kepler are anorthosite fragments that literally were splashed out and flung across the lunar surface during the impact that formed this crater. The region is also home to lunar feature known as “domes” – seen between the crater and the Carpathian Mountains. So unique is Kepler’s geological formation that it became the first crater to mapped by U.S. Geological Survey in 1962. This fantastic chart was labeled I-355 and was the work of R.J. Hackman.

Kepler… Not just another boring crater!

Until next week? “May you all shine on… like the Moon, the stars, and the Sun…”

May your journey be at light speed! ~Tammy Plotner

What’s Up This Week – Feb 7 – 13, 2005

Monday, February 7 – Tonight let’s start with a wonderful binocular or low power richfield telescope object. Located just east of the Cassiopeia border into Camelopardalis is a beautiful chain of around 20 colorful stars that stretch over five moon widths across the sky. This delightful asterism of stellar jewels was made popular by amateur astronomer Lucian Kemble, and are known in his memory as “Kemble’s Cascade”. Although the stars are really not related to one another, they create an outstandingly picturesque image with the stars in a line and tiny open cluster NGC 1502 connected to the end.

Now that we’ve got a “line” let’s get out the scopes and go fishing in Pisces tonight! We’re heading for Gamma Arietis, and drawing a mental line between it and Eta. Approximately two-thirds of the way is the spectacular M74. This is a by-gosh spiral galaxy! Its “rolled” structure becomes immediately apparent in mid to large telescopes. The outstanding core area is intense and the arms twist away from it quite tightly. It sports several areas of bright clusters/nebulosity – and as it twists away into space, two lovely spiral arms reach right out and wrap themselves around it. Very similar the “Whirlpool” (M51), the “galactic stuff” wisps away at the edges where several bright stars play the field with it. This is one exceptionally pretty galaxy!

Tuesday, February 8 – Hey, hey, hey… It’s “Fat Tuesday”! Why not begin the day by scoring a binocular trophy? You’ll find that Mars is wonderfully positioned between the M20 and M8! Even the skies will be celebrating tonight as the Moon officially goes new at 12:12 UT. Since we will have dark skies for the next couple of days, let’s do some challenge studies!

Tonight we’ll be hunting that “wascally wabbit” Lepus. One of the finest pieces of work in this area is our previous study – globular cluster, M79. It is not the most brilliant of small globulars that I have seen, but at higher magnification in larger scopes the outer stars begin to resolve, making it quite pretty. Another faint fuzzy to be found in Lepus is spiral galaxy, NGC 1964. Again, not the most awe inspiring one I’ve ever traveled to, but with patience and steady sky, some brightenings around the outer edge of the central structure begin to show making it worth the hunt! Also take the time to re-visit R Leporis – Hind’s “Crimson Star”. It sits below Rigel and is a very deep red like Mu Cephii.

As the skies move westward, we head next to Canis Major. By locating Beta, this galaxy drop is fairly simple by continuing on a basic southern trajectory working the “fall line” one field of view at a time from west to east. Use mid-range magnification as you move between Beta and Theta, then power up as you locate each one. The NGC 2207 and IC 2163 is an interesting double spiral galaxy complex for large scopes. While the results are far from a Hubble picture, it is possible with aperture to make out two brightened galactic cores whose outer regions overlap making it a most curious region to explore and well worth the hunt! The NGC 2223 is next along the line, and is also a spiral galaxy. There is a subtle hint of a core region, but for the most part this galaxy is evenly distributed with just the faintest indications of spiral structure at the outer edges. Continuing south will find the NGC 2217 – a somewhat brighter spiral galaxy that appears under higher magnification to have a halo surrounding it. Now for a jump back to Sirius (but don’t look at it!) and drop south below the binocular target – M41. The last of the galaxy hunt in Canis Major is tiny spiral, NGC 2280. Set in a delightfully rich field of stars, this shy oval of galactic “stuff” reveals only the faintest hint of an arm during excellent seeing conditions.

Wednesday, February 9 – Today is not only the 5th Anniversary of the STARDUST Launch, but Chinese “New Year” as well! Let’s celebrate it and dark skies by heading into more new studies.

The challenge to the Cetus field is not so much finding these objects as it is having the correct sky to see them. Heading to Diphda, we’re ready to drop down for galaxy study number one: the NGC 247. A very definite spiral galaxy with an intense “stellar” nucleus! Sitting right up in the eyepiece as a delightful oval, the NGC 247 is has a very proper galaxy structure with a defined core area and a concentration that slowly disperses toward its boundaries with one well-defined dark dust lane helping to enhance a spiral arm. Most entertaining! Continuing “down” we move on to the NGC 253. Talk about bright! Very few galactic studies come in this magnitude (small scopes will pick it up very well, but it requires large aperture to study structure.) Very elongated and hazy, it reminds me sharply of the “Andromeda Galaxy”. The center is very concentrated and the spiral arms wrap their way around it beautifully! Dust lanes and bright hints of concentration are most evident. and its most endearing feature is that it seems to be set within a mini “Trapezium” of stars. A very worthy study…

Now, let’s hop off to Delta, shall we? I want to rock your world – because the M77 rocked mine! Once again, easily achieved in the small scope, M77 comes “alive” with aperture. This one has an incredible nucleus and very pronounced spiral arms – three big, fat ones! Underscored by dark dust lanes, the arms swirl away from the center in a galactic display that takes your breath away! The “mottling” inside the structure is not just a hint in this ovalish galaxy. I guarantee you won’t find this one “ho hum”!

Thursday, February 10 – Today is the 30th Anniversary Mars 4, Mars Flyby. Hard to believe that only three decades later we’re still up there studying! By the way, today also marks Muslim New Year. Let’s celebrate with study!

With the very slim crescent of the Moon setting very early tonight, I ask you… Are you ready to dig deeper into Cetus? Then grab that map and let’s go! Delta will be our starting point here and the “fall line” runs west to east on the north side. First up is galaxy NGC 1073, a very pretty little spiral with a very “stretched” appearing nucleus that seems to be “ringed” by its arms! Continuing along the same trajectory, we find the NGC 1055. Oh, yes… Edge-on! This soft streak of light is accompanied by a trio of stars. The galaxy itself is cut through by a dark dust lane, but what appears so unusual is the core is to one side! Now we’ve made it to the incredible M77, but let’s keep on the path and pick up the NGC 1087 – a nice, even-looking spiral galaxy with a bright nucleus and one curved arm. Ready to head for the beautiful variable Mira? Then let her be the guidestar, because halfway between there and Delta is the NGC 936 – a soft spiral galaxy with a “saturn” shaped nucleus.

Ya’ done good, kid…

Friday, February 11 – Once again, the Moon will set early tonight. Wanna’ go play with the “Pup”?

The Puppis Star Fields are an exceptional challenge. Starting in the area of the binocular easy M46 and M47, a great place to hunt out is NGC 2423 – a soft collection of stars that resembles a fishook. Dropping south of the M47, we head on to tiny planetary nebula – NGC 2440 – who appears as nothing more than a slightly elongated “soft star”. Continue southwest for open cluster, NGC 2421 – a small open cluster that reminds me of an exquisitely tiny Brocchi’s Cluster! Ready for some more? Go for the M93 next, because a move southeast will find the NGC 2482 – a pretty, looping open cluster. Time to start nudging the scope to the southeast this time, to capture NGC 2467 a gentle open cluster also accompanied by a faint nebula. Continue on the same trajectory for open cluster, NGC 2453 – a small “patch” of faint stars.

Saturday, February 12 – And just when you thought I couldn’t go any lower, I ask you to wait until the crescent Moon has dipped below the horizon and Puppis stands high in the sky!

When Puppis stands straight up on the southern horizon, a clear sky provides a “peek” into those much sought after open clusters that can’t be found at any other time. Tonight we are going to move from east to west, dropping the field south on each successive pass. Starting southwest of Rho, we find the NGC 2489. Faint, but well resolved, this cluster is a double handful of diamond dust. Now, bump the field, and let’s rock again! Next pass brings up NGC 2489 – a rich field of stars, that seems to concentrate. Return again and let’s capture NGC 2533 – a very faint field of stars that are basically the same magnitude. A move over brings us to NGC 2439 – who is much brighter and also has a much larger star in the field. Get “down” now for the NGC 2571 – a “looping” field of faint stars with a couple of brighter members. A bit lower this time captures the NGC 2567 – a delightful group of stars that remind me of a greek letter.

Astronomy rocks!

Sunday, February 13 – Today is the birthday of J.L.E. Dreyer, a Danish-born Irish astronomer who came into the world in 1852. At the age of 22, Dreyer became the Assistant to Lord Rosse at Birr where the giant six-foot Leviathan – the world’s largest telescope – was at his disposal. It was here that he began a comprehensive survey of star clusters, nebulae and galaxies. His most important contribution to astronomy was The New General Catalogue of Nebulae and Clusters of Stars (NGC) published in 1888. This catalogue remains to this very day the standard reference used by astronomers the world over. He listed a fantastic total of 7840 objects! He followed with two supplementary Index Catalogues in 1895 and 1908 which contained an additional 5386 (IC) objects. It is the order in which they appear in these catalogues that define their names. It is also fascinating to note that most astronomers (including myself) still also use a form of “shorthand” devised by Dreyer, known as “Dreyer Descriptions” to make our own notations more brief and standard to all who read them some 117 years later after first being penned!

If a man who managed to view, describe and catalog 13,226 objects over his career says in a notation – !!! – you better go look!

Despite the Moon tonight, let’s do some comet hunting. Look for the Magnificent Machholz just a bit northwest of Gamma Camelopardalis. Still bright and still an easy binocular target! If you’d like more of a challenge, try spotting 9th magnitude C/2003 K4 less than half a moon’s width away from large, faint planetary – NGC 1360 – in Fornax. If you’d rather just relax with a bit of Moon? Metius, Fabricus and Jannsen will be your reward…

Until next week, keep Practicing, stay Patient and be Persistent! The sky is the limit… Keep reaching for the stars!

Light speed… ~Tammy Plotner

What’s Up This Week – Jan 31 – Feb 6, 2005

Image credit: Emmanuel Mallart
Monday, January 31 – So, where is Comet Machholz and what has it been doing while the Moon was out? Heading north! As we’ve watched its rapid progress (a degree a day at times!) since it first appeared in the south, you will now find Machholz tonight just southeast of Eta Cassiopeia. Having made its closest approach to the Sun and heading for the outer limits, C/2004 Q2 will soon start to shrink and fade, but it’s still a prime time player! Catch it tonight…

As we relaxed and viewed the “Great Orion Nebula” last week, I am sure that many of you realize this is a highly complex region of sky that deserves much more attention to detail. With the Moon satisfactorily out of the way during the early evening hours, let’s take the time to do a much more serious study over the next few evenings.

Tonight our goal is Iota Orionis. Known to the Arabs as “the Bright One of the Sword”, we know it as the southern-most star in its asterism’s namesake. Iota is estimated to be around 2000 light years away and is about 20,000 times brighter than our own Sol, but in the telescope you will find Iota to be an easy and charming triple star. The bluish B star is relatively close at 11″ in separation, but a bright 6.9 in magnitude. Much more distant at 50″ is the reddish C star, and far more disparate at magnitude 11. Iota itself is a spectroscopic binary and you will note another “white” double (Struve 747) unrelated to Iota about 8′ to the southwest.

Staying at high power, the reason I ask you to look here tonight is not to conquer a Herschel 400 object, but to study a region of the sky that would be far more impressive if it weren’t for its alluring neighbor. If you look closely, you will see that Iota is involved in a great region of emission nebula known as the NGC 1900 along with a small open cluster known as H 31. To be sure, the area is vague, as are all low surface brightness nebulae, but do look to the east of Iota where a much brighter, roundish area makes an unmistakable appearance!

Tuesday, February 1 – If you are up early this morning, today is the best time to catch lunar feature – Rupes Recta. The angle of the lighting will be just perfect to highlight this 110 km long feature!

Please take a moment to remember Columbia – the first Space Shuttle to travel to Earth orbit – and its brave crew who left us two years ago today. Rick D. Husband, William C. McCool, Michael P. Anderson, David M. Brown, Kalpana Chawla, Laurel Blair Salton Clark, and Ilan Ramon… We wish you godspeed.

Tonight let’s head for the “holy grail” of multiple star systems as we look into the fueling core of the M42 – Theta Orionis. Are you ready to walk into “the Trap”? Even the smallest of telescopes can reveal the four bright stars that comprise the quadrangle at the heart of the Great Orion Nebula known as the “Trapezium”. Both the beginner and the seasoned veteran know that there are actually eight stars in this region and the journey we are about to undertake requires both aperture and fine skies. But what can you really see?

All four primary stars are easy. A steady hand with binoculars and even the most modest of telescopes make this foursome an awesome sight… And they seem to be in a dark “notch” of their own, don’t they? A telescope of 150mm in aperture will reveal two additional 11th magnitude stars, but excellent skies could mean the even smaller aperture could detect them. They will appear as “red” companions to the “blue/white” primary stars. But what of the other two? The remaining two components average about magnitude 16, putting them within reach of large amateur scopes, but what would you see?

When I first began observing the Trapezium area with a 12.5″ telescope, I was sure that I would never see the two faintest members of the group. I was new to challenging double stars and had never looked at a diagram. (To this day, I still prefer to observe and describe things first and confirm them later. Knowing in advance what you are “supposed” to see colours what you “can” see.) I had seen the fainter stars that appeared as doubles, along with a faint wink here and there as well as one to the outside that made the whole thing appear like a pentagon. Little did I realize I was perceiving all eight members, and there seemed to be so much more just on the edge of my perception. Thus began my own personal quest to study the “Trapezium” on a more professional level, just like challenging galaxy studies.

Using the 31″ reflector at Warren Rupp Observatory, it was time to “walk into the Trap” and to answer all my observing questions through visual confirmation. While at first glance with a small telescope, the background region in this area might appear a black void – it is not. The nebula continues here, but changes form. Instead of seeing “smoke-like” filaments, the region around the Trapezium is scalloped, like fish scales. You can never see this in a photograph! I realized immediately that both the G and H stars that I had always questioned were quite within range of my 12.5″ as I recognized the pattern. Then a moment of perfect clarity came and the view literally exploded in dozens of stars buried within the field surrounding these eight known as the “Trapezium”.

Upon formal study, I found that there are around 300 such stars within 5′ of the Theta Orionis complex that exceed magnitude 17. According to Strand, the expansion rate puts them at an approximate age of 30,000 years, making it the youngest star cluster known. Regardless of what size telescope you use, you owe it to yourself to take the time to power up on the “Trap”. Since the time the area was revealed to my eyes in all its open glory, I have seen scallops in the nebula and both fainter members on nights with exceptional seeing in much smaller telescopes. No matter how many stars you are able to resolve out of this region, you are looking into the very beginnings of starbirth… A womb with a view!

Wednesday, February 2 – Do you get up for work before dawn? Take a moment to step outside and have a look at Jupiter. Our solar system’s largest planet will go stationary (retro) in its orbit during the early morning hours. You’ll find it within 3 degrees of Spica!

Tonight our study region is to the northeast of the Great Orion Nebula (M42) and has a designation of its own – M43. Discovered by De Mairan in the latter half of the 18th century, this emission nebula appears to be separate from the M42, but the division known as “the Fish Mouth” is actually caused by dark gas and dust within the nebula itself. At the heart of it is 7th magnitude “Bond’s Star” – and wouldn’t 007 be proud? This unusually bright OB star is creating a matter-bound Stromgren sphere!

Translated loosely, this star is actually ionizing the gas near it, making a orb shaped area of glowing hydrogen gas. Its size is governed by the density of both the gas and dust that surround “Bond’s Star”. This “exciting” star of our show is more properly known as Nu Orionis and near it lies a dense concentration of neutral material known as the “Orion Ridge”. It is this combination of dust – mixed with gases – that make for a well balanced area of star formation!

And besides… It’s just cool. 😉

Thursday, February 3 – This morning at 14:00 UT, the Moon will have reached maximum libration, turning Crater Otto Struve our way. And speaking of the Moon, on this day in 1966, the first soft landing on the lunar surface was achieved by Soviet Luna 9. Spaseba!

Lace up your Nikes and let’s head out tonight above The Great Orion Nebula and find “The Running Man”…

Located just a half a degree north of the M43, this tripartite nebula consists of three separate areas of emission and reflection nebulae that seem to be visually connected. The NGC 1977, NGC 1975 and NGC1973 would probably be pretty spectacular if they were a bit more distant from their grand neighbor! This whispery soft, conjoining nebula’s fueling source is multiple star 42 Orionis. To the eye, a lovely “triangle” of bright nebula with several enshrouded stars make a wonderfully large region for exploration. Can you see the “Running Man” within?

Friday, February 4 – Wake up, Europe! This morning the crescent Moon will occult Antares for a substantial portion of viewers. Please check IOTA tables for viewing areas and times. Klare nacht!

For those of us not so fortunate, we can always look about 8 degrees north of Mars this morning for Pluto as we note its discoverer – Clyde Tombaugh – born on this day in 1906.

Let’s return again to Orion tonight, but preferably with binoculars since we will be studying a very large region known as “Barnard’s Loop”. Extending in a massive area about the size of the “bow”, you will find Barnard’s photographic namesake to the eastern edge of Orion, where it extends almost half the size of the constellation between Alpha and Kappa.

Because the Orion complex contains so many rapidly evolving stars, it stands to reason that a supernova should have occurred at some time. “Barnard’s Loop” is quite probably the shell leftover from such a cataclysmic event. If taken as a “whole”, it would encompass 10 degrees of sky!

For the most past, the nebula itself is very vague, but the eastern arc (where we are observing tonight) is relatively well defined against the starry field. Although it is similar to the Cygus Loop (“Veil Nebula”), our Barnard Loop is far more ancient. If you have transparent, dark skies? Enjoy! You can trace several degrees of this ancient remnant using just binoculars.

Saturday, February 5 – On this day in 1963, the first quasar redshift was measured by Maarten Schmidt and in 1974 Mariner 10 captured the first close-up photos of Venus.

Tonight I ask you to once again take out your telescopes and explore a region with me that we have previously visited – the M78. It is for the very sake of amateur astronomy that I ask you to do this… And here is why!

On January 23, 2004 a young backyard astronomer named Jay McNeil was checking out his new 3″ telescope by taking some long exposures of the M78. Little did Jay know at the time, but he was about to make a huge discovery! When he later developed his photographs, there was a nebulous patch there that had no designation. When he reported his findings to the professionals, they confirmed it had no official designation and that Jay had stumbled onto something quite unique! It is believed that Jay’s discovery was a variable accretion disc around newborn star – IRAS 05436-0007. Little is known about the region, but it seems that it had been caught in a photo once in the past but never studied. Even the Digital Sky Surveys had no record of it!

Although Jay’s discovery might not be bright enough tonight to be seen just south of the M78, it is a variable and circumstance plays a big role in any observation. Before you think that being a backyard astronomer has no real importance to science — remember a teenager in a Kentucky backyard with a 3″ telescope…

Catching what professionals had missed!

Sunday, February 6 – Do you need a smile? Then look at the waning crescent Moon this morning. On this day in 1971, Apollo 14 astronaut Alan Shepherd was the first human to “tee off” from the lunar surface! I wonder if that golf ball is still orbiting?!

Tonight let’s return again to Orion’s “Belt” and bright eastern star Zeta. Having visited this before, we know Alnitak is a delightful triple as well as home to the incredible “Flame” and “Horsehead” nebula. Heading next to the western-most of the trio, we find Delta – or Mintaka. Even small telescopes will be delighted to find that Mintaka is also a double with its 6.7 magnitude “blue” companion at an easy separation of 53″ north of the primary.

But you knew I was saving the best for last, didn’t you?

Now let’s go for the center-most star and identify Epsilon. Known to the Arabs as Alnilam, or the “Belt of Pearls”, Epsilon is a super-giant star that resides about 1600 light years away from us. For those with average telescopes, you will notice a “haze” around Alnilam and you would be correct. It is also surrounded by a reflection nebula
NGC1990 – a circular gaseous region that spans around 20 light years, fueled by Epsilon’s bluish light. The NGC1990 is surrounded by “Herbig-Haro” or “HH” bi-polar jets. It is rumored that an 8″ or 10″ telescope at 250x will reveal these globules as 14th magnitude “fuzzy stars”. What do you see?

Until next week? Keep exploring the fantastic Orion region. There are many planetary nebulae and open star clusters (even a galaxy or two) waiting for you! Do not be discouraged if you cannot see some of these things on your first try – astronomy is like anything else – it takes Practice! If you don’t have skies tonight? Have Patience. And if you are still learning what type of conditions it takes to see things at their best? Be Persistent! Practice + Patience + Persistence = Perfection!

Light speed…. ~Tammy Plotner

What’s Up This Week – Jan 24 – Jan 30, 2005

Monday, January 24 – Up early? Great! Then let’s start the week off on authoritative note as Mars will be officially declared to have reached magnitude 1. As we’ve watched its return, the gain in brightness has us ready to once again begin viewing and looking forward to opposition at the beginning of November.

The Moon will dominate the evening skies tonight, but there are myriad delights to be explored on the lunar surface despite its brightness. It’s a fantastic opportunity to discover the bright rays of Tycho and explore “splashy” areas like Copernicus, Aristarchus and Keplar. How far can you trace the rays? Can you see the long ray that cuts across Mare Serentatis? Notice the crater rim of Plato to the north, how does it compare to Grimaldi in the west? For those with filters, enjoy looking for the bright rings of craters Dionysius and Pytheas. No filter? No problem! Although this might sound a bit strange, try wearing a pair of polarized sunglasses while viewing – you’d be surprised!

Only five degrees south of our “phat” Moon tonight, you will find the “Lord of the Rings” – Saturn. With the whole world buzzing about the excitement of the successful Huygens landing, why not invite family or friends to view with you? Titan is easily visible in even small scopes and it’s a wonderful opportunity to spark a child’s imagination!

Tuesday, January 25 – The Moon reaches Full this morning at 5:32 a.m. EST. Tonight it will rise within minutes of sunset and its majestic form at this time of year has long been captured in folklore. Known by many names, such as the Cold Moon, Winter Moon, Quiet Moon or Snow Moon, it is certainly an inspiring sight against the backdrop of the diamond bright stars of winter. Tonight let us visit the most brilliant star of all – Sirius.

Also known as the “Scorching One”, Alpha Canis Majoris is the brightest of the fixed stars at an amazing -1.42. With the exception of Alpha Centauri, Sirius is the closest of all the stars that we can see unaided at only 8.7 light years away – but it’s not standing still. As part of the Ursa Major Stream of moving stars, it has changed its position by one and half times the apparent width of the Moon in just 2000 years!

In the telescope, this main sequence star is a dazzling white tinged with blue. But thanks to our atmosphere, Sirius’ light will produce all the colors of the rainbow as it sparkles in our eyes. For many of us this beautiful iridescence is all we will ever see of Sirius, but for those with 10″ and larger telescopes a perfectly steady sky will reveal Alpha Canis Majoris’ secret – a white dwarf companion! Although this 8.5 magnitude star is well within the range of even small scopes, the blinding glare of the primary makes it a very elusive target. In another 20 years it will have reached its maximum separation of 11.5″, but keep a watch to the southeast as you view the “Scorching One” tonight – perhaps you’ll spot Sirius B!

Wednesday, January 26 – With just a small margin of time tonight to explore before the Moon rises, why not try your hand at a less popular Messier object? The M79 is located in the southern constellation of Lepus and it’s quite easy to find! Beta and Epsilon are the two southernmost stars, below them and forming a shallow “triangle” is a slightly dimmer star. Holding your hand at arms length, the M79 is two finger-widths away to the northeast.

Originally discovered by Mechain in October of 1780, Charles himself didn’t get around to looking at one of the very few globular clusters of winter until December of that year. On a good night, this small “round fuzzy” can be spotted with binoculars, but truly takes a telescope to appreciate. Moving away from us at 188 miles per second, the 8th magnitude M79 will show as a concentrated ball of unresolvable stars to small aperture and begin resolution with larger scopes. At around 42 light years away, this often over-looked Messier object is one of the very few globular cluster that resides further out in Milky Way galaxy than our own solar system!

If you need a winter smile, then wait about 3 hours after sunset tonight to check out the constellation of Leo – the “Lion” is taking a bite out of the Moon! Note the faint crown of stars about a hand span to the upper left of Luna. This is the “head” – while bright Regulus to the lower left is the “heart”. The figure becomes complete as the triangle of stars to the east represents the great “Lion’s” haunches.

Thursday, January 27 – Although the Moon will rise quite early tonight, open clusters make a fine target, so let’s head out toward Gemini and discover yet another Messier object that contains “more than meets the eye” – M35!

Cataloged by Messier in 1764, the M35 is easily found by locating Eta Geminorium and moving just slightly more than two finger-widths to the northwest. Best appreciated at lowest power, this very “open” cluster contains many different spectral types and magnitudes that are visible even in binoculars. At around 2200 light years away, large aperture telescopes at minimal magnification will pick up on an additional bonus on the cluster’s southwest edge. The NGC 2158 is about six times more distant than the M35. This very concentrated galactic cluster is roughly 8 million years old, making the trip to the M35 a dual delight!

If you’d like proof that the “Lion” had the Moon in its mouth yesterday, have look at the lunar surface tonight with a telescope or binoculars. Just north of the terminator’s mid-point you will see the very last remnants of the west wall of Mare Crisium – looking very much like a “bite” taken out of the lunar edge!

Friday, January 28 – And speaking of lunar geography, today Johannes Hevelius was born in 1611. So what, you say? Then think on this… Hevelius was using a telescope to view the Moon’s surface and produced the very first detailed maps which were published as “Selenographia” in 1647. That’s 358 years ago! The Polish astronomer then went on to name a constellation that still remains in use today – Lynx. When asked to explain how he came up with the name, he said that an observer needed to have eyes like a lynx just to see it!

Tonight let us celebrate Hevelius’ achievements by putting on our “cat’s eyes” as we go in search of one of the most distant objects in our galaxy – the NGC 2419. As a telescopic object only, this magnitude 11.5 study requires clear dark skies and at least 150mm of aperture. Since Lynx is a difficult constellation, you will find this easier by going 7 degrees north of Castor. You will know if you have the correct field if two stars appear to the western edge of a hazy patch. There is a very good reason “why” this elusive globular cluster is so special!

Most commonly known as “the Intergalactic Wanderer”, the NGC 2419 is so distant that it was at one time believed to actually be outside our own galaxy. Almost all globular clusters are found within our galactic “halo” – a region which exists about 65,000 light years around the galactic center. Our faint friend here is at least 210,000 light years from where it should be! When I tell you it’s out there… I’m not kidding. The NGC 2419 is as distant as our galactic “neighbors”, the Magellanic Clouds! But don’t worry, our galaxy has sufficient gravitation to keep “the Intergalactic Wanderer” around long enough for you to capture it for yourself!

Saturday, January 29 – While the Moon is absent from our early evening sky, take the time to simply go out and look up! The Winter Milky Way is a very glorious sight, with the Perseus and Orion spiral arms stretched overhead from the northwest to southeast. How could you not want to explore?! Tonight let’s aim binoculars and telescopes at one of the finest areas in our galaxy – the “Great Orion Nebula”.

One could devote years to studying just this region of the sky, as I could devote thousands upon thousands of words to tell you of its structure and beauty. Around 1600 light years away from us, this huge glowing cloud of “star stuff” is mainly florescence fueled by the extreme temperatures and ultra-violet radiation coming from its heart – Theta Orionis. Even small binoculars can see this “furnace” of four stars, but we will explore their intricacies at a later time. Tonight I would rather you just relax and note all delicate structure embedded in this grand nebula. For telescopes to truly grasp the vastness of this region, turn off your drives and allow it to flow gently past your gaze as you watch filaments, ribbons and encased stars sail past. For large telescopes, there is no more glorious sight than the fine streamers and slender threads which extend well beyond the bright parameters. There are loops, curls and swirls to be examined and the more aperture you have – the grander it becomes. If you sense this is an area of great turbulence, like frozen smoke, you would be correct. There are widely varied radial velocities throughout the structure!

Just relax and enjoy… It’s the finest in the night sky.

Sunday, January 30 – In the very early morning hours, the Moon will occult bright star Eta Viriginis for the biggest majority of Canada and the United States. See IOTA for times and locations. (I caution you this is right on the dividing line of time and date, so please make suitable adjustments for your specific locale.)

With a considerable amount of time before the Moon rises tonight, let’s bundle up in parkas and snow boots as we head for a namesake planetary nebula so fitting for this time of year – “The Eskimo”!

Fairly easily found by locating Wasat – Delta Geminorum – at the “waist” of Gemini, use the finderscope to locate wide double, 63 Geminorum to the east. You will find the NGC 2392 is only 2/3 of a degree southeast. Easily distinguished in even small telescopes as a blue/green “disc”, this colorful planetary nebula is around 3000 light years from us and requires large aperture to truly appreciate. At high power the 10th magnitude central star is very apparent and some of the “features” seen in photographs can be caught. While our eyes can never resolve the “Eskimo” in the same fashion that CCD imaging can, it is still possible to see the faint halo that surrounds the inner nebulosity, appearing much as a “parka-like hood” around a human face. Who knows? If we stay out in the cold long enough, we might even see “polar” bears rising in the northeast! Welcome back, Ursa Major…

And if you are out late enough to see the Moon rise in the northern hemisphere, have a look for Jupiter about 2 degrees to Luna’s lower left. If you were to watch all night, you would see the Moon cruise along just below the “Mighty Jove’s” position. By the time that dawn begins to stain the eastern sky, you will see the two ecliptic “dance partners” have now switched positions as the Moon is now 2 degrees to the lower left of Jupiter!

Until next week? Stay warm while you’re observing. We might be looking at the Moon, but we’re still reaching for those far away stars! Light speed… ~Tammy Plotner

What’s Up This Week – Jan 17 – Jan 23, 2005

Monday, January 17 – Before dawn this morning, try having a look for Mars and red Antares on the rise. The first precise observation of Mars’ position dates back to this day in 272 BC, but was observed by Aristotle as early as 356 BC. So what’s the significance of looking? Translated, Alpha Scorpi – or Antares – means “rival of Mars”. Did you know Mars was originally named Ares? So “Antares” quite literally means “not Mars”. As you look for our ruddy points of light this morning, take hope. Antares will rise four minutes earlier tomorrow morning, and every day afterwards. Being able to sight a “summer star” can only mean winter for the Northern Hemisphere is getting shorter by 240 seconds every day!

While you are out, be sure to keep a watch for the Coma Berenicids meteors. This widely varied stream is still producing around one to two meteors per hour, and they are among the fastest meteors known – reaching speeds of up to 65 kilometers per second!

And since we’re “early to rise”, let’s head for an “early to bed” as we celebrate American scientist, Benjamin Franklin’s 299th birthday with an early evening observation of the seven-day old, first quarter Moon. Tonight’s outstanding feature will be the Alpine Valley. Located tonight near the terminator in the northern lunar hemisphere, this wonderful “gash” very conspicuously cuts across the lunar Alps just west of crater Aristotle. As you view this 180 km long and (at points) less than 1 km wide feature, ask yourself how it was formed. Perhaps an asteroid once sliced its way through the forming region? Even science doesn’t have a perfect answer for this one!

Tuesday, January 18 – Let’s return again to the Moon tonight to explore. The most prominent feature distinguishable in binoculars and small telescopes will be the rather blank looking oval of crater Plato, but the feature we’re really interested in is just south – Mons Pico. Appearing as an almost “star-like” point of light to binoculars, telescopes will enjoy this singular mountain for the long shadow it casts on the barren lunar landscape. No doubt comprised of white rock that has high reflecting power, Mons Pico will appear to look almost like a pyramid alone on the grey sands on Mare Ibrium. With an estimated height of 2400 m, this particular lunar feature will be lost over the next few nights. How long can you follow it?

One hundred years ago today, the United States bought their first airplane from the Wright Brothers – perhaps tonight we’ve found it?

Wednesday, January 19 – Head’s up for the United States and Southern Canada. Tonight the Moon will occult 4.4 magnitude Delta Aries! Timing for these type of events is very important so please visit this IOTA page for precise times and locations. If you have never watched a lunar occultation, I highly recommend it. Even binoculars can reveal the event and there is something very exciting about witnessing a star wink out!

Scottish engineer, James Watt was born on this day in 1736. We know my famous forefather held the patent for improvements on the steam engine, but did you know that James Watt was the first to use a telescope in surveying? Tonight let’s celebrate the date of his birth by surveying one of the most impressive features on the Moon – Clavius. As a huge mountain-walled plain, Clavius will appear near the terminator tonight in the lunar southern hemisphere, rivaled only in sheer size by similar structured Deslandres and Baily. Rising 1646 meters above the surface, the interior slopes gently downward for a distance of almost 24 km and span 225 km. Its crater-strewn walls are over 56 km thick! Clavius is punctuated by many pockmarks and craters, the largest on the southeast wall is named Rutherford. Its twin, Porter, lay to the northeast. Long noted as a “test of optics”, Clavius crater can offer up to thirteen such small craters on a steady night at high power. How many can you see? (If you think that’s tough, see if you can spot the Pleiades only two degrees away unaided!)

Thursday, January 20 – We would like to wish Buzz Aldrin a very happy 75th birthday! For those of us who enjoy studying the lunar surface, we can never look without hearing Aldrin’s description of “Magnificent desolation.” It is this kind of bravery and dedication to exploration that inspired us all! So let’s look tonight…

The ten-day old Moon will offer many features such as the fully disclosed Tycho, the incomparable Copernicus and the fascinating Bulliadus, but tonight we’ll be looking for an asterism – “The Great Wall”. By drawing a mental line from Tycho to Copernicus, extend that line by two-thirds the distance north. It is here that you will discover what looks like huge wall on the lunar surface – and at some 48 km high and 161 km long, that would be a great wall! In fact, it is nothing more than the western portion or the Juras Mountains which surround the lovely Sinus Iridum – but it’s definitely a rather striking feature and well worth the time to look in both binoculars and telescopes. Klare nacht!

Also born on this day in 1573 was Simon Mayr. He also observed the moons of Jupiter at nearly the same time as Galileo. Although Jupiter’s many satellites are known as “galilean moons”, it was Mayr who assigned them the Greek names we still use today. For many of us, Jupiter rises far too late for observation, and is often clouded out in the mornings – but did you know that you can listen to Jupiter as well? Visit with my friends at Radio JOVE for both real-time audio as well as information on how to acquire a Radio JOVE receiver of your own! Enjoy…

Friday, January 21 – How about if we try to ignore the Moon tonight and instead search for Comet C/2004 Q2? Unaided-eye detection will be next to impossible, but we’re in luck as the “Magnificent Machholz” will be only three degrees above Alpha Persei. Making its closest approach to the Sun in just a few days, spotting Comet Machholz’ dust tail with so much moonlight will be a real challenge – but at my last observation the ion tail was so strong it just might show! Having passed closest to the Earth earlier this month, Comet Machholz is delighting viewers with clear skies world-wide. On its way to becoming a circumpolar object, this great comet will make a wonderful sight in binoculars with 1.8 magnitude Mirfak in the same field. If you plan on using a telescope, be sure to take the time to study this giant star as well! As the senior member of the Alpha Persei group, this particular star is around 4000 times more luminous than our own Sun and is about 570 light years away. If you are able to discern the other bright stellar members of this group, make note of their position! They might not be cruising quite so fast as Comet Machholz, but they will have changed positions in the sky by around one degree in say… 90,000 years? Just a cosmic sneeze!

On this day in 1792 , John Couch Adams, the man who predicted the existence of Neptune. was born and he shares the same birthday as Bengt Stromgren, who came into the world in 1908. Stromgren was the developer of the theory of ionization nebulae. Why not recognize his achievements by visiting an H II region tonight that not even the Moon can outdo! Let’s head for the “Great Orion Nebula”… Although a lot of the subtle detail will be lost in the moonlight, to think that we can see such a rare “light” from 1900 light years away is pretty amazing! (And we’ll definitely be back to study.)

Saturday, January 22 – This time of year is best to look for some strange occurrences that are not astronomy-related – but wonderful for SkyWatchers! Thanks to a multitude of high thin clouds and an abundance of ice crystals in our atmosphere, be on the lookout for various forms of atmospheric phenomena. The most common is known as the “sun dog” and will look very much like a mock rainbow that appears in a small portion of the sky near the Sun. Much more dramatic is the “sun pillar”, which will look like a huge column of light towering over the Sun both during rise and set. A lot less common, but certainly inspiring is the “parhelic arc”, which appears as a circular (in whole or part) “rainbow” directly around the Sun. Do these things only happen during the day? No! It is not uncommon on frigid nights to see “light pillars” above distant street lights, or to catch a “moon dog” when conditions are just right. For more information on these fantastic phenomena, as well as some downright awesome photos, please take the time to visit with Atmospheric Optics. It makes the cold months just a little more warm…

If you have a new telescope you’d like to try out and want a lunar feature that’s a bit less obvious, then tonight let’s try for crater contrasts. The Oceanus Procellarum is the vast, grey “sea” that encompasses most of the northwestern portion of the Moon. On the terminator to its southwest edge, (and almost due west geographically) you will see two craters of near identical size and depth, but not identical lighting. The southernmost is Billy – one of the darkest floored areas on the Moon. It will appear to have a bright ring (the crater rim) around it, but the interior is as featureless as a mare! To the north is Hansteen – note how much brighter and more detailed it is. It’s easy to discern that Billy once filled with smooth lava flow, while counterpart Hansteen evolved much differently!

Sunday, January 23 – Tonight the Moon will be at its furthest point from the Earth (apogee), but not far enough to darken skies as its gibbous form appears almost two hours before sunset and reveals Saturn only six degrees away at skydark. Almost an equal distance on the other side of our “near full” Moon are the famous “twins” of Gemini – Castor and Pollux. Aim your telescopes at the northernmost of these stars as we briefly explore Alpha Geminorum!

What we are looking at when we view Castor is six-part star system that is around 45 light years away. In a telescope, only three of these stars are visible. If you look carefully, you will see the primary star is actually a fairly close double, only separated in brightness by about 1 magnitude. Each of these two stars is also a spectroscopic double and their companions orbit within just a few million miles of their primary star in a matter of days. To really understand just how close this system is, imagine our own Sun being twice its size and having a small companion orbiting even closer than Mercury. Somewhere out around Pluto would be an identical sun and companion! Moving elliptically around each other, our pair of doubles takes about 400 years to orbit each other. At closest, we would see a separation of about 1.8 arc seconds, but right now they are about 2.2 arc seconds apart and the gap is gradually widening. In around 50 years from now, this “pair of pairs” will have moved to almost 6.5 arc seconds apart!

If you want an additional challenge, see if you can spot the 9.5 magnitude “orange” C star widely placed southeast of our tight system. It is also a spectroscopic binary that belongs to the same “group”. It’s about two-thirds the size of our own Sun and its identical companion orbits in 24 hours at only about a million and a half miles away. But don’t expect to see them change soon, for it takes this particular pair 10,000 years to orbit 100 AU away the dual primary stars. Perhaps we could find a few “sunny” days there?

And that’s it for now. I sure hope that some of you have had clearer skies than I have! Until next week? Ask for the Moon – but keep reaching for the stars! Wishing you clear skies and light speed… ~Tammy Plotner

What’s Up This Week – Jan 3 – Jan 9, 2005

Monday, January 3 – For those of you who were brave enough to fight the cold this morning to look for the annual Quandrantid meteor shower? Bravo! But if bad skies or arctic temperatures kept you from viewing, you still have another opportunity because this unusual meteor shower peaks over a period of two days.

The Quadrantid meteor shower has been known to be an incredibly concentrated display – at times producing between 50 to 120 meteors in the northern hemisphere. It is infrequently observed simply because of low temperatures in the north and bad positioning in the south. Another reason we do not known much about this shower is the short period of time that it is active. The peak can only last a few hours! The meteoroid stream itself is vast, but very accurate predictions are difficult thanks to complex streams perturbed by Jupiter’s gravity. The precise source of the Quadrantid meteor wasn’t even discovered until December 2003! Just slightly over a year ago, Peter Jenniskens of NASA Ames Research Center found evidence that tied the Quadrantids to an extinct comet now known as asteroid 2003 EH1. Historical observations reveal this comet was visible some 500 years ago, but may have suffered some type of impact that caused it to break up. Because we hit this “debris stream” at a perpendicular angle, we are “in and out” rather quickly – making precise calculations difficult at best.

The Quadrantids are named for a constellation that no longer exists on modern star atlases – Quadrans Muralis. In 1922, the International Astronomical Society removed it (along with several others) from the overburdened sky maps leaving only 88 officially designated constellations. So where do you look? The accepted radiant for the Quadrantids has now been assigned to Bootes, but the stream kept its original name to help distinguish it from another annual January shower – the Bootids. Even though the constellation might be gone, your chances are still good of catching one of these “frosty meteors”! The hours after local midnight will be best as we move into January 4. Although the waning Moon will decrease the number you may see, be sure to watch for “colors” in the display. As meteors burn up in our atmosphere, they produce colors thanks to their chemical spectra and the Quadrantids are known to range from blue to green. Best of luck!

Tuesday, January 4 – Heads up for Africa and southwestern Australia! It’s your turn for an astronomical event as the Moon will occult Jupiter for your location in the early morning hours. (see? i haven’t forgotten you!) Timing is absolutely critical for this type of observation, so please visit this IOTA page for the precise path and list of times for your area. For those of us who will only see the Moon and Jupiter separated by less than 7 degrees, we wish you clear skies!

For sky watchers around 40 degrees north, this morning will mark the latest sunrise of the year. Why not take advantage this morning before beginning your busy day and have a look at the simple beauty of the ecliptic plane? To the east and down low on the horizon will be Mercury and Venus, above them (about 17 degrees to the west) will be tiny Mars. Almost overhead, and just slightly south will be Jupiter and west of it will be the Moon. Continue your visual journey to the far west as Saturn completes this lovely arc.

With plenty of time to spare before the Moon rises tonight, let’s try for a new Messier object. Located slightly more than 2 degrees northeast of Zeta Orionis and right on the celestial equator is a delightful area of bright nebula known as the M78 (NGC 2068). Often over-looked in favour of “the Great Orion Nebula”, this 8th magnitude diffuse area is easily captured with small scopes. Discovered by Mechain in 1789, the M78 is part of the vast complex of nebulae and star birth that comprise the Orion region. Fueled by twin magnitude 10 stars, the nebula almost appears to the eye to resemble a “double comet”. Upon close scrutiny, observers will note two lobes separated by a dark band of dust and each lobe bears its own designation – NGC 2067 to the north and NGC 2064 to the south. While studying, you will notice the entire area is surrounded by a region of absorption, making the borders appear almost starless! The M78 itself is filled with T Tauri type stars… But we’ll explore why these variables are incredible as we examine their prototype later this week.

Wednesday, January 5 – Tonight let’s take a journey just a breath above Zeta Tauri and spend some time with the most famous supernova remnant of all – the M1. Factually, we know the “Crab Nebula” to be the remains of an exploded star recorded by the Chinese in 1054. We know it to be a rapid expanding cloud of gas moving outward at a rate of 1,000 km per second, just as we understand there is a pulsar in the center. We also know it as first recorded by John Bevis in 1758, and then later cataloged as the beginning Messier object – penned by Charles himself some 27 years later to avoid confusion while searching for comets. We see it revealed beautifully in timed exposure photographs, its glory captured forever through the eye of the camera — but have you ever really taken the time to truly study the M1? Then you just may surprise yourself…

In a small telescope, the “Crab Nebula” might seem to be a disappointment – but do not just glance at it and move on. There is a very strange quality to the light which reaches your eye, even though at first it may just appear as a vague, misty patch. To small aperture and well-adjusted eyes, the M1 will appear to have “living” qualities – a sense of movement in something that should be motionless. This aroused my curiosity to study and by using a 12.5″ scope, the reasons become very clear to me as the full dimensions of the M1 “came to light”.

The “Crab” Nebula holds true to so many other spectroscopic studies I have enjoyed over the years. The concept of differing light waves crossing over one another and canceling each other out – with each trough and crest revealing differing details to the eye – is never more apparent than during study. To truly watch the M1 is to at one moment see a “cloud” of nebulosity, the next a broad ribbon or filament, and at another a dark patch. When skies are perfectly stable you may see an embedded star, and it is possible to see six such stars. It is sometimes difficult to “see” what others understand through experience, but it can be explained. It is more than just the pulsar at its center teasing the eye, it is the “living” quality of which I speak -TRUE astronomy in action. There is so much information being fed into the brain by the eye!

I believe we are all born with the ability to see spectral qualities, but they just go undeveloped. From ionization to polarization – our eye and brain are capable of seeing to the edge of infra-red and ultra-violet. How about magnetism? We can interpret magnetism visually – one only has to view the “Wilson Effect” in solar studies to understand. What of the spinning neutron star at its heart? We’ve known since 1969 the M1 produces a “visual” pulsar effect! We are now aware that about once every five minutes, changes occuring in the neutron star’s pulsation effect the amount of polarization, causing the light waves to sweep around like a giant “cosmic lighthouse” and flash across our eyes. For now, l’ll get down of my “physics” soapbox and just let it suffice to say that the M1 is much, much more than just another Messier. Capture it tonight!!

Thursday, January 6 – Since we’ve studied the “death” of a star, why not take the time tonight to discover the “birth” of one? Our journey will start by identifying Aldeberan (Alpha Tauri) and moving northwest to bright Epsilon. Hop 1.8 degrees west and slightly to the north for an incredibly unusual variable star – T Tauri.

Discovered by J.R. Hind in October 1852, T Tauri and its accompanying nebula, NGC 1555 set the stage for discovery with a pre-main sequence variable star. Hind reported the nebula, but also noted that no catalog listed such an object in that position. His observance also included a 10th magnitude uncharted star and he surmised that the star in question was a variable. On either account, Hind was right and both were followed by astronomers for several years until they began to fade in 1861. By 1868, neither could be seen and it wasn’t until 1890 that the pair was re-discovered by E.E. Barnard and S.W. Burnham. Five years later? They vanished again.

T Tauri is the prototype of this particular class of variable stars and is itself totally unpredictable. In a period as short as a few weeks, it might move from magnitude 9 to 13 and other times remain constant for months on end. It is about average to our own Sun in temperature and mass – and its spectral signature is very similar to Sol’s chromosphere – but the resemblance ends there. T Tauri is a star in the initial stages of birth!

So what exactly are T Tauri stars? They may be very similar in ways to our own Sun but they are far more luminous and rotate much faster. For the most part, they are located near molecular clouds and produce massive outflows of this material in accretion as evidenced by the variable nebula, NGC 1555. Like Sol, they produce X-ray emissions, but a thousand times more strong! We know they are young because of the spectra – high in lithium – which is not present at low core temperatures. T Tauri has not reached the point yet where proton to proton fusion is possible! Perhaps in a few million years T Tauri will ignite in nuclear fusion and the accretion disk become a solar system. And just think! We’re lucky enough to see them both…

Friday, January 7 – For mid-northern latitudes, this morning will be the last chance to see the crescent Moon (gosh, aren’t you crushed?) before it goes new. But for those living in northwestern America, the treat will be extra special as the Moon will occult Antares! Be sure to visit IOTA for precise times and locations.

Are your ready for a real weekend treat? Then look no further than the night sky above as Comet Machholz will be putting on one of the best shows of the year as it appears around 2 degrees west of the Plieades star cluster!

Near the ecliptic, and with a rough visual magnitude of slightly less than 2, the Plieades (M45) will appear brighter than Comet Machholz – but current information suggests that C/2004 Q2 will have achieved 4th magnitude by that time – making both easy unaided-eye objects. Average binoculars span a field of around 4 degrees, so both objects should fill the field of view! While watching, take the time to practice with size, distance and magnitude observations. The M45 spans approximately 1.2 degrees of sky – how does the size of the comet’s coma compare? Since the two are around 2 degrees apart, how long does the tail seem to span? The brightest of the major stars in the Plieades is 2.8 and the dimmest approximately 5.6 – by defocusing, how bright does Comet Machholz nucleus appear in comparison? You know what direction the M45 is from Machholz, which way does the twin tail appear to go?

Of course, you needn’t truly worry about any of this just to enjoy the view! I’ll race you there…

Saturday, January 8 – So are you ready for a real challenge? Then take advantage of dark sky time to head toward Orion. Tonight our aim is toward a single star – but there is much more hiding there than just a point of light!

Our goal is the eastern-most star in the “belt”, Zeta Orionis, or better known as Alnitak. At a distance of some 1600 light years away, this 1.7 magnitude beauty contains many surprises – the first being that Zeta is a triple system. Fine optics, high power and steady skies will be needed to reveal this challenge! Want more? Then look about 15′ east and you will see that Alnitak resides in a fantastic field of nebulosity which is illuminated by our tripartite star. The NGC2024 is an outstanding area of emission that holds a rough magnitude of 8 – viewable in small scopes but will require dark sky. So what’s so exciting about a fuzzy patch? Then look again, for this beauty is known as the “Flame”! Larger telescopes will deeply appreciate this nebula’s many dark lanes, bright filaments and unique shape! Still not enough? Then break out the big scopes and put Zeta out of the field of view to the north at high power and allow your eyes to re-adjust. When you look again, you will see a long, faded ribbon of nebulosity called IC434 to the south of Zeta that stretches for over a degree. The eastern edge of the “ribbon” is very bright and mists away to the west… But hold your breath and look almost directly in the center. See that dark notch with two faint stars south of it? You have now located one of the most famous of the Barnard dark nebula – B33.

You may exhale now. The B33 is also known as the “Horsehead Nebula”. The “Horsehead” is a very tough visual object – the classic chess piece shape only seen in photographs – but those of you who have large aperture can see a dark “node” that is improved with a filter. The B33 itself is nothing more than a small area comsically (about 1 light year in expanse) of obscuring dark dust, non-luminous gases, and dark matter – but what an incredible shape! If you do not succeed at first attempt? Do not give up. The “Horsehead” is one of the most challenging objects in the sky and has been observed with apertures as small as 150mm. Keep trying! This just might be your lucky “Knight”…

Sunday, January 9 – Tonight’s destination will be within our own solar system, but with good reason! As we know, all the orbits of the planets are tilted relative to our own Earth’s orbit. This means that each time a planet completes an orbit around the Sun, it must pass over our own orbital plane twice. One time it will move from above Earth’s orbit to below, and the next it will go in the opposite direction. Tonight, Saturn will cross Earth’s orbital plane from below to above and this action of passing is what is astronomically known as the “ascending node”. It is rather special because it will be another 29 years before Saturn completely orbits the Sun and achieves the “ascending node” again!

So what does that mean to those wishing to view Saturn tonight? Not much other than it is a “cool” astronomy fact. The best time to view Saturn is at opposition which won’t occur for about another year. The most interesting part about watching Saturn right now is the ring system. Like our Earth, Saturn tilts on its axis. Since the ring system is equatorial, our best views of the rings themselves come when Saturn is highly inclined. As luck would have it, Saturn is well placed right now for just such viewing. Right now, it’s saturnian winter for the Ring King’s northern hemisphere, so get thee out there an explore! Small telescopes at high power can make out the pencil slim line of the Cassini Division on a stable night, while larger telescopes can easily spot other ring divisions. Be sure to watch for Saturn’s many moons as well. Titan is easily visible to the smallest of scopes and even a 114mm can reveal as many as four others. Enjoy it tonight!

Is it gone yet? Yes! New Moon week is about to begin, so expect some more challenging objects for veteran observers next time. For those just beginning? Don’t worry. There will be plenty for you to explore as well! I would like to thank all of you who take time to write – you’ll never know how much I appreciate it! (and earthlink users? please check your rejected mail for answers to your questions.) Until next time, ask for the Moon but keep reaching for the stars!

Light speed… ~Tammy Plotner

What’s Up This Week – Dec 20 – Dec 26, 2004

Image credit: NOAO
Season’s Greetings, fellow SkyWatchers! Take the time from your busy holiday schedule to relax with some astronomy. There will be three minor meteor showers this week: the Coma Berenicids, Delta Arietid and the Ursids. The waxing Moon will become our guide as we locate historic variable Mira. Mare Humorum and Crater Gassendi are great features to learn about on the lunar surface and we’ll travel to the outer arm of our own galaxy to study a multiple star system – Sigma Orionis. Not enough? Then I have a special and very challenging surprise for you on Christmas Day! Although the Moon goes full during this seven-day period, those who are just beginning with new telescopes will appreciate its presence as an easy “pointer” to Saturn. So lift your eyes toward the heavens and enjoy the bright stars of Winter…

Because here’s what’s up!

Monday, December 20 – If you’re up early this morning, take a few minutes to watch the skies for the peak of the Coma Berenicid meteor shower. Although the activity for this one is fairly weak, with an average fall rate of about seven per hour, it still warrants study.

So what makes this particular shower of interest? Noted first in 1959, the stream was eventually tied in 1973 to another minor shower bearing the same orbit known as the December Leo Minorids. As we know, meteoroid streams are traditionally tied to the orbit of a comet, and in this case the comet was unconfirmed! Observed in 1912 by B. Lowe, an Australian amateur astronomer, the comet was officially designated as 1913 I and was only seen four times before losing it to sunrise. Using Lowe’s observations, independent researchers computed the comet’s orbit and it was basically forgotten about until 1954. At that time, Fred Whipple was studying meteoroid orbits and made the association between his photographic studies and the enigmatic comet Lowe. By continuing to observe the annual shower, it was derived that the orbital period of the comet was about 75 years, but the two major streams occurred about 27 and 157 years apart. Thanks to the uneven dispersion of material, it may be another decade before we see some real activity from this shower, but even one meteor can make your day!

And if you want to make your “night” an early one, why not trying looking for another odd meteor shower? Tonight will be the peak of the Delta Arietids! These unusual meteors also bear a resemblance to last week’s Geminids, for the source of the stream appears to be a sun-grazing asteroid named Icarus. The hourly fall rate will be about 12 fast and bright “shooting stars”, but the Moon will interfere since it is so close to the radiant. Be sure to watch early as the constellation of Aries will be in the best position for only a few hours after dark. Have a telescope? Then be sure to visit with Madam Selene while out, because the “Straight Wall” will be making its one night stand parallel to the terminator. Look for its thread-thin black shadow just north of the emerging Tycho.

Tuesday, December 21 – This morning marks the point of winter solstice for the northern hemisphere – the time of year where the Sun appears furthest south. For parents, educators or just those who appreciate physically observing the wonders of astronomy, today would be a good time to start a very simple – and very pleasing – experiment. By placing a stake into the ground, or using a stationery object like a fence or sign post, measure the length of the shadow at noon. Write down your measurements, or cut and tag a piece of string with the date. Around every two weeks or so, repeat the process and enjoy the results!

Mira, Mira on the wall… Who’s the strangest star of all? You are, Omicron Ceti. Tonight we’re going to use the nine day old Moon to help guide us to one of the most interesting stars in the sky – Mira! Over 400 years ago, David Fabricus identified Mira, a.k.a. “the Beautiful One”, to be the very first variable star. But what exactly is it? At the time of its discovery, it was thought to be a nova. Cataloged by Bayer seven years later as 4th magnitude Omicron Ceti, imagine the surprise as it “disappeared” from unaided eye visibility! At minimum Mira is around magnitude 9, but within 331 days can flux as high as 3rd or 4th magnitude and has been known to even reach the brightness of Aldeberan.

As a binary system, Mira A is a red giant that goes through some intense changes during its cycle. As one of the coolest of the red stars at minimum, its hot, blue, sub-dwarf companion actually has twice the mass of the primary star. Is it possible that this tiny companion’s extreme gravitation and heat could affect Mira? As Omicron continues to deplete its hydrogen, the interior “pulses” causing it to become more than 100 times brighter and expand more than 700 times the size of our own Sun. In late 1997, Mira became the second star to be resolved by the Hubble Space Telescope and showed a very strange extension towards its companion star.

So how bright will it be tonight? Ah, my friends… That is the joy of discovery!

Wednesday, December 22 – Up early? Fantastic! In the pre-dawn hours of this morning, we have two treats for you – the return of Mercury and the Ursid meteor shower! Cruising around the Sun about every thirteen and a half years, Comet 8P/Tuttle sheds a little skin. Although it never passes inside of Earth’s orbit, some six years later we pass through its debris stream. Not so unusual? Then think again, because it takes as much as six centuries before the meteoroid trail is effected enough by Jupiter’s gravitation to pass into our atmosphere.

Although the Moon will interfere with watching this circumpolar meteor shower, the hours before dawn could see activity of up to 12 per hour. By keeping watch on the constellation of Ursa Major, you just might spot one of these slow moving, 600 year old travelers that make their path only halfway between us and the Moon!

Before dawn this morning, take a look down low on the horizon and say welcome back to Mercury. Above it, and leading the way is bright Venus. For telescopic observers, the real treat will be to see how differently each planet is phased. Venus will appear highly gibbous, while Mercury will only be about one-third illuminated. Keep watch on this pair in the days ahead as they swap places in the sky!

Thursday, December 23 – Tonight exploring the Moon will be in order as one of the most graceful and recognizable lunar features will be prominent – Gassendi. As an ancient mountain walled plane that sits proudly at the northern edge of Mare Humorum, Gassendi sports a bright ring and a triple central mountain peak that are within the range of binoculars. Telescopic viewers will appreciate Gassendi at high power to view how its southern border has been eroded by lava flow and the many riles and ridges that exist inside the crater and the presence of the younger Gassendi A on north wall. While viewing the Mare Humorum area, keep in mind that we are looking at an area about the size of the state of Arkansas. It is believed that a planetoid collision originally formed Mare Humorum. The incredible impact crushed the surface layers of the Moon resulting in a concentric “anticline” that can be traced twice the size of the original impact area. The floor of this huge crater then filled in with lava and was once thought to have a greenish appearance but in recent years have more accurately been described as reddish. That’s one mighty big crater!

Friday, December 24 – Twas the night before Christmas and all through the house, not a creature was stirring… Except for the mouse with the telescope who wants to see a multiple star system! Why don’t we join him tonight and have a look at a very nice and easily resolved, Sigma Orionis.

This particular system is easily found without a map. By identifying the three “belt” stars of Orion, go to the easternmost – Alnitak – and Sigma is the first star south of it. In the telescope you will find a beautiful combination of four stars. The 3.8 magnitude white primary commands attention. With a designation of A/B, this super-massive and extremely bright pair are far too close (about 100 AU apart) to be split with a small scope. Looking 11″ to the southwest, you will discover the 10th magnitude white “C” star and you will see the 7.2 magnitude red “D” star 13″ to the east. Further away yet at a distance of 42″ to the east/northeast is the 6.5 magnitude blue “E” star.

Sharp-eyed observers will also note another multiple system in the same field of view to the northwest. This is Struve 761. As an “all white” system of similar magnitudes, you will see two residing east/west of each other and the third companion to the north. What we are looking at is a system that is about 1,500 light years away from us in the rich, star-forming region of Orion. Give that mouse a piece of cheese!

Saturday, December 25 – In keeping with the season, tonight’s astronomical object is a celebration of both starlight and asterism. Located 10 degrees east of Betelgeuse, the NGC 2264 will be a challenging object thanks to tonight’s near-full Moon, but the results will be quite worth it! Also known as “the Christmas Tree” cluster, this bright asterism of approximately 20 bright stars and over a 100 fainter ones is embroiled in a faint nebula that will be lost to bright skies, leaving only the delightful “Christmas Tree” shape adorned with stars. The very brightest of these stars, S Monoceros, is fifth magnitude and will show clearly in the finder scope and as a double at magnification. Steady skies will reveal that the “star” and the top of our “tree” is also a visual double and home to the beautiful “Cone Nebula”! Many of the stars will also appear to have companions, as well as tints of silver as gold. The visual effect of this splendid open cluster (as seen in this sketch by Jeff Barbour) is well worth the challenge it presents. Happy Holidays!

Sunday, December 26 – Did you get a new telescope? Then enjoy tonight’s full Moon! Although it is very bright, it is also the easiest of astronomical targets and will show many prominent features, bright rays and expansive plains of maria. If you are itching to explore, but unfamiliar with the sky, the Moon will offer to be your guide to one of the most exciting planets for the beginner – Saturn!

With the Moon in the constellation of Gemini tonight, you will see three “stars” gathered to the east. Point your telescope at the southern-most of this trio and enjoy the “Lord of the Rings”. Even small telescopes can appreciate the broad ring system, but there is also a treat tonight as well. Appearing to “follow” Saturn across the sky is its easily spotted moon, Titan!

I would like to thank all of you who have taken the time to write! Your observations of Comet Macholz have been wonderful, so please continue to observe it despite the Moon. I deeply appreciate all the kind words I have received. Do not be afraid to ask questions or share an observation. This column is all about you! Until next week? I wish you the very best of the season. Keep looking up and enjoying the wonders of our Universe! Light speed… ~Tammy Plotner

What’s Up This Week – Dec 13 – Dec 19, 2004

Image credit: George Varros
Monday, December 13 – Tonight will be one of the most hauntingly beautiful and most mysterious displays of celestial fireworks all year – the Geminid meteor shower. First noted in 1862 by Robert P. Greg in England, and B. V. Marsh and Prof. Alex C. Twining of the United States in independent studies, the annual appearance Geminid stream was weak, producing no more than a few per hour, but it has grown in intensity during the last century and a half. By 1877 astronomers were realizing a new annual shower was occurring with an hourly rate of about 14. At the turn of the century it had increased to an average of over 20, and by the 1930s from 40 to 70 per hour. Only eight years ago observers recorded an outstanding 110 per hour during a moonless night… And now it is moonless again!

So why are the Geminids such a mystery? Most meteor showers are historic, documented and recorded for hundred of years, and we know them as being cometary debris. When astronomers first began looking for the Geminids parent comet, they found none. After decades of searching, it wasn’t until October 11,1983 that Simon Green and John K. Davies, using data from NASA’s Infrared Astronomical Satellite, detected an orbital object that was the next night confirmed by Charles Kowal that matched the Geminid meteoroid stream. But this was no comet, it was an asteroid. Originally designated as 1983 TB, but later renamed 3200 Phaethon, this apparently rocky solar system member has a highly elliptical orbit that places it within 0.15 AU of the Sun about every year and half. But asteroids can’t fragment like a comet – or can they? Original hypothesis were that since Phaethon’s orbit passes through the asteroid belt, that it may have collided with other asteroids causing rocky debris. This sounded good, but the more we studied the more we realized the meteoroid “path” occurred when Phaethon neared the Sun. So now our asteroid is behaving like a comet, yet it doesn’t develop a tail.

So what exactly is this “thing”? Well, we do know that 3200 Phaethon orbits like a comet, yet has the spectral signature of an asteroid. By studying photographs of the meteor showers, scientists have determined that the meteors are more dense than cometary material and not as dense as asteroid fragments. This leads us to believe that Phaethon is probably an extinct comet that has gathered a thick layer of interplanetary dust during its travels, yet retains the ice-like nucleus. Until we are able to take physical samples of this “mystery”, we may never fully understand what Phaethon is, but we can fully appreciate the annual display it produces!

Thanks to the wide path of the stream, folks the world over get an opportunity to enjoy the show. The traditional peak time is tonight as soon as the constellation of Gemini appears around mid-evening and lasts through tomorrow morning. The radiant for the shower is right around bright star Castor, but meteors can originate from many points in the sky. From around 2:00 a.m. until dawn (when our local sky window is aimed directly into the stream) it is possible that we can see (animated clip by George Varros.) about one “shooting star” every 30 seconds. The most successful of observing nights are ones where you are comfortable, so be sure to use a reclining chair or pad the ground while looking up. Please get away from light sources when possible – it will triple the amount of meteors you see, dress warmly, take along refreshments and just enjoy the incredible and mysterious Geminids!

Tuesday, December 14 – So if you thought last night was great, then don’t plan on getting extra sleep tonight as we wait out the two-day old Moon to set and Orion to rise. Tonight we’re going to locate and explore Don Macholz tenth comet discovery – C/2004 Q2! This is definitely a “not to be missed” treat. Even the most modest of binoculars will reveal this spectacular comet. Located tonight on the Eridanus border you can easily locate Q2 by identifying the constellation of Lepus below Orion and simply sweeping the skies a short distance to the west. You cannot miss Macholz. It’s that bright and that easy!

Holding a rough magnitude of 5, Comet Macholz is visible to the naked eye at a dark site, but is sufficiently bright enough to be caught with small binoculars under less than perfect conditions. What can you expect to see? The coma (at the time of my observances prior to this article) is wonderfully huge and about the size of that great globular cluster, M13, yet it is definitely brighter! Veteran comet observers will appreciate its concentrated nucleus, extensive coma and twin dust and ion tails. For the novice, Macholz will indeed appear like a large, unresolvable globular cluster with a bright core, but look up, up and away at the stretch of tail. It’s the finest (in my humble opinion) since Ikeya/Zhang! If the constellation of Lepus is too low for your location, don’t worry. The wonderful Macholz will continue in the days ahead to climb northward until it reaches Taurus by month’s end. This one is awesome!

Wednesday, December 15, 2004 – For early evening viewers, tonight’s Moon will give a great opportunity to visit telescopically with some smaller features located within the fully disclosed Mare Crisium area. Near the terminator, look for two bright mountainous areas on the central western border of Crisium known as Olivium and Lavinium Promentoriums. Voyaging from this point toward the east across Crisium’s smooth floor, we will see the small punctuations of Craters Picard to the south and Pierce to the north. See how many nights you are still able to make out these features!

Thursday, December 16 – Tonight the Moon is once again our prominent sky feature, so why not venture there and visit one of the oldest features left on our visible lunar side? Start by identifying two prominent craters in the southeast quadrant – Metius and Fabricus. While viewing the area around these craters, note that Frabricus’ walls actually intrude upon Metius pointing to its younger age of formation. Around Fabricus, but not including Metius is the boundary of a mountain walled plain that extends into the terminator. High power and stable conditions will reveal many breaks in its hexagonal walls and its floor will be marred by many smaller craters and fissures. This is crater Jannsen, and in all probability is one of the oldest craters left on the Moon. Look for three prominent interior craters as well as an ancient rimae that will be at the shadow’s edge. It may not seem exciting, but remember crater Jannsen could be as much as five billion years old!

Friday, December 17 – As we continue our lunar exploration tonight, look for the “three ring circus” of easily identified craters Theophilus, Cyrillus and Catherina. It is here that you will find a very unique highlight – a very conspicuous lunar feature that was never officially named! Cutting its way across Mare Nectaris from Theophilus to shallow crater Beaumont in the south will appear a long, thin, bright line. What you are looking at is an example of lunar dorsum – nothing more than a wrinkle or low ridge. Chances are probably good that this ridge is just a “wave” in the lava flow that congealed when Mare Nectaris was formed and it is quite striking tonight because of the lighting angle. Has it been named? Yes. It is unofficially known as the “Dorsae Beaumont”, but whatever it may be called, it is surely a distinct feature that I think you’ll enjoy!

Saturday, December 18 – There’s still plenty of Moon to explore tonight, so why don’t we try locating an area where many lunar exploration missions made their mark? Binoculars will easily reveal the fully disclosed areas of Mare Serenitatis and Mare Tranquillitatis, and it is where these two vast lava plains converge that we will set our sites. Telescopically you will see a bright “peninsula” westward of where the two conjoin that extends toward the east, just off that look for bright and small crater Pliny. It is near this rather inconspicuous feature that the remains Ranger 6 lay forever preserved when it crashed on February 2, 1964. Unfortunately, technical errors occured and it was never able to transmit lunar pictures. Not so Ranger 8! On a very successful mission to the same relative area, this time we received 7137 “postcards from the Moon” in the last 23 minutes before hard landing. On the “softer side”, Surveyor 5 also touched down near this area safely after two days of malfunctions on September 10, 1967. Incredibly enough, the tiny Surveyor 5 endured temperatures of up to 283 degrees F, but was able to spectrographically analyze the area’s soil… And by the way, it also managed to televise an incredible 18,006 frames of “home movies” from its distant lunar locale.

Sunday, December 19 – Tonight’s outstanding lunar feature is easily seen in binoculars and a treasure-trove of detail to the telescope. Located roughly one-third the way from south to north limb, Crater Albategnius will stand out in bold relief near the terminator. A fine challenge for binoculars will be to see if you can make out its bright central peak from its darker lava covered floor. Telescopically, Albategnius is a real treat! Also an ancient formation, look for the large number of younger craters in its ruined walls. The largest of these is Crater Klein, but there are myriad others. A nice test of your optics and abilities to discern small features is to look for three shallow depressions east of the central peak. Good luck!

Until next week? Remember that many deep sky objects are still visible despite the Moon, so keep looking up and enjoying the wonders of our own Universe! Wishing you clear, dark skies and light speed… ~Tammy Plotner