What’s Up this Week: December 3 – December 9, 2007

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Monday, December 3 – Today in 1971, the Soviet Mars 3 became the first spacecraft to make a soft landing on the red planet, and two years later on this same date the Pioneer 10 mission became the first spacecraft to fly by Jupiter. One year later on this same date? Pioneer 11 did the same thing!

Tonight let’s familiarize ourselves with the vague constellation of Fornax. Its three brightest stars form a shallow V just south of the Cetus/Eridanus border and span less than a handwidth of sky. Although it’s on the low side for northern observers, there is a wealth of sky objects in this area.

Try having a look at the easternmost star – 40-light-year distant Alpha. At magnitude 4, it is not easy, but what you’ll find there is quite beautiful. For binoculars, you’ll see a delightful cluster of stars around this long-term binary – but telescopes will enjoy it as a great golden double star! First measured by John Herschel in 1835, the distance between the pair has narrowed and widened over the last 172 years and it is suspected its orbital period may be 314 years. While the 7th magnitude secondary can be spotted with a small scope – watch out – because it may also be a variable which drops by as much as a full magnitude!

Tuesday, December 4 – Today in 1978, the Pioneer/Venus Orbiter became the first spacecraft to orbit Venus. And in 1996, the Mars Pathfinder mission was launched!

For larger telescopes, set sail for Beta Fornacis tonight and head 3 degrees southwest (RA 02 39 42.5 Dec -34 16 08.0) for a real curiosity – NGC 1049.

At magnitude 13, this globular cluster is a challenge for even large scopes – and with good reason. It isn’t in our galaxy. This globular cluster is a member of the Fornax Dwarf Galaxy – a one degree span that’s so large it was difficult to recognize as extra-galactic – or at least it was until the great Harlow Shapely figured it out!

NGC 1049 was first discovered and cataloged by John Herschel in 1847, only to be reclassified as “Hodge 3” in a 1961 study of the system’s five globular clusters by Paul Hodge. Since that time, yet another globular has been discovered! Good luck…

Wednesday, December 5 – Up before dawn? Then check out the skies because the stars of spring are returning! Let the waning Moon be your guide as it and Spica are only about two degrees apart!

How about something a little more suited to the mid-sized scope tonight? Set your sights on Alpha Fornacis and let’s head about 3 fingerwidths northeast (RA 03 33 14.65 Dec -25 52 18.0) for NGC 1360.

In a 6″ telescope, you’ll find the 11th magnitude central spectroscopic double star of this planetary nebula to be very easy – but be sure to avert because the nebula itself is very elongated. Like most of my favorite things, this planetary is a rule-breaker since it doesn’t have an obvious shell structure. But why? Rather than believe it is not a true planetary by nature, studies have shown that it could quite possibly be a very highly evolved one – an evolution which has allowed its gases to begin to mix with the interstellar medium.

Although faint and diffuse for northern observers, those in the south will recognize this as Bennett 15!

Thursday, December 6 – For northern observers clamoring for brighter stellar action, look no further tonight than the incredible “Double Cluster” about four fingerwidths southeast of Delta Cassiopeiae. At a dark sky site, this incredible pair is easily located visually and stunning in any size binoculars and telescopes.

As part of the constellation of Perseus, this double delight is around 7000 light-years away and less than 100 light-years separates the pair. While open clusters in this area are not really a rarity, what makes the “Double Cluster” so inviting is the large amount of bright stars within each of them.

Well known since the very beginnings of astronomy, take the time to have a close look at both Chi (NGC 884) and H Persei very carefully. Note how many colorful stars you see, and the vast array of double, multiple and variable systems!

Friday, December 7 – Today is the birthday of Gerard Kuiper. Born 1905, Kuiper was a Dutch-born American planetary scientist who discovered moons of both Uranus and Neptune. He was the first to know that Titan had an atmosphere, and he studied the origins of comets and the solar system.

Tonight let’s honor his achievements as we have a look at another bright open cluster known by many names: Herschel VII.32, Melotte 12, Collinder 23, and NGC 752. You’ll find it three fingerwidths south (RA 01 57.8 Dec +37 41) of Gamma Andromedae…

Under dark skies, this 5.7 magnitude cluster can just be spotted with the unaided eye, is revealed in the smallest of binoculars, and can be completely resolved with a telescope. Chances are it was first discovered by Hodierna over 350 years ago, but it was not cataloged until Sir William gave it a designation in 1786. But give credit where credit is due… For it was Caroline Herschel who observed it on September 28, 1783!

Containing literally scores of stars, galactic cluster NGC 752 could be well over a billion years old, strung out in chains and knots in an X pattern of a rich field. Take a close look at the southern edge for orange star 56: while it is a true binary star, the companion you see is merely optical. Enjoy this unsung symphony of stars tonight!

Saturday, December 8 – Today in history (1908) marks “first light” for the 60″ Hale Telescope at Mt. Wilson Observatory. Not only was it the largest telescope of the time, but it ended up being one of the most productive of all. Almost 100 years later, the 60″ Hale is still in service as a public outreach instrument. If we could use the 60″ tonight to study, where would we go? My choice would be the Fornax Galaxy Cluster!

Containing around 20 galaxies brighter than 13th magnitude in a one degree field, here is where a galaxy hunter’s paradise begins! About a degree and a half north of Tau Fornacis is the large, bright and round spiral NGC 1398. A little more than a degree west-northwest is the easy ring of the planetary nebula NGC 1360. Look for the concentrated core and dark dustlane of NGC 1371 a degree north-northeast – or the round NGC 1385 which accompanies it. Why not visit Bennett 10 or Caldwell 67 as we take a look at NGC 1097 about 6 degrees west-southwest of Alpha? This one is bright enough to be caught with binoculars!

Telescopes will love NGC 1365 at the heart of the cluster proper. This great barred spiral gives an awesome view in even the smallest of scopes. As you slide north, you will encounter a host of galaxies, NGCs 1386, 1389, 1404, 1387, 1399, 1379, 1374, 1381 and 1380. There are galaxies everywhere! But, if you lose track? Remember the brightest of these are two ellipticals – 1399 and 1404. Have fun!

Sunday, December 9 – Southern Hemisphere viewers, you’re in luck again on a New Moon night! This is the maximum of the Puppid-Velid meteor shower. With an average fall rate of about 10 per hour, this particular meteor shower could also be visible to those far enough south to see the constellation of Puppis. Very little is known about this shower except that the streams and radiants are very tightly bound together. Since studies of the Puppid-Velids are just beginning, why not take the opportunity to watch? Viewing will be possible all night long and although most of the meteors are faint, this one is known to produce an occasional fireball.

Since we’re favoring the south tonight, let’s set northern observers toward a galaxy cluster – Abell 347 – located almost directly between Gamma Andromedae and M34. Here you will find a grouping of at least a dozen galaxies that can be fitted into a wide field view. Let’s tour a few…

The brightest and largest is NGC 910, a round elliptical with a concentrated nucleus. To the northwest you can catch faint, edge-on NGC 898. NGC 912 is northeast of NGC 910, and you’ll find it quite faint and very small. NGC 911 to the north is slightly brighter, rounder, and has a substantial core region. NGC 909 further north is fainter, yet similar in appearance. Fainter yet is more northern NGC 906, which shows as nothing more than a round contrast change. Northeast is NGC 914, which appears almost as a stellar point with a very small haze around it. To the southeast is NGC 923 which is just barely visible with wide aversion as a round contrast change. Enjoy this Abell quest!

What’s Up this Week: November 26 – December 2, 2007

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Monday, November 26 – Today in 1965 marked the launch of the first French satellite – Asterix 1. Today is also the seventh anniversary of the discovery of the meteorites SAU 005 & 008: the “Mars Meteorites.” These meteorites are known to be of Martian origin because of gases preserved in the glassy material of their interior. They were hurled into space some 600,000 years ago when a probable asteroid impact on Mars tossed them high enough to escape the planet’s gravity, and they were captured by our gravity these many thousands of years later. They are just two of the 32 meteorites found on Earth which have been positively determined from their chemical compositions to be of Martian origin.

Thanks to just a slightly later rise of the Moon, let’s return again to Cassiopeia and start at the central-most bright star, Gamma. Four degrees southeast is our marker for this starhop, Phi Cassiopeiae. By aiming binoculars or telescopes at this star, it is very easy to locate an interesting open cluster, NGC 457, because they will be in the same field of view.

This bright and splendid galactic cluster has received a variety of names over the years because of its uncanny resemblance to a figure. Some call it an “Angel,” others see it as the “Zuni Thunderbird;” I’ve heard it called the “Owl” and the “Dragonfly,” but perhaps my favorite is the “E.T. Cluster,” As you view it, you can see why! Bright Phi and HD 7902 appear like “eyes” in the dark and the dozens of stars that make up the “body” appear like outstretched “arms” or “wings.” (For E.T. fans? Check out the red “heart” in the center.)

All this is very fanciful, but what is NGC 457, really? Both Phi and HD 7902 may not be true members of the cluster. If 5th magnitude Phi were actually part of this grouping, it would have to have a distance of approximately 9300 light-years, making it the most luminous star in the sky, far outshining even Rigel! To get a rough of idea of what that means, if we were to view our own Sun from this far away, it would be no more than magnitude 17.5. The fainter members of NGC 457 comprise a relatively young star cluster that spans about 30 light-years. Most of the stars are only about 10 million years old, yet there is an 8.6 magnitude red supergiant in the center. No matter what you call it, NGC 457 is an entertaining and bright cluster that you will find yourself returning to again and again. Enjoy!

Tuesday, November 27 – Tonight let’s take advantage of early dark and venture further into Cassiopeia. Returning to Gamma, we will move towards the southeast and identify Delta. Also known as Ruchbah, this long-term and very slight variable star is about 45 light-years away, but we are going to use it as our marker as we head just one degree northeast and discover M103.

As the last object in the original Messier catalog, M103 (NGC 581) was actually credited to MÈchain in 1781. Easily spotted in binoculars and small scopes, this rich open cluster is around magnitude 7, making it a prime study object. At about 8000 light-years away and spanning approximately 15 light-years, M103 offers up superb views in a variety of magnitudes and colors, with a notable red in the south and a pleasing yellow and blue double to the northwest.

Viewers with telescopes and larger binoculars are encouraged to move about a degree and half east of M103 to view a small and challenging chain of open clusters, NGCs 654, 663 and 659! Surprisingly larger than M103, NGC 663 is a lovely fan-shaped concentration of stars with about 15 or so members that resolve easily to smaller aperture. For the telescope, head north for NGC 654, (difficult, but not impossible to even a 114mm scope) which has a bright star on its southern border. South of NGC 663 is NGC 659 which is definitely a challenge for small scopes, but its presence will be revealed just northeast of two conspicuous stars in the field of view.

If you are out when the Moon rises tonight, enjoy seeing Mars very nearby – less than 2 degrees away! And speaking of degrees, today is also the birthday of Anders Celsius – born in 1701.

Wednesday, November 28 – Once again utilizing early darkness, let’s go back to Cassiopeia. Remembering Alpha’s position as the westernmost star, go there with your finderscope or binoculars and locate bright Sigma and Rho (each has a dimmer companion). They will appear to the southwest of Alpha. It is between these two stars that you will find NGC 7789 (RA 23 57 24.00 Dec +56 42 30.0).

Absolutely one of the finest of rich galactic opens bordering on a loose globular, NGC 7789 has a population of about 1000 stars and spans a mind-boggling 40 light-years. At well over a billion years old, the stars in this 5000 light-year distant galactic cluster have already evolved into red-giants or super-giants. Discovered by Caroline Herschel in the 18th century, this huge cloud of stars has an average magnitude of 10, making it a great large binocular object, a superb small telescope target, and a total fantasy of resolution for larger instruments.

Tonight in 1659, Christian Huygens was busy at the eyepiece – but he wasn’t studying Saturn. This was the first time any astronomer had seen dark markings on Mars!

Thursday, November 29 – Today in 1961, Mercury 5 launched Enos the Chimp into fame!

With a short time until the Moon rises tonight, why not journey with me once again to Cassiopeia? We will start our studies with the western-most of the bright stars – Beta. Also known as “Caph,” Beta Cassiopeiae is approximately 45 light-years away and is known to be a rapid variable. Viewers with larger telescopes are challenged to find the 14th magnitude optical companion to Caph at about 23″ in separation. Tonight, using our previous study stars Alpha and Beta, we are going to learn to locate a Messier object with ease! By drawing an imaginary line between Alpha and Beta, we extend that line the same distance and angle beyond Beta and find M52.

Found on September 7, 1774 by Charles Messier, this magnitude 7 galactic cluster is easily seen in both binoculars and small telescopes. Comprised of roughly 200 members, this open cluster is roughly 3,000 light-years distant and spans approximately 10-15 light-years. Containing stars of several different magnitudes, larger telescopes will easily perceive blue components as well as orange and yellow. Also known as NGC 7654, M52 is a young, very compressed cluster whose approximate age is about the same as the Pleiades.

For those with large telescopes wanting a challenge? Try spotting a faint patch of nebulosity just 36′ to the southwest. This is NGC 7635, more commonly known as the “Bubble Nebula.” Best of luck!

Friday, November 30 – If you are up before dawn, Look for bright Venus and cool, blue Spica less than a fistwidth apart – and look for the Moon and Regulus! Less than half a degree of separation means a possible occultation event, so be sure to check IOTA information. Just as a curiosity, on this day in 1954, Elizabeth Hodges was struck by a five kilogram meteorite in Alabama. Duck!

Tonight we will haunt Cassiopeia one last time – with studies for the seasoned observer. Our first challenge of the evening will be to return to Gamma where we will locate two patches of nebulosity in the same field of view. IC 59 and IC 63 are challenging because of the bright influence of the star, but by moving the star to the edge of the field of view you may be able to locate these two splendid small nebulae. If you do not have success with this pair, why not move on to Alpha? About one and a half degrees due east, you will find a small collection of finderscope stars that mark the area of NGC 281 (RA 00 52 25.10 Dec +56 33 54.0). This distinctive cloud of stars and ghostly nebulae make this NGC object a fine challenge!

The last things we will study are two small elliptical galaxies that are achievable in mid-sized scopes. Locate Omicron Cassiopeiae about 7 degrees north of M31 and discover a close galactic pair that is associated with the Andromeda group – NGC 185 (RA 00 38 57.40 Dec +48 20 14.4) and NGC 147 (RA 00 33 11.79 Dec +48 30 24.8).

The constellation of Cassiopeia contains many, many more fine star clusters, and nebulae – and even more galaxies. For the casual observer, simply tracing over the rich star fields with binoculars is a true pleasure, for there are many bright asterisms best enjoyed at low power. Scopists will return to “rock with the Queen” year after year for its many challenging treasures. Enjoy it tonight!

Saturday, December 1 – Born today in 1811 was Benjamin (Don Benito) Wilson. He was the namesake of Mt. Wilson, California – home to what once were the largest telescopes in the world – the 60″ Hale and the 100″ Hooker. Later, three solar telescopes were added on the mountain – two of which are still in use – as well as the CHARA array and active interferometers. It was here that Edwin Hubble first realized the “nebulae” were distant galaxies and discovered Cepheid variables in them. As we approach the end of our SkyWatching year together, let us pretend the skies are still as dark as they were on Mt. Wilson as we aim our binoculars and telescopes towards one of the most elusive galaxies of all – M33.

Located about one-third the distance between Alpha Triangulum and Beta Andromedae (RA 01 33.9 Dec +30 39), this member of our Local Group was probably first seen by Hodierna, but was recovered independently by Messier some 110 years later. Right on the edge of visibility unaided, M33 spans about 4 full moon widths of sky, making it a beautiful binocular object and a prime view in a low power telescope.

Smaller than the Milky Way and the Andromeda Galaxy, the Triangulum galaxy is about average in size, but anything but average to study. So impressed was Herschel that he gave it its own designation of H V.17 after having cataloged one of its bright star forming regions as H III.150! In 1926, Hubble also studied M33 at Mt. Wilson with the Hooker telescope during his work with Cepheid variables. Larger telescopes often “can’t see” M33 with good reason – it overfills the field of view – but what a view! Not only did Herschel discover a region much like our own Orion Nebula, but the entire galaxy contains many NGC and IC objects (even globular clusters) that can be seen with a larger scope.

Although M33 might be 3 million light-years away, tonight it’s as close as your own dark sky site…

Sunday, December 2 – If you are awake before dawn, enjoy the beauty of Saturn and the Moon as they dance along the ecliptic plane together. For most viewers, the tranquil pair will only be about a fingerwidth apart. Today in 1934, the largest mirror in telescope history began its life as the blank for the 200″ telescope was cast in Corning, NY.

The 200″ would play another important role as Edwin Hubble continued on at Palomar Observatory. Thanks to his work there, we now understand “Hubble’s Law” – the expansion of the Universe. Tonight let us honor that great mind as we take a look at a galaxy that’s receding from us – NGC 1300.

Located about a thumb’s width north of Tau4 Eridani (RA 03 19.7 Dec -19 25), this is probably the most incredible barred spiral you will ever encounter. At magnitude 10, it will require at least a 4.5″ telescope in northern latitudes, but can probably be spotted with binoculars in the far south.

At 75 million light-years away, NGC 1300’s central bar alone is larger than the Milky Way, and this galaxy has been intensively studied because the manner of its formation was so similar that of to our own. Although it is so distant, it is seen face-on – allowing us a look at how this formation occurs without looking through the gas and dust which block our own central view. Enjoy this one’s fantastic structure!

What’s Up this Week: November 19 – November 25, 2007

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Monday, November 19 – Even if you only use binoculars tonight, you can’t miss the beautiful C-shape of Sinus Iridium as it comes into view on the lunar surface. As we have learned, the mountains that ring it are called the Juras, and the crater punctuating them is named Bianchini. Do you remember what the bright tips of the opening into the “Bay of Rainbows” are called? That’s right: Promontorium LaPlace to the northeast and Promontorium Heraclides to the southwest. Now take a good look at Heraclides… Just south of here is where Luna 17 landed, leaving the Lunokhod rover to explore!

Now turn your eyes or binoculars just west of bright Aldebaran and have a look at the Hyades Star Cluster. While Aldebaran appears to be part of this large, V-shaped group, it is not an actual member. The Hyades cluster is one of the nearest galactic clusters, and it is roughly 130 light-years away in the center. This moving group of stars is drifting slowly away towards Orion, and in another 50 million years it will require a telescope to view!

Tuesday, November 20 – Today celebrates another significant astronomer’s birth – Edwin Hubble. Born 1889, Hubble became the first American astronomer to identify Cepheid variables in M31 – which in turn established the extragalactic nature of the spiral nebulae. Continuing with the work of Carl Wirtz, and using Vesto Slipher’s redshifts, Hubble then could calculate the velocity-distance relation for galaxies. This has become known as “Hubble’s Law” and demonstrates the expansion of our Universe.

Tonight we’re going to ignore the Moon and head just a little more than a fistwidth west of the westernmost bright star in Cassiopeia to have a look at Delta Cephei (RA 22 29 10.27 Dec +58 24 54.7). This is the most famous of all variable stars and the granddaddy of all Cepheids. Discovered in 1784 by John Goodricke, its changes in magnitude are not due to a revolving companion – but rather the pulsations of the star itself.

Ranging over almost a full magnitude in 5 days, 8 hours and 48 minutes precisely, Delta’s changes can easily be followed by comparing it to nearby Zeta and Epsilon. When it is its dimmest, it will brighten rapidly in a period of about 36 hours – yet take 4 days to slowly dim again. Take time out of your busy night to watch Delta change and change again. It’s only 1000 light-years away, and doesn’t even require a telescope! (But even binoculars will show its optical companion…)

Wednesday, November 21 – Tonight the gibbous Moon will dominate the sky. If you haven’t had a chance to log some features like Copernicus, Gassendi, Tycho and Plato – be sure to pick them up before the glare overpowers them. While you’re there, be sure to look for “the Man in the Moon!”

Now, let’s continue our stellar studies with the central-most star in the lazy “W” of Cassiopeia – Gamma…

At the beginning of the 20th century, the light from Gamma appeared to be steady, but in the mid-1930s it took an unexpected rise in brightness. In less than 2 years it jumped by a magnitude! Then, just as unexpectedly, it dropped back down again in roughly the same amount of time. A performance it repeated some 40 years later!

Gamma Cassiopeiae isn’t quite a giant and is still fairly young on the evolutionary scale. Spectral studies show violent changes and variations in the star’s structure. After its first recorded episode, it ejected a shell of gas which expanded Gamma’s size by over 200% – yet it doesn’t appear to be a candidate for a nova event.

The best estimate now is that Gamma is around 100 light-years away and approaching us a very slow rate. If conditions are good, you might be able to telescopically pick up its disparate 11th magnitude visual companion, discovered by Burnham in 1888. It shares the same proper motion – but doesn’t orbit this unusual variable star. For those who like a challenge, visit Gamma again on a dark night! Its shell left two bright (and difficult!) nebulae, IC 59 and IC 63, to which we will return at the end of the month.

Thursday, November 22 – As our observing year draws to a close, let’s take another look at a feature you might have missed – Wargentin. Located in the southwest quadrant on the terminator just south of the larger crater Schickard, we return again because Wargentin is one of the Moon’s most well-known curiosities. Able to be captured in binoculars, but best seen through a telescope at high power, really take a look at what was once a normal small crater! Unlike most craters, Wargentin’s walls were solid – able to contain the lava which eventually filled it to a height of 84 meters above the lunar surface.

While at first you might not notice, compare it to nearby Nasmyth and Phocylides. While both of these craters go below the surface, they also contain interior strikes – Wargentin has none! Except for a gentle, unnamed rille across its elevated surface, Wargentin is smooth.

While we still have about a month until it reaches opposition, the “Red Planet” is always worthy of a little attention. While Mars isn’t at its closest right now, this will be the only time this year that we can view it in the evening. Catch it now – before the Moon catches up with it in the days ahead!

Friday, November 23 – Tonight in 1885, the very first photograph of a meteor shower was taken. Also, the weather satellite TIROS II was launched on this day in 1960. Carried to orbit by a three-stage Delta rocket, the “Television Infrared Observation Satellite” was about the size of a barrel, testing experimental television techniques and infrared equipment. Operating for 376 days, Tiros II sent back thousands of pictures of Earth’s cloud cover and was successful in its experiments to control the orientation of the satellite spin and its infrared sensors. Oddly enough, a similar mission – Meteosat 1 – also became the first satellite put into orbit by the European Space Agency, in 1977 on this day. Where is all this leading? Why not try observing satellites on your own! Thanks to wonderful on-line tools from NASA you can be alerted by e-mail whenever a bright satellite makes a pass for your specific area. It’s fun!

Now, let’s explore tonight’s lunar feature – Galileo. It is a challenge for binoculars to spot this feature, but telescopes of any size capable of higher power will find it easily on the terminator in the west-northwest section of the Moon. Set in the smooth sands of Oceanus Procellarum, Galileo is a very tiny, eye-shaped crater and has a soft rille that accompanies it. It was named for the very man who first viewed and contemplated the Moon through a telescope. No matter what lunar resource you choose to follow, all agree that giving such an insignificant crater a great name like Galileo is unthinkable! For those of you familiar with some of the outstanding lunar features, read any good account of Galileo’s life and just look at how many spectacular craters were named for people he supported! We cannot change the names of lunar cartography, but we can remember Galileo’s many accomplishments each time we view this crater

Saturday, November 24 – Tonight it is Full “Frost Moon” and there is little doubt about how its name came to be! For those of you interested in viewing lunar features tonight, libration could be favorable to study a collection of shallow, dark craters known as Mare Australe. Located on the southeastern limb, this large binocular and telescopic object is well-worth looking for because it’s a challenge that isn’t always visible.

Ready to aim for a bullseye? Then head for the bright, reddish star Aldebaran. Set your eyes, scopes or binoculars there and let’s look into the “eye” of the Bull.

Known to the Arabs as Al Dabaran, or “the Follower,” Alpha Tauri took its name for the fact that it appears to follow the Pleiades across the sky. In Latin it was Stella Dominatrix, yet the old English knew it as Oculus Tauri, or very literally the “eye of Taurus.” No matter which source of ancient astronomy lore we explore, there are references to Aldeberan.

As the 13th brightest star in the sky, it almost appears from Earth to be a member of the V-shaped Hyades star cluster, but its association is merely coincidental, since it is about twice as close to us as the cluster. In reality, Aldeberan is on the small end as far as K5 stars go, and like many other orange giants could possibly be a variable. Aldeberan is also known to have five close companions, but they are faint and very difficult to observe with backyard equipment. At a distance of approximately 68 light-years, Alpha is only about 40 times larger than our own Sun and approximately 125 times brighter. To get a grasp on that size, think of it as being about the same size as the area Earth’s orbit! Because of its position along the ecliptic, Aldeberan is one of the very few stars of first magnitude that can be occulted by the Moon.

Sunday, November 25 – While Cassiopeia is in prime position for most northern observers, let’s return tonight for some additional studies. Starting with Delta, let’s hop to the northeast corner of our “flattened W” and identify 520 light-year distant Epsilon. For larger telescopes only, it will be a challenge to find this 12″ diameter, magnitude 13.5 planetary nebula I.1747 in the same field as magnitude 3.3 Epsilon!

Using both Delta and Epsilon as our “guide stars” let’s draw an imaginary line between the pair extending from southwest to northeast and continue the same distance until you stop at visible Iota. Now go to the eyepiece…

As a quadruple system, Iota will require a telescope and a night of steady seeing to split its three visible components. Approximately 160 light-years away, this challenging system will show little or no color to smaller telescopes, but to large aperture, the primary may appear slightly yellow and the companion stars a faint blue. At high magnification, the 8.2 magnitude “C” star will easily break away from the 4.5 primary, 7.2″ to the east-southeast. But look closely at that primary: hugging in very close (2.3″) to the west-southwest and looking like a bump on its side is the B star!

Dropping back to the lowest of powers, place Iota to the southwest edge of the eyepiece. It’s time to study two incredibly interesting stars that should appear in the same field of view to the northeast. When both of these stars are at their maximum, they are easily the brightest of stars in the field. Their names are SU (southernmost) and RZ (northernmost) Cassiopeiae and both are unique! SU is a pulsing Cepheid variable located about 1000 light-years away and will show a distinctive red coloration. RZ is a rapidly eclipsing binary that can change from magnitude 6.4 to magnitude 7.8 in less than two hours. Wow!

What’s Up this Week: November 12 – November 18, 2007

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Monday, November 12 – Can you spot the thin crescent of the Moon on the western horizon at sunset? Let Jupiter help you. Look for the slim appearance of Selene about 3 fingerwidths south.

Wouldn’t we all have loved to have been there in 1949 when the first scientific observations were made with the Palomar 5-meter (200-inch) telescope? Or to have seen what Voyager 1 saw as it made its closest approach to Saturn on this date in 1980? To watch Space Shuttle Columbia launch in 1981? Or even better, to have been around in 1833 – the night of the Great Leonid Meteor Shower! But this is here and now, so let’s make our own mark on the night sky as we view the Moon.

This evening have a look at the lunar surface and the southeast shoreline of Mare Crisium for Agarum Promontorium. To a small telescope it will look like a bright peninsula extending northward across the dark plain of Crisium’s interior, eventually disappearing beneath the ancient lava flow. Small crater Fahrenheit can be spotted at high power to the west of Agarum, and it is just southeast of there that Luna 24 landed. If you continue south of Agarum along the shoreline of Crisium you will encounter 15 kilometer high Mons Usov. To its west is a gentle rille known as Dorsum Termier – where the Luna 15 mission remains lie. Can you spot 23 kilometer wide Shapely further south?

While skies are fairly dark be sure to keep watch for members of the Pegasid meteor shower – the radiant is roughly near the Great Square. This stream endures from mid-October until late November, and used to be quite spectacular. Watch for the peak on November 17.

Tuesday, November 13 – Today is the birthday of James Clerk Maxwell. Born in 1831, Maxwell was a leading English theoretician on electromagnetism and the nature of light.

Tonight when you’ve explored the lunar surface on your own, let’s take a journey of 150 light-years as we honor Maxwell’s theories of electricity and magnetism as we take a look at a star that is in nuclear decay – Alpha Ceti.

Its name is Menkar, and this second magnitude orange giant is slowly using up its nuclear fuel and gaining mass. According to Maxwell’s theories of the electromagnetic and weak nuclear forces, W bosons must exist in such circumstances – this was an extremely advanced line of thinking for the time. Without getting deep into the physics, simply enjoy reddish Alpha for the beauty that it is. Even small telescopes will reveal its 5th magnitude optical partner 93 Ceti to the north. It’s only another 350 light-years further away! You’ll be glad you took the time to look this one up, because the wide separation and color contrast of the pair make this tribute to Maxwell worth your time!

Wednesday, November 14 – Up before dawn this morning? Take the time to look on the eastern horizon and see if you can still spot Mercury!

This evening on the Moon we will be returning to familiar features Theophilus, Cyrillus and Catharina. Why not take the time to really power up on them and look closely? Curving away just to the southwest of Catharina on the terminator is another lunar challenge feature, Rupes Altai, or the Altai Scarp. Look for smaller craters beginning to emerge, such as Kant to the northwest, Ibn-Rushd just northwest of Cyrillus and Tacitus to the west.

On this day in 1971, Mariner 9 became the first space probe to orbit Mars. Why not wait until the Red Planet rises above the atmosphere’s influence and have a look at it as well? Right now (and until the end of the year) is one of the best times to view Mars at a reasonable hour. Enjoy!

Thursday, November 15 – Today marks a very special birthday in history. On this day in 1738, my personal hero William Herschel was born. Among this British astronomer and musician’s many accomplishments, Herschel was credited with the discovery of the planet Uranus in 1781, the motion of the Sun in the Milky Way in 1785, Castor’s binary companion in 1804; and he was the first to record infrared radiation. Herschel was well known as the discoverer of many clusters, nebulae, and galaxies. This came through his countless nights studying the sky and writing catalogs whose information we still use today. Just look at how many we’ve logged this year! Tonight let’s look towards Cassiopeia as we remember this great astronomer…

Almost everyone is familiar with the legend of Cassiopeia and how the Queen came to be bound in her chair, destined for an eternity to turn over and over in the sky, but did you know that Cassiopeia holds a wealth of double stars and galactic clusters? Seasoned sky watchers have long been familiar with this constellation’s many delights, but let’s remember that not everyone knows them all, and tonight let’s begin our exploration of this Cassiopeia with two of its primary stars.

Looking much like a flattened “W,” its southern-most bright star is Alpha. Also known as Schedar, this magnitude 2.2 spectral type K star was once suspected of being a variable, but no changes have been detected in modern times. Binoculars will reveal its orange/yellow coloring, but a telescope is needed to bring out its unique features. In 1781, Herschel discovered a 9th magnitude companion star and our modern optics easily separate the blue/white component’s distance of 63″. A second, even fainter companion at 38″ is mentioned in the list of double stars and even a third at 14th magnitude was spotted by S.W. Burnham in 1889. All three stars are optical companions only, but make 150 to 200 light-year distant Schedar a delight to view!

Just north of Alpha is the next destination for tonight…Eta Cassiopeiae. Discovered by Herschel in August of 1779, Eta is quite possibly one of the most well-known of binary stars. The 3.5 magnitude primary star is a spectral type G, meaning it has a yellowish color much like our own Sun. It is about 10% larger than Sol and about 25% brighter. The 7.5 magnitude secondary (or B star) is very definitely a K-type: metal poor, and distinctively red. In comparison, it is half the mass of our Sun, crammed into about a quarter of its volume and is around 25 times dimmer. In the eyepiece, the B star will angle off to the northwest, providing a wonderful and colorful look at one of the season’s finest!

Friday, November 16 – Today in 1974, there was a party at Arecibo, Puerto Rico, as the new surface of the giant 1000-foot radio telescope was dedicated. At this time, a quick radio message was released in the direction of the globular cluster M13.

To give you a rough idea of how large craters really are on the Moon, take a look at Sacrobosco tonight – just west of the Theophilus, Cyrillus and Catharina trio. When you’ve located it, power up. As huge as the Arecibo dish looks, it would take 91 of them lined side by side to reach from edge to edge of Sacrobosco’s largest interior crater. Can you imagine the possibilities if we could use a lunar crater to house an even larger radio telescope?!

Now wait for the Moon to set, because the annual Leonid meteor shower is underway. For those of you seeking a definitive date and time, it isn’t always possible. The meteor shower itself belongs to the debris shed by comet 55/P Tempel-Tuttle as it passes our Sun in its 33.2 year orbital period. Although it was once assumed that we would merely add around 33 years to each observed “shower,” we later came to realize that the debris formed a cloud that lagged behind the comet and dispersed irregularly. With each successive pass of Tempel-Tuttle, new filaments of debris were left in space along with the old ones, creating different “streams” that the orbiting Earth passes through at varying times, which makes blanket predictions unreliable at best.

Saturday, November 17 – If you didn’t stay up late, then get up early this morning to catch the Leonids. Each year during November, we pass through the filaments of debris – both old and new – and the chances of impacting a particular stream from any one particular year of Tempel-Tuttle’s orbit becomes a matter of mathematical estimates. We know when it passed… We know where it passed… But will we encounter it and to what degree?

Traditional dates for the peak of the Leonid meteor shower occur as early as the morning of November 17 and as late as November 19, but what about this year? On November 8, 2005 the Earth passed through an ancient stream shed in 1001. Predictions ran high for viewers in Asia, but the actual event resulted in a dud. There is no doubt that we crossed through that stream, but its probability of dissipation is impossible to calculate. Debris trails left by the comet in 1333 and 1733 look the most promising for this year, but we simply don’t know.

We may never know precisely where and when the Leonids might strike, but we do know that a good time to look for this activity is well before dawn on November 17, 18 and 19th. With the Moon mostly out of the way, wait until the radiant constellation of Leo rises and the chances are good of spotting one of the offspring of periodic comet Tempel-Tuttle. Your chances increase significantly by traveling a dark sky location, but remember to dress warmly and provide for your viewing comfort.

On this day in 1970, the long running Soviet mission Luna 17 successfully landed on the Moon. Its Lunokhod 1 rover became the first wheeled vehicle on the Moon. Lunokhod was designed to function three lunar days but actually operated for eleven. The machinations of Lunokhod officially stopped on October 4, 1971, the anniversary of Sputnik 1. Lunokhod had traversed 10,540 meters, transmitted more than 20,000 television pictures, over 200 television panoramas and performed more than 500 lunar soil tests. We’ll take a look at its landing site in the days ahead. Spaseba!

Sunday, November 18 – If you got clouded out of the Leonids yesterday morning, there is no harm in trying again before dawn! The meteor stream varies, and your chances are still quite good of catching one of these bright meteors.

Tonight let’s head toward the lunar surface as we have a look at a series of lunar club challenges you may not have logged yet. Just slight below central towards lunar south, look for a series of rings which grow smaller as they progress. Once again, these are Ptolemaeus, Alphonsus and Arzachel. But, focus your attention on the largest of these, and in particular the small crater caught on its northern edge.

Named for Sir William himself, crater Herschel spans 41 kilometers wide and drops to a depth of 3770 kilometers below the surface. While you’re journeying, look for small Ammonius caught in Ptolemaeus’ interior. Further south, see if you can catch Alphonsus’ bright central peak. Ranger 9’s remains lay just northeast of there!

What’s Up this Week: November 5 – November 11, 2007

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Monday, November 5 – If you’re out looking for meteors this morning – and even if you’re not – take a look at the sweet pairing of the Moon and Venus. Take out a scope! Which has the larger crescent visible?

Today in 1906, a man named Fred Whipple was born. If that name doesn’t ring a bell for you – it should. Thanks to Dr. Whipple’s work we have a clearer understanding of the orbital mechanics of comets and their relation to meteoroid streams. Not only that, but he founded the SAO observatory in Arizona, discovered six comets, made invaluable contributions to research in the upper atmosphere, and was the first to call a comet a “dirty snowball.” His guess about the outgassing properties of comets was proved true when the first flyby of Comet Halley was made!

To honor Dr. Whipple a bit, let’s have a look at a beautiful optical pair/multiple system as we journey to the southernmost star in the “Circlet” – Kappa Piscium.

Easily split in even binoculars, this lovely green and violet combination of stars may have once belonged to the Pleiades group. 5th magnitude Kappa is a chromium star – one with unusual spectral iron properties – which rotates completely in around 48 hours. It shows lines of uranium, and the possibility of a very rare element known as holmium. Both the uranium and osmium content could be the result of a supernova explosion in a nearby star. Enjoy this colorful pair tonight!

Tuesday, November 6 – Tonight let’s head less than a degree south-southeast of Delta Ceti (RA 02 43 40.83 Dec -00 00 48.4) to have a look at a galaxy grouping that features the magnificent M77.

Discovered on October 29, 1780 by Pierre MÈchain, Messier cataloged it as #77 around six weeks later as a “nebulous cluster” – an accurate description for a small telescope. It wasn’t until 1850 when Lord Rosse uncovered its spiral nature that we began to view it as the grand structure seen in today’s modern telescopes.

Around 47 million light-years away, larger instruments will reveal its wide spiral arms where the older stars call home, and the concentrated core region where gigantic gas clouds move rapidly and new stars are being formed – a core which contains such a massive energy source that it emits spectrum of radio waves. After decades of study, the highly active nucleus of this Seyfert galaxy is known to have a mass equaling 10 million suns and a 5 light-year wide disc which rotates around it, which has intense star forming regions. This is one of the brightest known, and was cataloged by Arp as number 37 on his list of peculiar galaxies.

While even binoculars can spot the core, and modest scopes can reveal M77’s glory, larger telescopes will also spy 10th magnitude, edge-on NGC 1055 about half a degree north-northwest and 11th magnitude, face-on NGC 1073 about a degree north-northeast. Enjoy them tonight!

Wednesday, November 7 – Today in 1966, Lunar Orbiter 2 was launched. 30 years later on this same date, the Mars Global Surveyor left on its journey. Tonight let’s journey back to the area around M77 – because we’ve got more to explore!

Let’s start with Delta Ceti and head north about a degree for NGC 1032 (RA 02 39 23.74 Dec +01 05 37.7). Discovered in 1783 by Sir William Herschel and cataloged as H II.5, this 13th magnitude edge-on galaxy isn’t for the smaller scope, but that doesn’t mean it’s not interesting. Possessing a bright core region and an almost stellar nucleus, this superb galaxy was home to a supernova event in 2005!

Now, have a look at M77 again and head less than two degrees east for a pair of north/south oriented galaxies – NGC 1090 and NGC 1087 (RA 02 46 33.70 Dec -00 1 4 49.0). At around 120 million light-years away, northern NGC 1090 (H II.465) is also a supernova candidate, with events being reported in both 1962 and 1971. At close to magnitude 13, this barred spiral isn’t easy, but it can be spotted with aversion and a mid-sized telescope.

About 15′ south is NGC 1087. Although the pair seem quite close – no interaction between them has been detected. At magnitude 11, smaller scopes stand a much better chance a picking out 1087’s faint, round glow…while large scopes will get a sense of tightly wound spiral arms around Herschel II.466. Its barred structure is quite curious – far smaller than what is known to be common in this type of structure, but still a grand star forming region. A region that held a supernova event in 1995!

Check out this active group tonight…

Thursday, November 8 – Born on this day in 1656, the great Edmund Halley made his mark on history as he became best known for determining the orbital period of the comet which bears his name. English scientist Halley had many talents however, and in 1718 discovered that what were referred to as “fixed stars,” actually displayed proper motion! If it were not for Halley, Sir Isaac Newton may never have published his now famous work on the laws of gravity and motion. If Halley were alive today, you could bet that he’d have a big scope aimed about 4 degrees east of the Zeta and Chi pairing in Cetus to have a look at Hickson Compact Galaxy Group 16 (RA 02 09 31.71 Dec -10 08 59.7).

Consisting of four faint, small galaxies designated as NGC 835, NGC 833, NGC 838 and NGC 839 clustered around a 9th magnitude star, these aren’t for a small scope – but are a true challenge for a seasoned observer. Groups of galaxies such as Hickson 16 are believed to be some of the very oldest things in our Universe – and this particular one has a reputation of having an extremely large amount of starburst activity that is close enough for scientists to study. They were all cataloged by William Herschel in this month (on the 28th) in 1785. The northernmost, NGC 833, is known as HII.482, roughly magnitude 13, followed by NGC 835 (HII.483) which holds a magnitude 12. Next in line is NGC 838 (HII.484) at close to magnitude 13, followed southernmost by NGC 839 (HII.485) at magnitude 13. Not easy… But this beautiful crescent of four is worth the effort!

Friday, November 9 – Today is the birthdate of Carl Sagan. Born in 1934, Sagan was an American planetologist, exobiologist, popularizer of science and astronomy, and novelist. His influential work and enthusiasm inspired us all. If Carl were with us on this New Moon night, he would encourage amateurs of every level of astronomical ability! So let us embark to honor his memory with an optical pairing of stars known as Zeta and Chi Ceti, a little more than a fistwidth northeast of bright Beta. Now have a look with binoculars or small scopes because you’ll find that each has their own optical companion!

And northeast we continue with the largest of telescopes to investigate a galaxy cluster known as Abell 194 (RA 01 26 01.30 Dec -01 22 02.0). Over 100 galaxies have been found in this area and most of them are around 265 million light-years away. The brightest is NGC 547 and the pairing of NGC 547/545, which may be interacting with the elliptical NGC 541. Other viewable members include NGCs 548, 543, 535, 530, 519, 538, and 557, as well as far more southern 564, 560 and 558, just north of another optical double. No matter what you chose to look at tonight, as Dr. Sagan would say: “We are all star stuff.”

Saturday, November 10 – Tonight let’s have a look at one of the most elusive Messiers of all as we head about two fingerwidths northeast of Eta Pisces in search of M74 (RA 01 36.7 Dec +15 47).

Discovered at the end of September 1780 by MÈchain, M74 is a real challenge to smaller backyard telescopes – even at magnitude 9. This near perfect presentation of a face-on spiral galaxy has low surface brightness, and it takes really optimal conditions to spot much more than its central region. Located about 30 to 40 million light-years away, M74 is roughly the size as the Milky Way, yet contains no central bar. Its tightly wound spiral arms contain clusters of young blue stars and traces of nebulous star forming regions that can be seen in photos, yet little more than some vague concentrations in structure are all that can be noted visually even in a large scope. Yet, if sky conditions are great, even a small telescope can see details! Add the slightest bit of light pollution and even the biggest scopes will have problems locating it.

Don’t be disappointed if all you see is a bright nucleus surrounded by a small hazy glow – just try again another time. Who knows what might happen? A supernova was discovered in 2002 by a returning amateur and again in 2003 from the southern hemisphere. When it comes to M74, this is the very best time of year to try with a smaller scope!

Sunday, November 11 – Heads up! Tonight Antares will be within a half degree of the very young crescent Moon. For some observers, this could be an occultation, so be sure to check IOTA information.

A true observer was born on this day 1875. His name was Vesto Slipher, who spent some very quality time with the 60″ and 100″ telescopes on Mt. Wilson. Slipher was the first to photograph galaxy spectra and measure their redshifts, which led to the discovery of the expansion of the universe by Edwin Hubble.

On this night in 1572, the incomparable Tycho Brahe set out to record a bright new star. Today we realize he was looking at a supernova! “Visible” now as a supernova remnant only at very long wavelengths in the constellation of Cassiopeia, if you are good with your finderscope, you can still view it as a 7th magnitude star. Using Gamma, Alpha and Beta as your visual starting point, use binoculars to locate Kappa just north of this trio. Small Kappa will also be part of a configuration of stars which will look much like our starting point, only much dimmer. From Kappa, you will see a line of stars heading northwest. The very first in this series of 7th magnitude stars is SN 1572 (RA 00 25 08.07 Dec +64 09 55.7). According to Tycho’s report from Burnham’s Celestial Handbook:

“On the 11th day of November in the evening after sunset, I was contemplating the stars in a clear sky. I noticed that a new and unusual star, surpassing the other stars in brilliancy, was shining almost directly above my head; and since I had, from boyhood, known all the stars of the heavens perfectly, it was quite evident to me that there had never been any star in that place of the sky, even the smallest, to say nothing of a star so conspicuous and bright as this. I was so astonished of this sight that I was not ashamed to doubt the trustworthyness of my own eyes. But when I observed that others, on having the place pointed out to them, could see that there was really a star there, I had no further doubts. A miracle indeed, one that has never been previously seen before our time, in any age since the beginning of the world.”

So bright was the event, that it rivaled Jupiter at the time and soon surpassed Venus – being visible during the day for nearly two weeks. It had faded by the end of November, slowly changing color to red when it passed away from strong visibility almost 16 months later. We’ll be forever glad it wasn’t cloudy at the time, for the event inspired Tycho Brahe to dedicate his life to astronomy… And who’d blame him?!

What’s Up this Week: October 29 – November 4, 2007

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Monday, October 29 – On this night in 1749, the French astronomer Le Gentil was at the eyepiece of an 18′ focal length telescope. His object of choice was the Andromeda Galaxy, which he believed to be a nebula. Little did he know at the time that his descriptive notes also included M32, a satellite galaxy of M31. It was the first small galaxy discovered, and it would be another 175 years before these were recognized as such by Edwin Hubble.

Tonight, take the time to view the Andromeda Galaxy for yourself. Located just about a degree west of Nu Andromeda, this ghost set against the starry night was known as far back as 905 AD, and was referred to as the “Little Cloud.” Located about 2.2 million light-years from our solar system, this expansive member of our Local Galaxy Group has delighted observers of all ages throughout the years. No matter if you view with just your eyes, a pair of binoculars or a large telescope, M31 still remains one of the most spectacular galaxies in the night.

“Boo” tiful…

Tuesday, October 30 – Today in 1981 Venera 13 was launched on its way toward Venus – did you catch the bright planet before dawn?

What Halloween celebration would be complete without a black cat? Tonight let’s cruise Draco “The Dragon” in search of the “Cat’s Eye”…

Located about halfway between Delta and Zeta Draconis is one of the brightest planetary nebulae in the night – 8.8 magnitude NGC 6543. Around three thousand light-years away, it was one of the first planetary nebulae to be studied spectroscopically and the resulting emission lines proved that the phenomenon was actually a shell of gas emitted from a dying star – a fate that awaits our own Sun.

While a small telescope will never reveal NGC 6543 as gloriously as a Hubble image, you can expect even in a small telescope or binoculars to make out a small, blue/green glowing object. Large aperture telescopes and good sky conditions are needed to reveal some of the braided structure seen within this bright object. No matter how you view it, the “Cat’s Eye” belongs on the list of spooky objects!

Wednesday, October 31 – Happy Halloween! Many cultures around the world celebrate this day with a custom known as “Trick or Treat.” Tonight instead of tricking your little ghouls and goblins, why not treat them to a sweet view through your telescope or binoculars?

So far we’ve collected a demon, a pumpkin, a galactic ghost, and the eye of the cat… And what Halloween would be complete without a witch! Easily found from a modestly dark site with the unaided eye, the Pleiades can be spotted well above the northeastern horizon within a couple of hours of nightfall. To average skies, many of the 7 bright components will resolve easily without the use of optical aid, but to telescopes and binoculars? M45 is stunning…

First let’s explore a bit of history. The recognition of the Pleiades dates back to antiquity and its stars are known by many names in many cultures. The Greeks and Romans referred to them as the “Starry Seven,” the “Net of Stars,” “The Seven Virgins,” “The Daughters of Pleione,” and even “The Children of Atlas.” The Egyptians referred to them as “The Stars of Athyr,” the Germans as “Siebengestiren” (the Seven Stars), the Russians as “Baba” after Baba Yaga, the witch who flew through the skies on her fiery broom. The Japanese call them “Subaru,” Norsemen saw them as packs of dogs and the Tonganese as “Matarii” (the Little Eyes). American Indians viewed the Pleiades as seven maidens placed high upon a tower to protect them from the claws of giant bears, and even Tolkien immortalized the stargroup in “The Hobbit” as “Remmirath.” The Pleiades have even been mentioned in the Bible! So, you see, no matter where we look in our “starry” history, this cluster of seven bright stars has been part of it. But, let’s have some Halloween fun!

The date of the Pleiades culmination (its highest point in the sky) has been celebrated through its rich history by being marked with various festivals and ancient rites – but there is one particular rite that really fits this occasion! What could be more spooky on this date than to imagine a group of Druids celebrating the Pleiades’ midnight “high” with Black Sabbath? This night of “unholy revelry” is still observed in the modern world as “All Hallow’s Eve” or more commonly as Halloween. Although the actual date of the Pleiades midnight culmination is now on November 21 instead of October 31, why break with tradition? Thanks to its nebulous regions, M45 looks wonderfully like a “ghost” haunting the starry skies.

Treat yourself and your loved ones to the “scariest” object in the night. Binoculars give an incredible view of the entire region, revealing far more stars than are visible with the naked eye. Small telescopes at lowest power will enjoy M45’s rich, icy-blue stars and fog-like nebulosity. Larger telescopes and higher power reveal many pairs of double stars buried within its silver folds. No matter what you choose, the Pleiades definitely rock!

Thursday, November 1 – On this day in 1977, Charles Kowal made a wild discovery – Chiron. This represented the first discovery of a multitude of tiny, icy bodies that lie in the outer reaches of our solar system. Collectively known as Centaurs, they reside in unstable orbits between Jupiter and Neptune and are almost certainly “refugees”” from the Kuiper Belt

Tonight let’s go for something small, but white-hot as we head for a dwarf star and planetary nebula, NGC 246. You’ll find it just a bit more than a fistwidth north-northeast of Beta Ceti (RA 00 47 03.34 Dec -11 52 18.9).

First discovered by Sir William Herschel and cataloged as object V.25, this 8th magnitude planetary nebula has a wonderful patchy, diffuse structure that envelops four stars. Around 1600 light-years away, the nebulosity you can see around the exterior edges was once the outer atmosphere of a star much like our own Sun. At the center of the nebula lies the responsible star – the fainter member of a binary system. While it is now in the process of becoming a white dwarf, we can still enjoy the product of this expanding shell of gas that is often called the “Skull Nebula.”

Friday, November 2 – Today celebrates the birth of an astronomy legend – Harlow Shapely. Born in 1885, the American-born Shapley paved the way in determining distances to stars, clusters, and the center of our Milky Way galaxy. Among his many achievements, Shapely was also the Harvard College Observatory director for many years. Today in 1917 also represents the night first light was seen through the Mt. Wilson 100″ telescope.

Of course, Dr. Shapley spent his fair share of time on the Hooker telescope as well. One of his many points of study was globular clusters, their distance, and their relationship to the halo structure of our galaxy. Tonight let’s have a look at a very unusual little globular located about a fistwidth south-southeast of Beta Ceti and just a couple of degrees north-northwest of Alpha Sculptor (RA 00:52:47.5 Dec -26:35:24), as we have a look at NGC 288.

Discovered by William Herschel on October 27, 1785, and cataloged by him as H VI.20, the class X globular cluster blew apart scientific thinking in the late 1980’s as a study of perimeter globulars showed it to be more than 3 million years older than similar globulars – thanks to the color magnitude diagrams of Hertzsprung and Russell. By identifying both its blue and red branches, it was shown that many of NGC 288’s stars are being stripped away by tidal forces and contributing to the formation of the Milky Way’s halo structure. In 1997, three additional variable stars were discovered in this cluster.
At magnitude 8, this small globular is easy for southern observers, but faint for northern ones. If you are using binoculars, be sure to look for the equally bright spiral galaxy NGC 253 to the globular’s north.

Saturday, November 3 – On this day in 1955, one of the few documented cases of a person being hit by a meteorite occurred. What are the odds on that?

1957 the Russian space program launched its first “live” astronaut into space – Laika. Carried on board Sputnik 2, our canine hero was the first living creature to reach orbit. The speedily developed Sputnik 2 was designed with sensors to transmit the ambient pressure, breathing patterns and heartbeat of its passenger, and also had a television camera on board to monitor its occupant. The craft also studied ultraviolet and x-ray radiation to further assess the impact of space flight upon live occupants. Unfortunately, the technology of the time offered no way to return Laika to Earth, so she perished in space. On April 14, 1958, Laika and Sputnik 2 returned to Earth in a fiery re-entry after 2,570 orbits.

Since we’ve got the scope out, let’s go have another look at that galaxy we spied last night!

Discovered by Caroline Herschel on September 23, 1783, NGC 253 (RA 00 47.6 Dec -25 17) is the brightest member of a concentration of galaxies known as the Sculptor Group, near to our own local group and the brightest of all outside it. Cataloged as both H V.1 and Bennett 4, this 7th magnitude beauty is also known as Caldwell 65, and due to both its brightness and oblique angle is often called the “Silver Dollar Galaxy.” As part of the SAC 110 best NGCs, you can even spot this one if you don’t live in the Southern Hemisphere. At around 10 million light-years away, this very dusty, star-forming Seyfert galaxy rocks in even a modest telescope!

Sunday, November 4 – This morning will be the peak of the Southern Taurid meteor shower. Already making headlines around the world for producing fireballs, the Taurids will be best visible in the early morning hours as soon as the Moon is far west.. The radiant for this shower is, of course, the constellation of Taurus and red giant Aldeberan, but did you know the Taurids are divided into two streams?

It is surmised that the original parent comet shattered as it passed our Sun around 20,000 to 30,000 years ago. The larger “chunk” continued orbiting and is known as periodic comet Encke. The remaining debris field turned into smaller asteroids, meteors and larger fragments that often pass through our atmosphere creating the astounding “fireballs” known as bolides. Although the fall rate for this particular shower is rather low at 7 per hour, these slow traveling meteors (27 km or 17 miles per second) are usually very bright and appear to almost “trundle” across the sky. With the chances high all week of seeing a bolide, this makes a bit of quiet contemplation under the stars worthy of a morning walk. Be sure to look at how close Saturn is to the Moon!

For unaided eye or binocular observers – or those who just wish something a bit “different” tonight – have a look at 19 Pisces. You’ll find it as the easternmost star in the small “circlet” just south of the Great Square of Pegasus.

Also known as TX, you’ll find this one quite delightful for its strong red color. TX is a cool giant star which varies slightly in magnitude on an irregular basis. This carbon star is located anywhere from 400 to 1000 light-years away and rivals even R Leporis’ crimson beauty.

What’s Up this Week: October 22 – October 28, 2007

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Monday, October 22 – Something very special happened today in 2136 B.C. There was a solar eclipse, and for the very first time it was seen and recorded by Chinese astronomers. And probably a very good thing because in those days the royal astronomers were executed for failure to predict!Today is also the birthday of Karl Jansky. Born in 1905, Jansky was an American physicist as well as an electrical engineer. One of his pioneer discoveries was non-Earth-based radio waves at 20.5 MHz, a detection he made while investigating noise sources during 1931 and 1932. And, in 1975, Soviet Venera 9 was busy sending Earth the very first look at Venus’ surface. If you are up before dawn this morning, why not take a moment to have a look at Venus yourself. Can you tell what phase it is in through the telescope?

Also today in 1966 Luna 12 was launched towards the Moon – as so shall we be. Tonight we’ll let Gassendi be our guide as we head north to examine the ruins of crater Letronne. Sitting on a broad peninsula on the south edge of Oceanus Procellarum, this class V crater once spanned 118 kilometers. Thanks to the lava flows which formed Procellarum, virtually the entire northern third of the crater was submerged beneath the flow, leaving the remaining scant walls to rise no more than a thousand meters above the surface. While that might seem shallow, that’s as high as El Capitan in Yosemite!

Tuesday, October 23 – Tonight the Moon itself will be our starting point as we look for the planet Uranus less than 2 degrees south. Fix its position in your memory, because it will play a role in just 24 hours.

If you journey to the Moon tonight, you might return to the southern quadrant along the terminator to have a look at 227 kilometer diameter crater Schickard. Seen on the oblique, this great crater’s floor is so humped in the middle that you could stand there and not see the crater walls! Be sure to note Schickard for your lunar challenge studies.

After having looked at the Moon, take the time out to view a bright southern star – Fomalhaut. Also known as “The Lonely One,” Alpha Piscis Austrini seems to sit in a rather empty area in the southern skies, some 23 light-years away. At magnitude 1, this main sequence A3 giant is the southern-most visible star of its type for northern hemisphere viewers, and it is the 18th brightest star in the sky. “The Lonely One” is about twice the diameter of our own Sun, but 14 times more luminous! Just a little visual aid is all that it takes to reveal its optical companion…

Wednesday, October 24 – Today in 1851, a busy astronomer was at the eyepiece as William Lassell discovered Uranus’ moons Ariel and Umbriel. Although this is far beyond backyard equipment, we can have a look at that distant world, as we find Uranus just where we left it last night – only a bit further away from the Moon’s influence.

While Uranus’ small, blue/green disc isn’t exactly the most exciting thing to see in a small telescope or binoculars, the very thought that we are looking at a planet that’s over 18 times further from the Sun than we are is pretty impressive! Usually holding close to a magnitude 6, we watch as the tilted planet orbits our nearest star once every 84 years. Its atmosphere is composed of hydrogen, helium and methane, yet pressure causes about a third of this distant planet to behave as a liquid. Larger telescopes may be able to discern a few of Uranus’ moons, for Titania (the brightest) is around magnitude 14.

Thursday, October 25 – And who was watching the planets in 1671? None other than Giovanni Cassini – because he’d just discovered Saturn’s moon Iapetus. If you’re up before dawn this morning, have a look at Saturn for yourself. Iapetus usually holds around a magnitude of 12, and orbits well outside of bright Titan’s path.

Today is the birthday of Henry Norris Russell. Born in 1877, Russell was the American leader in establishing the modern field of astrophysics. As the namesake for the American Astronomical Society’s highest award (for lifetime contributions to the field), Mr. Russell is the “R” in HR diagrams, along with Mr. Hertzsprung. This work was first used in a 1914 paper, published by Russell.

Tonight let’s have a look at a star that resides right in the middle of the HR diagram as we have a look Beta Aquarii.

Named Sadal Suud (“Luck of Lucks”), this star of spectral type G is around 1030 light-years distant from our solar system and shines 5800 times brighter than our own Sun. The main sequence beauty also has two 11th magnitude optical companions. The one closest to Sadal Suud was discovered by John Herschel in 1828, while the further star was reported by S.W. Burnham in 1879.

Friday, October 26 – It’s big. It’s bright. It’s the Full Moon just before Halloween! For the next five days, let’s take a look at some of the “spookiest” objects in the night sky…

This evening we are once again going to study a single star, which will help you become acquainted with the constellation of Perseus. Its formal name is Beta Persei and it is the most famous of all eclipsing variable stars. Tonight, let’s identify Algol and learn all about the “Demon Star.”

Ancient history has given this star many names. Associated with the mythological figure Perseus, Beta was considered to be the head of Medusa the Gorgon, and was known to the Hebrews as Rosh ha Satan or “Satan’s Head.” 17th century maps labeled Beta as Caput Larvae, or the “Specter’s Head,” but it is from the Arabic culture that the star was formally named. They knew it as Al Ra’s al Ghul, or the “Demon’s Head,” and we know it as Algol. Because these medieval astronomers and astrologers associated Algol with danger and misfortune, we are led to believe that Beta’s strange visual variable properties were noted throughout history.

Italian astronomer Geminiano Montanari was the first to record that Algol occasionally “faded,” and its methodical timing was cataloged by John Goodricke in 1782, who surmised that it was being partially eclipsed by a dark companion orbiting it. Thus was born the theory of the “eclipsing binary” and this was proved spectroscopically in 1889 by H. C. Vogel. At 93 light-years away, Algol is the nearest eclipsing binary of its kind, and is treasured by the amateur astronomer because it requires no special equipment to easily follow its stages. Normally Beta Persei holds a magnitude of 2.1, but approximately every three days it dims to magnitude 3.4 and gradually brightens again. The entire eclipse only lasts about 10 hours!

Although Algol is known to have two additional spectroscopic companions, the true beauty of watching this variable star is not telescopic – but visual. The constellation of Perseus is well placed this month for most observers and appears like a glittering chain of stars that lie between Cassiopeia and Andromeda. To help further assist you, re-locate last week’s study star, Gamma Andromedae (Almach) east of Algol. Almach’s visual brightness is about the same as Algol’s at maximum.

Saturday, October 27 – Now we need a jack-o-lantern…

Asteroid Vesta is considered to be a minor planet since its approximate diameter is 525 km (326 miles), making it slightly smaller in size than the state of Arizona. Vesta was discovered on March 29, 1807 by Heinrich Olbers and it was the fourth such “minor planet” to be identified. Olbers’ discovery was fairly easy because Vesta is the only asteroid bright enough at times to be seen unaided from Earth. Why? Orbiting the Sun every 3.6 years and rotating on its axis in 5.24 hours, Vesta has an albedo (or surface reflectivity) of 42%. Although it is about 220 million miles away, pumpkin-shaped Vesta is the brightest asteroid in our solar system because it has a unique geological surface. Spectroscopic studies show it to be basaltic, which means lava once flowed on the surface. (Very interesting, since most asteroids were once thought to be rocky fragments left-over from our forming solar system!)

Studies by the Hubble telescope have confirmed this, as well as shown a large meteoric impact crater which exposed Vesta’s olivine mantle. Debris from Vesta’s collision then set sail away from the parent asteroid. Some of the debris remained within the asteroid belt near Vesta to become asteroids themselves with the same spectral pyroxene signature, but some escaped through the “Kirkwood Gap” created by Jupiter’s gravitational pull. This allowed these small fragments to be kicked into an orbit that would eventually bring them “down to Earth.” Did one make it? Of course! In 1960 a piece of Vesta fell to Earth and was recovered in Australia. Thanks to Vesta’s unique properties, the meteorite was definitely classified as once being a part of our third largest asteroid. Now, that we’ve learned about Vesta, let’s talk about what we can see from our own backyards.

As you can discern from the image, even the Hubble Space Telescope doesn’t give incredible views of this bright asteroid. What we will be able to see in our telescopes and binoculars will closely resemble a roughly magnitude 7 “star,” and it is for that reason that I strongly encourage you to visit Heavens Above, follow the instructions and print yourself a detailed map of the area. When you locate the proper stars and the asteroid’s probable location, mark physically on the map Vesta’s position. Keeping the same map, return to the area a night or two later and see how Vesta has moved since your original mark. Since Vesta will stay located in the same area for awhile, your observations need not be on a particular night, but once you learn how to observe an asteroid and watch it move – you’ll be back for more!

Sunday, October 28 – Today in 1971, Great Britain launched its first satellite – Prospero.

One of the scariest movies in a long time was the “Ring”… Let’s find one! Tonight’s dark sky object is a difficult one for northern observers and is truly a challenge. Around a handspan south of Zeta Aquarii and just a bit west of finderscope star Upsilon is a remarkably large area of nebulosity that is very well suited to large binoculars, rich field telescopes and wide field eyepieces. Are you ready to walk into the “Helix?”

Known as NGC 7293, this faint planetary nebula “ring” structure is around half the size of the full Moon. While its total magnitude of 6.5 and large size should indicate an easy find, the “Helix” is anything but easy because of its low surface brightness. Binoculars will show it as a large, round, hazy spot while small telescopes with good seeing conditions will have a chance to outshine larger ones by using lower power eyepieces to pick up the braided ring structure.

As one of the very closest of planetary nebulae, NGC 7393 is very similar in structure to the more famous Ring – M57. It is a spherical shell of gas lighted by an extremely hot, tiny central star that’s only around 2% of our own Sun’s diameter – yet exceeds Sol in surface temperature by over 100,000 Kelvin. Can you resolve it? Best of luck!

What’s Up this Week: October 15 – October 21, 2007

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Monday, October 15 – As the evening begins, be sure to at least walk out and look at the Moon. For many observers, bright red Antares will be only around a half degree north of the waxing crescent. Of course, you know that a brush this close could mean an occultation for your area! Be sure to check IOTA for visibility locations and times. No special equipment is needed to check out a lunar occultation, but thanks to an historic observation of just such an event, Antares’ companion star was discovered by Professor Johannes Burg in Vienna on April 13, 1819!

Today in 1963 marks the first detection of an interstellar molecule. This discovery was made by Sander Weinreb (with Barrett, Meeks, and Henry) on the MIT Millstone Hill 84-foot dish. The discovery was made possible by new correlation receiver technology, and picked up a hydroxyl molecule in an absorption band. By using the radio galaxy Cas A as a background continuum source, the detection occurred at 1667.46 MHz and again at 1665.34 MHz. By the dawn of 2000, nearly 200 different interstellar molecules had been identified and many of these are classified as organic.

Tonight let’s have a look at a radio source as we visit a pulsar located almost mid-way between Theta and Beta Capricorni – PSR2045+16.

While pulsars aren’t truly visible objects, there is still something undeniably cool about locating the field in which a rotating neutron star is sending out staccato pulses of radio waves anywhere between .001 and 4 seconds apart. If you have bright star 19 in the binocular field, then you know you’re in the right area for many radio sources, including many nearby quasars… Just imagine the possibilities!

Tuesday, October 16 – Do you remember Professor Burg who discovered Antares’ companion during an occultation? Then tonight let’s have a look at the crater named for him as we begin by using past study crater Posidonius as our guide.

If you walk along the terminator to the northwest, you’ll see the punctuation of 40 kilometer-wide Burg just emerging from the shadows. While it doesn’t appear to be a grand crater like Posidonius, it has a redeeming feature: it’s deep – real deep. If Burg were filled with water here on Earth, it would require a deep submergence vehicle like ALVIN to reach its 3680 meter floor! This class II crater stands fairly alone on an expanse of lunarscape known as Lacus Mortis. If the terminator has advanced enough at your time of viewing, you may be able to see this walled plain’s western boundary peeking out of the shadows.

Now let’s drop south-southeast of Beta Capricorni to have a look at a pair of doubles – Rho and Pi.

Northernmost Pi is a multiple system slightly less than 100 light-years away, with each discernable member also being a spectroscopic double. Separated by about an eighth of a light-year, look for a 5th magnitude yellow/white giant with a very close 9th magnitude companion. Further south is Pi, a triple star system which has a traditional name – Okul. Located around 670 light-years away, look for a bright blue/white 5th magnitude primary that is also a spectroscopic double – and its much easier C component, which is around magnitude 8.

Wednesday, October 17 – Tonight let’s start with the Moon and explore a binocular curiosity.

Look on the northeast shore of Mare Serenitatis for the bright ring of Posidonius, which contains several equally bright points both around and within it. Now look at Mare Crisium and get a feel for its size. A little more than one Crisium’s length west of Posidonius you’ll meet Aristotle and Eudoxus. Drop a similar length south and you will be at the tiny, bright crater Linne on the expanse of Mare Serenitatis. So what’s so cool about this little white dot? With only binoculars you are resolving a crater that is one mile wide, in a seven mile wide patch of bright ejecta from close to a quarter of a million miles away!

Now point those binoculars towards the northwestern corner of Capricornus and have a look a spectacular Alpha!

Although the Alpha 1 and 2 pairing is strictly a visual binary, that won’t stop you from enjoying their slightly yellow and orange colors. Collectively they are named Al Giedi, and the brighter of the pair is Alpha 2 at about 100 light-years distant; while Alpha 1 is around five times further away. Now power up with a telescope and you’ll find that both stars are also visual doubles! While the companion stars to both are around the same magnitude, you’ll find that Alpha 2 is separated by three times as much distance. Be sure to mark your observation lists and enjoy!

Thursday, October 18 – Today in 1959, Soviet Luna 3 began returning the first photographs of the Moon’s far side. Also today – but in 1967 – the Soviets again made history as Venera 4 became the first spacecraft to probe Venus’ atmosphere. If you’re up before dawn, be sure to have a look at brilliant Venus pairing with the solemn Saturn. You’ll find them just a few fingerwidths apart!

Tonight let’s walk on the Moon and check off a few more features on your lunar list! Look for the prominent pair of Aristillus and Autolycus caught just east of the Apennine Mountain range. If you haven’t logged the shallow Archimedes, tonight is your chance. Take the time to closely inspect the differing lava flow patterns on the floor of Palus Putredinus – and you can’t miss the bright ring of Manilius!

When we’re done? Let’s go have a look at Gamma Aquilae just for the heck of it. Just northwest of bright Altair, Gamma has the very cool name of Tarazed and is believed to be over 300 light-years away. This K3 type giant will show just a slightly yellow coloration – but what really makes this one special is the low power field!

Friday, October 19 – Our lunar mission for tonight is to move south past the crater rings of Ptolemaeus, Alphonsus, Arzachel and Purbach until we end up at the spectacular crater Walter. Named for Dutch astronomer Bernhard Walter, this 132 by 140 kilometer-wide lunar feature offers up amazing details at high power. Perhaps amongst the most fascinating is to take the time to study the differing levels, which drop to a maximum of 4130 meters below the surface. Multiple interior strikes abound, but the most fascinating of all is the wall crater Nonius. Spanning 70 kilometers, Nonius would also appear to have a double strike of its own – one that’s 2990 meters deep!

Now, let’s go have a look at the northeastern corner of Capricornus as we learn about Delta…

Its proper name is Deneb Algedi and this nearly 3rd magnitude star is a stunning blue/ white. Curiously enough, it’s a rather close star – only about 50 light-years from Earth. Hovering so close to it that we cannot even correctly assess its spectral type is a binary companion whose eclipsing orbit causes Delta to be a very slight variable – with a period of just about one day. In its own way, Delta is rather historic… For it was only 4 degrees north of this star that Uranus was first sighted by Galle in 1846!

Saturday, October 20 – It’s bold. It’s beautiful. You’ve looked at it hundreds of times…and tonight? It’s Copernicus…

While Copernicus is not the oldest, deepest, largest, or brightest crater on the Moon, it certainly is one of the most detailed. Visible in binoculars toward Plato and near the terminator, this youthful crater gives a highly etched appearance. Its location in a fairly smooth plain near the center of the Moon’s disc, and its prominent “splash” ray system, all combine to make Copernicus visually stunning in a small telescope.

Spanning 100 kilometers in diameter, with 23 kilometer thick walls, the “Mighty One” is most definitely an impact crater that left its impression down to 3840 meters below the surface. Geologist Gene Shoemaker cited many features of Copernicus which mirror our own terrestrial impact features. Many of these Copernican features could have been caused by a large meteoritic body…a body about the size of Comet Halley’s nucleus. No matter what optical aid you use, mid-placed Copernicus simply rocks!

Now we are slipping into the stream of Comet Halley and into one of the finest meteor showers of the year. If skies are clear tonight, this would be the perfect chance to begin your observations of the Orionid meteor shower. But go to bed early… And wait for the Moon to set!

Sunday, October 21 – Be sure to be outdoors before dawn to enjoy one of the year’s most reliable meteor showers. The offspring of Comet Halley will grace the early morning hours as they return once again as the Orionid meteor shower. This dependable shower produces an average of 10-20 meteors per hour at maximum and the best activity begins before local midnight on the 20th, and reaches its best as Orion stands high to the south at about two hours before local dawn on the 21st. With the Moon nearly out of the picture, this is gonna be great!

Although Comet Halley has long since departed our Solar System, the debris left from its trail still remain scattered in Earth’s orbital path around the Sun, allowing us to predict when this meteor shower will occur. We first enter the “stream” at the beginning of October and do not leave it until the beginning of November, making your chances of “catching a falling star” even greater! These meteors are very fast, and although they are faint, it is still possible to see an occasional fireball that leaves a persistent trail.

For best success, try to get away from city lights. Facing south-southeast, simply relax and enjoy the stars of the winter Milky Way. The radiant, or apparent point of origin, for this shower will be near the red giant Alpha Orionis (Betelguese), but meteors may occur from any point in the sky. You will make your meteor watching experience much more comfortable if you take along a lawn chair, a blanket and a thermos of your favorite beverage.

Clouded out? Don’t despair. You don’t always need your eyes or perfect weather to meteor watch. By tuning an FM radio to the lowest frequency possible that does not receive a clear signal, you can practice radio meteor listening! An outdoor FM antenna pointed at the zenith and connected to your receiver will increase your chances, but it’s not necessary. Simply turn up the static and listen. Those hums, whistles, beeps, bongs, and occasional snatches of signals are our own radio signals being reflected off the meteor’s ion trail!

Pretty cool, huh?

What’s Up this Week: October 8 – October 14, 2007

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Monday, October 8 – Today marks the birthday of Ejnar Hertzsprung. Born 1873, Hertzsprung was a Danish astronomer who first proved the existence of giant and dwarf stars in the early 1900s. His discoveries included the relationship between color and luminosity, which wasn’t truly recognized until it was recovered by Henry Russell. Now it is a familiar part of all our studies as the Hertzsprung-Russell diagram. His use of absolute magnitudes will come into play tonight as we have a look at the age-old mystery of M73.

Located about three fingerwidths north-northwest of Theta Capricorni (RA 58.9 Dec -12 38), this 9th magnitude open cluster consisting of four stars was discovered by Charles Messier on October 4, 1780. He described it as a “Cluster of three or four small stars, which resembles a nebula at first glance…” Hotly debated as to whether or not the grouping is a genuine cluster or simply an asterism, it was also included in J. Herschel’s catalog (GC 4617) and given the NGC 6994 designation by Dreyer. In 1931 Collinder cataloged M73 as Cr 426, with an estimated distance of 12,000 light-years. Still, the debate about its authenticity as a physically related group continued.

At least two stars show the same proper motion, leading scientists to believe M73 may be the remnant of a much older and now dispersed cluster – or simply two related stars. Of the 140 stars investigated in the region, 24 may be real members, including those in Messier’s original observation. Thanks to the work of Hertzsprung and Russell, these candidates fall within the color-magnitude diagram of a 2 to 3 billion year old cluster with Messier’s suspect four being evolved giants.

The most recent data indicates M73 may simply be an asterism – sharing no common proper motion, but until more studies are undertaken you can enjoy this unusual Messier in even a small telescope!

Tuesday, October 9 – Tonight is the peak of the Draconid meteor shower whose radiant is near the westering constellation of Hercules. This particular shower can be quite impressive when comet Giacobini-Zinner passes near Earth. When this happens, the fall rate jumps to 200 per hour and has even been known to reach 1000. So what am I going to tell you about this year? Comet Giacobini-Zinner reached perihelion on July 2nd of 2005, passing with 8 million kilometers of Earth, but has now greatly distanced itself from our solar system. Chances are the Draconids will only produce around 3 to 5 per hour, but no one knows for sure!

While we’re out, let’s take the time to have a peek at M72, just about a degree and a half west (RA 20 53.5 Dec -12 32) of last night’s target M73.

Originally found by Méchain on the night of August 29-30, 1780, this class IX globular cluster is one of the faintest and most remote of the Messiers, and Charles didn’t catalog it until over a month after its discovery. At around magnitude 9, this 53,000 light-year distant globular will be not much more than a faint round smudge in smaller aperture, but will take on a modicum of resolution in larger telescopes. Well beyond the galactic center and heading toward us at 255 kilometers per second, M72 is home to 42 variables and the average magnitude of its members is around 15. While mid-sized scopes will pick up a graininess in the texture of this globular, notice how evenly the light is distributed, with little evidence of a core region. Be sure to write down your observations!

Wednesday, October 10 – Today in 1846, William Lassell was busy at his scope as he made a new discovery – Neptune’s moon Triton! Although our everyday equipment can’t “see” Triton, we can still have a look at Neptune which is also hanging out in tonight’s study constellation of Capricornus. Try checking astronomy periodicals or many great on-line sites for accurate locator charts.

Tonight let’s head to the eastern portion of Capricornus and start by identifying Zeta about a fistwidth southwest of the eastern corner star – Delta. Now look southeast about 2 fingerwidths and identify 5th magnitude star 41. About one half degree west is our target globular for the evening, M30.

At near magnitude 8, this class V globular cluster is well suited to even binoculars and becomes spectacular in a telescope. Originally discovered by Messier in August 1764 and resolved by William Herschel in 1783, some of M30’s most attractive features are the branches of stars which seem to radiate from its concentrated core region. Estimated to be around 26,000 light-years away, you’ll find it fairly well resolved in large aperture, but take time to really look. The dense central region may have already undergone core collapse – yet as close as these stars are, very few have collided to form x-ray binaries. For the smaller scope, notice how well M30’s red giants resolve and be sure to mark your notes!

Thursday, October 11 – Tonight is officially New Moon and time for a telescopic challenge – a compact galaxy group. You’ll find it less than half a degree southeast of stellar pair 4 and 5 Aquarii (RA 20 52 26.00 Dec -05 46 19.1).

Known as Hickson 88, this grouping of four faint spiral galaxies is estimated to be around 240 million light-years away and is by no means an easy object – yet the galactic cores can just be glimpsed with mid-sized scopes from a very dark site. Requiring around 12.5″ to study, you’ll find the brightest of these to be northernmost NGC 6978 and NGC 6977. While little detail can be seen in the average large backyard scope, NGC 6978 shows some evidence of being a barred spiral, while NGC 6977 shows the even appearance of a face-on. Further south, NGC 6976 is much smaller and considerably fainter. It is usually caught while averting and studying the neighborhood. The southernmost galaxy is NGC 6975, whose slender, edge-on appearance makes it much harder to catch.

Although these four galaxies seem to be in close proximity to one another, no current data suggests any interaction between them. While such a faint galaxy grouping is not for everyone, it’s a challenge worthy of seasoned astronomer with a large scope! Enjoy…

Friday, October 12 – Today in 1891, the Astronomical Society of France was established. Exactly one year later in 1892, astronomy great E. E. Barnard was hard at work using the new tool of photography and became the first to discover a comet – 1892 V – in this way!

Not only did Barnard use photography for comets, but his main interest of study was details within the Milky Way. Tonight let us take out binoculars or a telescope at the widest possible field of view and have a look at two such regions in the westering Aquila – The “Double Dark Nebula.”

Just northeast of Altair is bright star Gamma Aquilae, and about a fingerwidth west is a pair of Barnard discoveries: B142 and B143 – two glorious absences of stars known as interstellar dust clouds. B143 is no more than a half degree in size and will simply look like a blank area shaped like a horseshoe, with its extensions point toward the west. Just south is B142, an elongated comma shape, which seems to underline its companion.

Located anywhere from 1000 to 3000 light-years away, these non-luminous clouds of gas and dust are a very fine example of Barnard’s passion. Do not be upset if you don’t see them on your first attempt – for the chances are if you are seeing “nothing,” you are looking in the right place!

Saturday, October 13 – Today marks the founding of the British Interplanetary Society in 1933. “From imagination to reality,” the BIS is the world’s oldest established organization devoted solely to supporting and promoting the exploration of space and astronautics.

Tonight we’ll do them proud as we have a look at the mighty M2. You’ll find it located about three fingerwidths north-northeast of Beta Aquarii (RA 33.5 Dec 00 49).

At slightly dimmer than 6th magnitude, this outstanding globular cluster is just inside that region where it can’t quite be viewed unaided, but even the smallest of binoculars will pick it out of a relatively starless field with ease. Holding a Class II designation, it was first discovered by Maraldi on September 11, 1746 and rediscovered independently by Messier exactly 14 years later. At a distance of roughly 37,500 light-years, it is estimated to contain in the neighborhood of 150,000 stars.

Even a small telescope will reveal M2’s rich and concentrated core region and slight ellipticity. Not bad for a 13 billion year old group of stars! As aperture increases, some of the brightest stars will begin to resolve, and in larger telescopes it will approach total resolution. You might well note a dark area in the northeastern section, and several more located throughout the splendid field. Feast your eyes on one of the finest in the skies!

Sunday, October 14 – Before dawn this morning, be sure to step outside and look at the splendid pairing of Venus and Saturn. The two bright planets will be separated by less than three degrees and present a wonderful photographic opportunity!

As the skies darken tonight, have a look at the Moon! If the lunar terminator has not advanced too far at your viewing time, have a look at the southeast shoreline of Mare Crisium for Agarum Promontorium. Look at how boldly it progresses northward across the dark plain before it disappears beneath the once molten lava. There were times in the past when great lunar observers had noted a mist-like appearance in this area – another transient lunar phenomenon.

Now let’s give deep sky a rest as we travel to the northwest corner of Capricornus and have a look just south of Alpha at beautiful Beta.

Named Dabih, this lovely white 3rd magnitude star has a very easily to split 6th magnitude companion which will appear slightly blue. Over 100 times brighter than our own Sun, the primary star is also a spectroscopic triple – one whose unseen companions orbit in a little over 8 days and 1374 days. Oddly enough the B star is also a very tight binary as well – yet the two major stars of this system are separated by about a trillion miles! If you have a large aperture telescope – power up. According to T. W. Webb, a 13th magnitude unrelated double is also found in between the two brighter stars. No matter if you chose binoculars or a telescope, I’m sure you’ll find the 150 light-year trip worth your time to add to your doubles list!

What’s Up this Week: October 1 – October 7, 2007

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Monday, October 1 – In 1897, the world’s largest refractor (40″) debuted at the dedication of the University of Chicago’s Yerkes Observatory. The immense telescope was 64 feet long and weighed 6 tons. Also today in 1958, NASA was established by an act of Congress. More? In 1962, the 300 foot radio telescope of the National Radio Astronomy Observatory (NRAO) went live at Green Bank, West Virginia. It held its place as the world’s second largest radio scope until it collapsed in 1988. (It was rebuilt as a 100 meter dish in 2000.)

Although first light for the 40″ was Jupiter, E. E. Barnard later discovered the third companion star to Vega using the Yerkes refractor. First “light” studies at Green Bank were a radio source galaxy and pulsar for NRAO. Tonight we’re going to turn our attention toward Pegasus and the incredible M15. Although we don’t have that much aperture to study with tonight, we can still get a very satisfactory look at M15 through any size binoculars or telescope.

You can find it easily just about two fingerwidths northwest of red Epsilon Pegasi (Enif). Shining brightly at magnitude 6.4, low power users will find it a delightfully tight ball of stars, but scope users will find it quite unique. As resolution begins, sharp-eyed observers will note the presence of a planetary nebula – Pease 1. This famous X-ray source you have just seen with your eyes may have supernovae remnants buried deep inside…

Tuesday, October 2 – If you’re up before dawn this morning, take a look at the Moon. You’ll find the “Red Planet” – Mars – less than a fistwidth south!

Tonight’s destination is not an easy one, but if you have a 6″ or larger scope, you’ll fall in love at first sight! Let’s head for Eta Pegasi and slightly more than four degrees north-northeast for NGC 7331.

This beautiful, 10th magnitude, tilted spiral galaxy is very much how our own Milky Way would appear if we could travel 50 million light-years away and look back. Very similar in structure to both our own Milky Way and the Great Andromeda Galaxy, this particular galaxy gains more and more interest as scope size increases – yet it can be spotted with larger binoculars. At around 8″ in aperture, a bright core appears and the beginnings of wispy arms. In the 10″ to 12″ range, spiral patterns begin to emerge and with good seeing conditions, you can see “patchiness” in structure as nebulous areas are revealed, and the western half is deeply outlined with a dark dustlane. But hang on…

Because the best is yet to come!

Wednesday, October 3 – Tonight return to NGC 7331 with all the aperture you have. What we are about to look at is truly a challenge and requires dark skies, optimal position and excellent conditions. Now breathe the scope about one half a degree south-southwest and behold one of the most famous galaxy clusters in the night.

In 1877, French astronomer Edouard Stephan was using the first telescope designed with a coated mirror when he discovered something a bit more with NGC 7331. He found a group of nearby galaxies! This faint gathering of five is now known as “Stephan’s Quintet” and its members are no further apart than the diameter of our own Milky Way galaxy.

Visually in a large scope, these members are all rather faint, but their proximity is what makes them such a curiosity. The Quintet is made up of five galaxies numbered NGC 7317, 7318, 7318A, 7318B, 7319 and the largest is 7320. Even with a 12.5″ telescope, this author has never seen them as much more than tiny, barely-there objects that look like ghosts of rice grains on a dinner plate. So why bother? Because I’ve seen them with large aperture…

What our backyard equipment can never reveal is what else exists within this area – more than 100 star clusters and several dwarf galaxies. Some 100 million years ago, the galaxies collided and left long streamers of their materials which created star forming regions of their own, and this tidal pull keeps them connected. The stars within the galaxies themselves are nearly a billion years old, but between them lie much younger ones. Although we cannot see them, you can make out the soft sheen of the galactic nuclei of our interacting group.

Enjoy their faint mystery!

Thursday, October 4 – Today in 1957, the USSR’s Sputnik 1 made space history as it became the first manmade object to orbit the earth. The Earth’s first artificial satellite was tiny, roughly the size of a basketball, and weighed no more than the average man. Every 98 minutes it swung around Earth in its elliptical orbit…and changed everything. It was the beginning of the “Space Race.” Many of us old enough to remember Sputnik’s grand passes will also recall just how inspiring it was. Take the time with your children or grandchildren to check heavens-above.com for visible passes of the ISS and think about how much our world has changed in just 50 years!

Tonight we’re headed towards the southwest corner star of the Great Square of Pegasus – Alpha. Our goal will be 11th magnitude NGC 7479 located about 3 degrees south (RA 23:04.9 Dec +12:19).

Discovered by Sir William Herschel in 1784 and cataloged as H I.55, this barred spiral galaxy can be spotted in average telescopes and comes to beautiful life with larger aperture. Also known as Caldwell 44 on Sir Patrick Moore’s observing list, what makes this galaxy special is its delicate “S” shape. Smaller scopes will easily see the central bar structure of this 105 million light-year distant island universe, and as aperture increases, the western arm will become more dominant. This arm itself is a wonderful mystery – containing more mass than it should and a turbulent structure. It is believed that perhaps a minor merger may have at one time occurred, yet no evidence of a companion galaxy can be found.

On July 27, 1990, a supernova occurred near NGC 7479’s nucleus and reached a magnitude of 16. When observed in the radio band, there is a polarized jet near the bright nucleus that is unlike any other structure known. If at first you do not see a great deal of detail, relax… Allow your mind and eye time to look carefully. Even with telescopes as small as 8-10″ structure can easily be seen. The central bar becomes “clumpy” and this well-studied Seyfert region is home to an abundance of molecular gas and forming stars.

Enjoy this incredible galaxy…

Friday, October 5 – Today marks the birthdate of Robert Goddard. Born 1882, Goddard is known as the father of modern rocketry – and with good reason.

In 1907, Goddard came into the public eye as a cloud of smoke erupted from the basement of the physics building in Worcester Polytechnic Institute where he had just fired a powder rocket. By 1914, he had patented the use of liquid rocket fuel and two- or three-stage solid fuel rockets. His work continued as he sought methods of putting equipment ever higher, and by 1920 he had envisioned his rockets reaching the Moon. Among his many achievements, he proved that a rocket would work in a vacuum, and by 1926 the first scientific equipment went along for the ride. By 1932, Goddard was guiding those flights and by 1937 had the motors pivoting on gimbals and controlled gyroscopically. His lifetime of work went pretty much unnoticed until the dawn of the Space Age, but in 1959 (14 years after his death) he received his acclaim at last as NASA’s Goddard Space Flight Center was established in his memory.

Today in 1923, Edwin Hubble was also busy as he discovered the first Cepheid variable in M31 – the Andromeda Galaxy. Hubble’s discovery was crucial in proving that objects once classed as “spiral nebulae” were actually independent and external stellar systems like our own Milky Way.

Tonight let’s look at a Cepheid variable as we head towards Eta Aquilae, almost a fistwidth due south of bright Altair.

Discovered by Edward Pigott in 1784, Eta is a Cepheid variable star around 1200 light-years away, but its beauty can be followed easily with the unaided eye. Ranging almost a full magnitude in a period of slightly over 7 days, this yellow supergiant is 3000 times brighter than our own Sun and around 60 times larger. Watch over the days as it takes about 48 hours to achieve maximum brightness and rivals nearby Beta – then falls slowly over the next 5 days.

Saturday, October 6 – While time and the stars appear to stand still and astronomical twilight begins earlier each night, let’s take one last look at the exiting constellation of Sagittarius. Our study for this evening is strictly a telescopic challenge for skilled observers. Set your sights about 2 degrees northeast of easy double 54 Sagittarii and around 7 degrees west of Beta Capricorni (RA 19 44 57.80 Dec -14 48 11.0) and let’s have a look at NGC 6822.

Often referred to as “Barnard’s Galaxy,” for its discoverer (E. E. Barnard – 1884), this unusual customer is actually a member of our local galaxy group. For the 4″ to 6″ telescope, this 11th magnitude, 1.7 million light-year distant object will not be easy, but it can be achieved with good conditions. Lower power is essential in even larger scopes, and those into the 12″ to 16″ range will see NGC 6822 burst into stunning resolution. This author has found that “Barnard’s Galaxy” almost appears like an open cluster overlaid with nebulosity, but the experienced eye will clearly see that the “shine” behind the stars is galactic in nature. It’s a very clumpy and unusual galaxy – one that I think you will very much enjoy. Be sure to look for small, pale blue, 10th magnitude planetary nebula NGC 6818 in the same field to the north-northwest. This pair rocks!

Sunday, October 7 – Today celebrates the birthday of Niels Bohr. Born 1885, Bohr was a pioneer Danish atomic physicist. If Niels were alive today, he’d be out early looking at the beautiful sight of Saturn, Venus and Regulus and the crescent Moon grouping together and gracing the predawn skies. It’s worth getting up for! For some lucky viewers, Regulus is so close to the Moon that it could be an occultation event. Be sure to check IOTA.

Now let’s get some practice in Capricornus as tonight we’ll take on a more challenging target with confidence. Locate the centermost bright star in the northern half of the constellation – Theta – because we’re headed for the “Saturn Nebula.”

Three finger-widths north of Theta you will see dimmer Nu, and only one finger-width west is NGC 7009 (RA 21 04 10.88 Dec -11 21 48.3). This wonderful blue planetary is around 8th magnitude and achievable in small scopes and large binoculars. NGC 7009 was the first discovery of Sir William Herschel on September 7, 1782 – the night he started his sky survey – and he cataloged it as H IV.1. Sir William’s original notes describe it as: “very bright nearly round planetary, not well-defined disk.”

When viewed by Lord Rosse in the 1840s, he gave it the nickname Saturn Nebula, and it is considered one of the nine Struve rare celestial objects. Also known as Bennett 127 and Caldwell 55, it is generally believed to be around 2400 light-years away – but not so far that it doesn’t make about every list known as an all time great!

Even at moderate magnification, you will see the elliptical shape which gave rise to its moniker. With larger scopes, those “ring like” projections become even clearer as the 11th magnitude central star becomes apparent. No matter which aperture you choose, this challenging object is well worth the hunt. You can do it!