New Solar Cycle Begins With New Year…

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According to the National Oceanic and Atmospheric Administration (NOAA), a new solar cycle is about to begin. The original forecast for Solar Cycle 24 was slated for March 2008, but the action is already under way as the first magnetically reversed sunspot of the new 11-year cycle has already appeared in the Sun’s northern hemisphere! Will it be strong or will it be weak? Time will tell… But if you live in a high latitude northern area? Be on alert tonight!

Last April an international panel of solar experts forecast that Solar Cycle 24 would start in March 2008, plus or minus six months. Upcoming solar storms definitely lay ahead, but neither the NOAA Space Environment Center in coordination with an international panel of solar experts predict a record-breaker. The most recent activity forecast was predicted for March with the peak occurring in late 2011 or mid-2012—up to a year later than expected. While original forecasts put the beginning activity a last Fall, the delay has simply left the experts guessing.

During a solar cycle, the frequency of sunspots rises and falls and spotting new activity may mean that the action is just heating up. These areas of intense magnetic activity on the Sun, can affect Earth by disrupting electrical grids, airline and military communications, GPS signals and even cell phones. During periods of intense sunspot activity, known as solar storms, highly charged radiation from the Sun may head toward Earth…

“Our growing dependence on highly sophisticated, space-based technologies means we are far more vulnerable to space weather today than in the past,” said NOAA Administrator Conrad C. Lautenbacher, Jr.

What does that mean for the Blue Planet’s inhabitants? There’s nothing to fear… except perhaps that it might be cloudy! Increased activity is a wonderful time to begin studying sunspots for yourself and to keep a eye out for aurora activity. Solar cycle intensity is measured in maximum number of sunspots—dark blotches on the sun that mark areas of heightened magnetic activity. The more sunspots there are, the more likely it is that major solar storms will occur.

“By giving a long-term outlook, we’re advancing a new field—space climate—that’s still in its infancy,” said retired Air Force Brig. Gen. David L. Johnson, director of the NOAA National Weather Service. “Issuing a cycle prediction of the onset this far in advance lies on the very edge of what we know about the Sun.”

NOAA, an agency of the U.S. Commerce Department, is celebrating 200 years of science and service to the nation and the world. The NOAA Space Environment Center also is the world warning agency of the International Space Environment Service, a consortium of 11 member nations that generate a first alert of solar activity and its affects on Earth and you, too, can check out the information here! Stay tuned as “Universe Today” brings you guidelines on how you can solar observe and when you can possibly expect aurora in your area! As it stands, a high-speed solar wind stream is already buffeting Earth’s magnetic field and this could spark a geomagnetic storm. For high latitude observers, this means you may see the aurora tonight!!

The Moon Meets Antares On January 5

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Although no one likes to get up early, it will be worth it on the morning of January 5. For dedicated SkyWatchers, you’ll enjoy the pleasing view of Venus and the last phases of the waning Moon… But look closely, because you’ll see brilliant red Antares is also joining the show! Whenever a bright star like Antares is so close to the lunar limb, chances are an occultation event is about to happen for some area of the Earth. Would you like to learn more? A photographic and scientific opportunity awaits you!

Less than half a degree away from the lighted edge of the crescent Moon, Antares will make a picturesque scene for many of us that only nature can create. For a few lucky viewers in the south-western portion of South America, this could be an occultation event! If you’ve ever wondered about occultations, then it’s time to learn more about what an occultation is, when it happens, how to view it, record and report.

Antares Occultation Path

Several times a year the natural progress of the Moon against the progress of the starry background means a chance to see the lunar disk occult (or cover up) a bright star or planet. If the object is bright enough, you can watch this happen with only your eyes, but even binoculars or a small telescope will greatly improve the view. What a pleasure it is to see a star simply disappear behind the Moon’s limb! But it’s not just the Moon that occults stars – so do asteroids. Occultations happen anytime one celestial body passes in front of another – a type of eclipse. For those of you who enjoy doing a little bit of science, there’s a whole lot more to do… and contributions you can make!

Thanks to great folks at the International Occultation Timing Association (IOTA), you can learn how to predict, time, record and submit your observations by downloading the free ebook: “Chasing the Shadow: The IOTA Occultation Observer’s Manual – The Complete Guide to Observing Lunar, Grazing and Asteroid Occultations” available here! It’s the only book of its kind that shows observers how to get started in occultations and what equipment to use. Whether you are a novice observer, or an advanced observer with a video system, you can assist in the search for asteroidal moons, help discover new double stars and help determine the size of the Sun during solar eclipses.

Let the beauty of the morning on January 5 inspire you! During the month of January you’ll be treated to great things like an occultation of the Pleiades stars on January 18 in northern North America and Northern Asia. On January 19 in southern Africa you’ll see Beta Tauri disappear. If you live in Alaska, January 20 means an occultation of Mars. For southern observers in Australia and New Zealand, be sure to check out the Moon and Regulus on January 24. To get times and locations, all you have to do is check with IOTA. If watching a asteroid pass in front of a star takes your fancy, then stop by here where you can get multitudes of information for events in your area!

In the meantime, get your cameras and fingers ready. We’d like to share in your success! See if you can capture the view on the morning of January 5 and post it here. Even if you’re not able to photograph the event, we’d love to hear your reports and impressions. Watch the “Universe Today” in future months as we bring you more!

Quadrantid Meteor Shower Will Sparkle on January 3rd

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Beginning each New Year and lasting for nearly a week, the Quadrantid Meteor Shower sparkles across the night sky for nearly all viewers around the world. Its radiant belongs to an extinct constellation once known as Quadran Muralis, but any meteors will seem to come from the general direction of bright Arcturus and Boötes. This is a very narrow stream, which may have once belonged to a portion of the Aquarids, but recent scientific data points to a what may have been a cosmic collision.

According the most recent data, the Quandrantid meteors may have been formed about five centuries ago when a near-Earth asteroid named 2003 EH1 and a comet smashed into one another. Historic records from ancient China put comet C/1490 Y1 in the path of probability. As Jupiter’s gravity continues to perturb the stream, another 400 years may mean this shower will become as extinct as the constellation for which it was once known… But NASA scientists and astronomers are taking to the skies to study the event.

A Gulfstream V aircraft will fly scientists and their instruments for 10 continuous hours over the Arctic to observe and record meteor activity. From above the Earth, the stream can be studied without light pollution and clouds to determine when the activity peaks and how the stream is dispersed. “We will fly to the North Pole and back to compensate for Earth’s rotation and to keep the stream in view throughout the flight,â€? said Peter Jenniskens, a principal investigator at NASA’s Ames Research Center.

According to NASA, scientists believe this could be the most brilliant meteor shower in 2008 with over 100 visible meteors per hour at its peak. Best viewing times with the highest meteor rates are expected to be in either the late evening of Jan. 3 over Europe and western Asia or the early morning of Jan. 4 over the eastern United States. For the USA: 6pm – 2am (Pacific Time) on Jan. 3 and 4, 2008. For Northern Europe: 2am – 10am (London) on Jan. 4, 2008. For Northern Asia: 11am – 7pm (Tokyo) on Jan. 4, 2008. For almost of us, this means bundling up against the cold and battling the remnants of the waning Moon… But the sight of even one “shooting star” can make the trip worthwhile!

Will the Quadrantid Meteor Shower live up to its expectations? No one knows for sure… But we’ll be watching!

What’s Up this Week: December 24 – December 31, 2007

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Please note that this is going to be the last edition of the What’s Up series of articles on Universe Today. From here on out, Tammy’s daily skywatching guide will be published in a book called the Night Sky Companion. Tammy is still writing for Universe Today, and will be posting articles about skywatching and events on a regular basis.

Monday, December 24 – Twas the night before Christmas in a sky filled with stars… And low on the horizon are the Yule Moon and Mars! That’s right. It’s the Full Yule Moon, and arriving at the same time Mars reaches opposition. For many viewers, the spectacular pair will rise with Mars less than a degree south of Luna… But a pairing this close means a few lucky observers could be in for an occultation event! Be sure to check IOTA for possible times and locations.

Today in 1968, Apollo 8 became the first manned spacecraft to orbit the Moon. Let’s celebrate that by having a look at the lunar surface. On the eastern limb we see the bright splash ray patterns surrounding ancient Furnerius – yet the rays themselves emanate from much younger crater Furnerius A. All over the surface, we see small points light up and the testament to the Moon’s violent past written in its scarred lines. Take a look now at the western limb… For the sunrise is about to advance around it.

Until this date, no man had seen with his own eyes what lay beyond. Frank Borman, James Lovell and William Anders were to become the first to directly view the “dark side” and the first to witness earthrise over the Moon. As the days ahead bring the terminator around to the eastern limb, let your mind take flight to the distant orb and enjoy its landscape as the shadows take on new angles and old features become new again.

“And from the crew of Apollo 8, we close, with good night, good luck, a Merry Christmas, and God bless all of you, all of you on the good Earth.” (Astronaut Frank Borman)

Tuesday, December 25 – Wishing you all the very best for the Christmas season! Like a present, Sir Isaac Newton was born on this day 1642 – Newton was the British “inventor” of calculus and a huge amount of what we now consider modern classical physics. Even young children are aware of his simple laws of motion and gravity. It wasn’t until the time of Einstein until things changed!

In keeping with the season, tonight’s astronomical object is a celebration of both starlight and asterism. Located 10 degrees east of Betelgeuse (RA 06 41 00.00 Dec +09 53 -0.0), NGC 2264 will be a challenging object thanks to the Moon. Also known as the “Christmas Tree Cluster,” this bright asterism of approximately 20 bright stars and over 100 fainter ones is embroiled in a faint nebula that will be lost to bright skies, leaving only the delightful Christmas tree shape adorned with stars.

The very brightest of these stars, S Monocerotis, is 5th magnitude and will show clearly in the finderscope, and will be seen as a double at magnification. Steady skies will reveal that the “star” at the top of our “tree” is also a visual double. Many of the stars will also appear to have companions, as well as tints of silver as gold. The visual effect of this splendid open cluster is well worth the challenge it presents. Happy Holidays!

Wednesday, December 26 – Is it gone yet? Nope. The Moon will rise a little later this evening, but we’re going to run ahead of it tonight and enjoy some studies in Auriga! Looking roughly like a pentagon in shape, start by identifying the brightest of these stars – Capella. Due south of it is the second brightest star, El Nath. By aiming binoculars at El Nath, go north about one-third the distance between the two and enjoy all the stars!

You will note two very conspicuous clusters of stars in this area, and so did Le Gentil in 1749. Binoculars will reveal the pair in the same field, as will telescopes using lowest power. The dimmest of these is M38, and it will appear vaguely cruciform in shape. At roughly 4200 light-years away, larger aperture will be needed to resolve the 100 or so fainter members. About two and a half degrees to the southeast you will see the much brighter M36. More easily resolved in binoculars and small scopes, this “jewel box” galactic cluster is quite young – and about 100 light-years closer!

Thursday, December 27 – Born today in 1571 was Johannes Kepler – Danish astronomer and assistant to Tycho Brahe. Kepler used Brahe’s copious notes of Mars’ positions to help formulate his three laws of planetary motion. These laws are still in use today.

Is it gone yet? No. The Moon will be along shortly, but we still have time to set our sights about halfway between Theta Aurigae and El Nath. Our study object will be the open cluster M37. Apparently discovered by Messier himself in 1764, this galactic cluster will appear almost nebula-like to binoculars and very small telescopes – but comes to perfect resolution with larger instruments.

At around 4700 light-years away, and spanning a massive 25 light-years, M37 is often billed as the finest of the three Aurigan opens for bigger scopes. Offering beautiful resolvability, this one contains around 150 members down to magnitude 12, and has a total population in excess of 500.

What makes it unique? As you view, you will note the presence of several red giants. For the most part, open clusters are comprised of stars that are all about the same age, but the brightest star in M37 appears orange in color and not blue! So what exactly is going on in here? Apparently some of these big, bright stars have evolved much faster – consuming their fuel at an incredible rate. Other stars in this cluster are still quite young on a cosmic scale, yet they all left the “nursery” at the same time! In theory, this allows us to judge the relative age of open clusters. For example, M36 is around 30 million years old and M38 about 40, but the presence of the red giants in M37 puts its estimated age at 150 million years! Just awesome…

Friday, December 28 – Today we celebrate the birth of Arthur S. Eddington. Born in 1882, Eddington was a British theoretical astrophysicist whose work was fundamental to interpreting and explaining stellar nature. He also coined the phrase “expanding universe” to refer to the mutual recession of the galaxies.

Is it gone yet? Not yet… But before the Moon rises tonight, let’s enjoy the early dark skies and go to our maps west of M36 and M38 to identify AE Aurigae. As an unusual variable, AE is normally around 6th magnitude and resides approximately 1600 light-years distant. The beauty in this region is not particularly the star itself but the faint nebula in which it resides. Known as IC 405, this is an area of mostly dust and very little gas. What makes this view so entertaining is that we are looking at a “runaway” star.

It is believed that AE originated in the M42 region in Orion. Cruising along at a very respectable speed of 130 kilometers per second, AE flew the “stellar nest” some 2.7 million years ago! Although IC 405 is not directly related to AE, there is evidence within the nebula that areas have been cleared of their dust by the rapid northward motion of the star. AE’s hot, blue illumination and high energy photons fuel what little gas is contained within the region, and its light reflects off the surrounding dust as well. Although we cannot “see” with our eyes like a photograph, together this pair makes an outstanding view for the small backyard telescope, and it is known as “The Flaming Star.”

And when the Moon rises? Look for Regulus less than one half degree to its north and Saturn another two degrees further. This could be an occultation of Regulus, so be sure to check IOTA!

Saturday, December 29 – If you’re up before dawn this morning, take the time to step outside and view the simple beauty of the ecliptic plane. To the west, Mars hangs just above the horizon with Saturn not far above it. The Moon dances high overhead and Venus shines just before the rising Sun. In a matter of weeks, Jupiter will return again to the morning skies!

Is it gone yet? Not yet. Since the Moon won’t begin to interfere for quite a while after the skies turn dark, this would be a great opportunity to locate an easy Messier object – M34. If you remember our previous study stars Almach and Algol, you’re halfway there. Draw an imaginary line between them and look with your binoculars or finder scope just a shade north of center.

In binoculars, M34 will show around a dozen fainter stars clustered together, and perhaps a dozen more scattered around the field. Small telescopes at low power will appreciate M34 for its resolvability and the distinctive orange star in the center. Larger aperture scopes will need to stay at lowest power to appreciate the 18 light-year span of this 100 million year old cluster, but take the time to power up and study. You will find many challenging doubles inside!

Sunday, December 30 – Is it gone yet? Not quite! The Moon will be along much later, but not before we’ve had an opportunity to head for another northern gem, M76.

Located in western Perseus just slightly less than one degree north-northwest of Phi, M76 is often referred to as “The Little Dumbbell.” Originally discovered by Messier’s assistant MÈchain in September of 1780, Charles didn’t get around to cataloging it for another six weeks. What a shame it took him so long to view this fine planetary nebula! Its central star is one of the hottest known, but its resemblance to M27 is what makes it so fascinating.

Looking very much like a miniaturization of the much larger M27, M76 is rather faint at magnitude 11, but is quite achievable in scopes of 114mm in aperture or larger. It is small, but its irregular shape makes this planetary nebula a real “class act!”

For our Southern Hemisphere friends, get thee out there and view Eta Carinae! First recorded by Halley in 1677, this nebular variable star left even the great Sir John Herschel at a loss to describe its true beauty and complexities. This “slow nova” is filled with all the wonders that we “northerners” can only dream about…

Monday, December 31 – Today is the birthday of Robert G. Aitken. Born in 1864, Aitken was a prolific American observer who discovered and catalogued more than 3100 double and binary stars. Just look at what a prolific observer YOU have become in just a year!

Is it gone yet? No. The Moon will be around much later tonight, but the year 2007 is just about ended. Try celebrating in a unique and inspiring way! Go observing…

In the hours before midnight, you could take a cosmic journey that spans millions of light-years. In the northern hemisphere, visit with the Andromeda Galaxy again – or the Small and Large Magellanic Clouds if you live in the South. Feast your eyes on vast and wondrous displays of stars like the “Double Cluster” in Perseus, or the “Jewel Box” – the Kappa Crucis star cluster. Rejoice in the birth of new stars by voyaging to M42 – the Orion Nebula… And remember the old by returning to M1 – the Crab Nebula. Take delight in the movements of our own solar system by watching Mars rise, or peeking in on Saturn’s rings as it follows behind. Perhaps the ISS will make a pass over your area tonight, or maybe only a single star will shine through your cloudy sky. It may be something as spectacular as watching a meteor go down in a blaze of glory, or as quiet and contemplative as watching the Moon rise as the year ends.

Now take a moment to look up at the stars and think about all the billions of years that they have been in the making and all the time that it has taken for the light to reach us. Salute! Our observing year has been wonderful together… And I’ll look for you under the stars! I hope you’ll join me again when 2008 begins as “The Night Sky Companion.”

May all your journeys be at light speed!

What’s Up this Week: December 17 – December 23, 2007

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Monday, December 17 – Tonight there are craters galore to explore: Plato, Aristotle, Eudoxus, Archimedes… But let’s head to the north of Sinus Medii and have a look at a pair we’ve not yet encountered on our lunar travels – Agrippa and Godin. The larger of the two, Agrippa, measures around 46 kilometers in diameter and drops to a depth of 3070 meters. To the south is Godin, which is somewhat smaller at 35 kilometers in diameter, but a bit deeper at 3200 meters. Note how Godin’s interior slopes towards its central peak.

With deep sky studies improbable for the next few days, why don’t we try taking a look at another interesting variable star? RT (star 48) Aurigae is a bright Cepheid that is located roughly halfway between Epsilon Geminorum and Theta Aurigae. This perfect example of a pulsating star follows a precise timetable of 3.728 days and fluxes by close to one magnitude.

Located 1600 light-years away, RT was first discovered in 1905 by T. H. Astbury of the British Astronomical Association. Like all Cepheids, it expands and contracts rhythmically – for reasons science is not completely sure of. Yet, we do know that it takes about 1.5 days for it to expand to its largest and brightest and 2.5 days for it to contract, cool, and dim.

Tuesday, December 18 – Tonight on the south shore of the emerging Mare Nubium, look for ancient craters Pitatus and Hesiodus right on the terminator. During this phase, something wonderful can happen! If you are at the right place at the right time, sunlight will shine briefly through a break in Hesiodus’ wall and cast an incredible ray across the lunar surface! If you don’t catch it, you can still enjoy one of the few concentric craters on the Moon.

Want a challenging double this evening? Then let’s have a look at Theta Aurigae located on the east side of the pentagonal shape of this constellation.

Located about 110 light-years away, 2.7 magnitude Theta is a four star system, whose members range in magnitude from 2.7 to 10.7. Suited even to a small telescope, the brightest member – Theta B – is itself a binary at magnitude 7.2, and was first recorded by Otto Struve in 1871. The pair moves quite slowly, and may take as long as 800 years to orbit each other at their separation of about 110 AU. The furthest member of this system was also noted by Struve as far back as 1852, but it is not a true member – the separation only occurring thanks to Theta’s own proper motion.

While you are there, be sure to note Theta’s unusual color. While it will appear “white,” look closely at the diffraction caused by our own atmosphere which acts much like a prism… You’ll notice a lot more purple and blue around this star than many others of the same spectral type. Why? Theta is a silicon star!

Wednesday, December 19 – While the mighty Copernicus on the terminator will draw the eye like no other crater tonight, it’s time to pick up another study which you may not have logged – Crater Davy. You will find it just west of the large ring of Ptolemaeus on the northeastern edge of Mare Nubium. It will appear as a small, bright ring, with the large crater Davy A on its southern border. Now skip across the grey sands of Nubium further west and let’s take a look at the crater on the peninsula-like feature Guericke. Named for Dutch physicist Otto von Guericke, this 58 kilometer diameter crater has all but eroded away. Look for a break in its eastern wall and notice how lava flow has eradicated the north!

Now, for apparently no good reason, let’s head for Alpha Persei (Mirfak). While there’s nothing particularly interesting about this 570 light-year distant star, what is incredible is the field in which it resides! Take a look at lowest power with a rich field telescope or binoculars and be prepared to be blown away…

This is the Alpha Persei moving group – a fantastic field of main sequence stars that contains a little over 100 members. Even though it will take 90,000 years before any perceptible change is seen in this bright collection, they are happily moving at a pace of about 16 kilometers per second towards Beta Tauri! Enjoy this fine group also known as Melotte 20…

Thursday, December 20 – Tonight is the peak of the Delta Arietid meteor shower. While most showers are best after midnight, this is an early evening shower that must be viewed before the radiant sets. The fall rate is modest – about 12 per hour.

On the lunar surface, we’re going to head to the deep south as we pick up one of the last of our lunar studies – Longomontanus. Named for the Danish Astronomer Christian Longomontanus (an assistant to Tycho Brahe), this wonderland of details stretches around 145 kilometers across the surface. Look for a great collection of interior craters along its northwest interior wall and note how it has eradicated a much older crater which still shows an edge to the east.

Today marks the founding of Mt. Wilson Solar Observatory. It officially opened its doors in 1904. We also celebrate the birth of Walter S. Adams on this date. Born in 1876, Adams was the astronomer at Mt. Wilson who revealed the nature of Sirius B, the first known white dwarf star. Sirius B was first seen by Alvan Clark in 1862 and most recently, the Hubble Space Telescope precisely measured the mass of B for the first time. While Sirius is far too low at an early hour to study its white dwarf, we can have a look at a similar star when we view Omicron 2 Eridani located roughly a handspan west of Rigel. As the southernmost of the Omicron pair, it is sometimes known as 40 Eridani, and you’ll find it to be an interesting multiple star system that’s very worthy of your time.

Discovered by William Herschel in 1783, this 16 light-year distant system is the eighth nearest of the unaided visible stars. Well spaced from the primary, the companion star is also a double for high powers and will reveal a red dwarf discovered by Otto Struve. Now, look closely at the 9th magnitude B star. This is the only white dwarf that can be considered “easy” for the backyard telescope. Its diameter is only about twice the size of Earth and its mass is about that of our Sun. Power up and locate the 11th magnitude companion…for it’s one of the least massive stars known! And this white dwarf may be the smallest stellar object visible in an amateur telescope – it would be like spotting a tennis ball…on the moon!

Friday, December 21 – Ah, yes… Is there any more beautiful crater on the Moon than graceful Gassendi? While we have visited it before, take the time to power up and enjoy its features. Look for rimae which crisscross the shallow floor, and the strong A crater which mars its northern wall. How many of its interior features can you resolve?

While we’re out, let’s have a look at one of the best known double stars in the night – Gamma Arietis (RA 01 53 31.81 Dec +19 17 37.9).

Also known as Mesarthim, this combined magnitude 4 beauty was unintentionally discovered in 1664 by Robert Hooke who was following a comet. While no real change has been spotted in the more than 343 years since that time, there has been a slight difference detected in the components’ radial velocities. Roughly 160 light-years away, you’ll enjoy this almost matched-magnitude pair of white stars – but look carefully: in 1878, S. W. Burnham found a third star nearby that might not be a physical member, but is also a double!

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

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

Today marks Winter Solstice – for the northern hemisphere, the shortest day and the longest night of the year – and the point when the Sun is furthest south. Now is a wonderful time to demonstrate for yourself our own movements by choosing a “solstice marker.” Anything from a fence post to a stick in the ground will suffice! Simply measure the shadow when the Sun reaches the zenith and repeat your experiment in the weeks ahead and watch as the shadow grows shorter…and the days grow longer!

And be sure to look at the Moon tonight as well, for it is at perigee – its closest point to the Earth. While you might hear a tall tale or two about it being brighter than normal since it is also close to Full, judge for yourself! And be sure to look for signs of libration while you’re there…

Sunday, December 23 – While the Moon will command tonight’s skies, we can still have a look at a tremendous star as we head 150 light-years away to Menkar…

Better known as Alpha Ceti, you’ll find this nearly second magnitude giant orange beauty just west of Orion’s “bow” (RA 03 02 16.77 Dec +04 05 23.0). With even a small telescope, you will also see 5th magnitude 93 Ceti in the eyepiece as well! Although they are not a true physical pair (the blue 93 is 350 light-years further away), they make a wonderful color contrast which is well worth your time. Just think… If 93 were as close as Menkar, it would be 250% brighter. But up the magnification and see if you can spot another true double in the field!

Tonight in 1672, astronomer Giovanni Cassini discovered Saturn’s moon Rhea. Although you will have to wait until a little later in the evening to catch the ringed planet, why not try your hand at finding Rhea as well? A well-collimated scope as small as 4.5″ is perfectly capable of seeing Tethys, Rhea and Dione as they orbit very nearly to the edges of the ring system. All it requires is steady skies and a little magnification!

What’s Up this Week: December 10 – December 16, 2007

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Monday, December 10 – If you are out stargazing until the morning hours, look for the peak of the Monocerid meteor shower. Its fall rate is around one per hour and its radiant point is near Gemini.

Tonight let’s go north for a mid-size scope challenge about two fingerwidths east-northeast of the beautiful double star Gamma Andromedae (RA 02 22 32.90 Dec +43 20 45.8).

The 12th magnitude NGC 891 is a perfect example of a spiral galaxy seen edge-on. To the mid-sized scope, it will appear as a pencil-slim scratch of light, but larger telescopes will be able to make out a fine, dark dust lane upon aversion. Discovered by Caroline Herschel in 1783, NGC 891 contained a magnitude 14 supernova event recorded on August 21, 1986. Often considered a “missed Messier,” you can add this one to your Caldwell list as number 23!

Tuesday, December 11 – On this date in 1863, Annie Jump Cannon was born. She was a United States astronomer who created the modern system for classifying stars by their spectra. Why not celebrate this achievement by coming along with me and viewing some very specific stars that have unusual visual spectral qualities! Let’s grab a star chart, brush up on our Greek letters and start first with Mu Cephei.

Nicknamed the “Garnet Star,” this is perhaps one of the reddest stars visible to the unaided eye. At around 1200 light-years away, this spectral type M2 star will show a delightful blue/purple “flash.” If you still don’t perceive color, try comparing Mu to its bright neighbor Alpha, a spectral type A7, or “white,” star. Perhaps you’d like something a bit more off the beaten path? Then head for S Cephei about halfway between Kappa and Gamma toward the pole. Its intense shade of red makes this magnitude 10 star an incredibly worthwhile hunt.

To see an example of a B spectrum star, look no further than the Pleiades… All the components are blue white. Want to taste an “orange?” Then look again at Aldeberan, or Alpha Tauri, and say hello to a K spectrum star. Now that I have your curiosity aroused, would you like to see what our own Sun would look like? Then choose Alpha Aurigae, better known as Capella, and discover a spectral class G star that’s only 160 times brighter than the one that holds our solar system together! If you’re enjoying the game, then have a look at a star with one of the most unusual spectra of all – Theta Aurigae. Theta is actually a B class, or a blue/white, but instead of having strong lines in the helium, it has an abnormal concentration of silicon, making this incredibly unusual double star seem to glitter like a “black diamond.”

Still no luck in seeing color? Don’t worry. It does take a bit of practice! The cones in our eyes are the color receptors and when we go out in the dark, the color-blind rods take over. By intensifying the starlight with either a telescope or binoculars, we can usually excite the cones in our dark-adapted eyes to pick up on color.

Tonight is also the peak of the Sigma Hydrid meteor stream. Its radiant is near the head of the Serpent and the fall rate is also 12 per hour – but these are fast!

Wednesday, December 12 – Today in 1961, OSCAR-1 was launched. The project started in 1960; the name stands for Orbital Satellite Carrying Amateur Radio. OSCAR-1 operated in orbit for 22 days, transmitting a signal in Morse Code – the simple greeting “Hi.” The success of the mission helped to promote interest in amateur radio which still continues to this day!

Tonight before the Moon interferes with fainter studies, let’s head far north for one of the oldest galactic clusters in our visible sky – NGC 188.

Hovering near Polaris (RA 00 44.5 Dec +85 20) this circumpolar open cluster also goes by other names: Collinder 1 and Melotte 2. Discovered by John Herschel on November 3, 1831, this 8th magnitude collection of faint stars will require a telescope to resolve its 120 members. At one time, it was believed to be as old as 24 billion years, later updated to 12 billion; but it is now considered to be around 5 billion years old. No matter how old it may truly be, it is one of the time-honored great studies and is also number one on the Caldwell list!

Thursday, December 13 – Today in 1920, the first stellar diameter was measured by Francis Pease with an interferometer at Mt. Wilson. His target? Betelgeuse!

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

So why are the Geminids such a mystery? Most meteor showers are historic – documented and recorded for hundred of years – and we know them as being cometary debris. When astronomers first began looking for the Geminids’ parent comet, they found none. It wasn’t until October 11, 1983 that Simon Green and John K. Davies, using data from NASA’s Infrared Astronomical Satellite, detected an orbital object (confirmed the next night by Charles Kowal) that matched the Geminid meteoroid stream. But this was no comet, it was an asteroid.

Originally designated as 1983 TB, but later renamed 3200 Phaethon, this apparently rocky solar system member has a highly elliptical orbit that places it within 0.15 AU of the Sun about every year and half. But asteroids can’t fragment like a comet – or can they? The original hypothesis was that since Phaethon’s orbit passes through the asteroid belt, it may have collided with other asteroids creating rocky debris. This sounded good, but the more we studied the more we realized the meteoroid “path” occurred when Phaethon neared the Sun. So now our asteroid is behaving like a comet, yet it doesn’t develop a tail.

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

Thanks to the wide path of the stream, folks the world over get an opportunity to enjoy the show. The traditional peak time is tonight as soon as the constellation of Gemini appears around mid-evening. The radiant for the shower is right around bright star Castor, but meteors can originate from many points in the sky. From around 2 am tonight until dawn (when our local sky window is aimed directly into the stream) it’s possible to see about one “shooting star” every 30 seconds.

The most successful of observing nights are ones where you are comfortable, so be sure to use a reclining chair or pad the ground while looking up. Please get away from light sources when possible – it will triple the amount of meteors you see. Enjoy the incredible and mysterious Geminids!

Friday, December 14 – Today was a very busy day in astronomy history. Tycho Brahe was born in 1546. Brahe was a Danish pre-telescopic astronomer who established the first modern observatory in 1582 and gave Kepler his first job in the field. In 1962, Mariner 2 made a flyby of Venus and became the first successful interplanetary probe. As we begin our evening on the Moon, be sure to check with IOTA for a possible occultation event in your area. Neptune is less than a degree away to the north!

On this day in 1972, the last humans (so far) to have walked on the lunar surface returned to Earth. Eugene Cernan left the final bootprint at Taurus-Littrow and called it the “end of the beginning.” As we reach the end of our observing year, let this only be the beginning for you as we look to that distant orb to seek out the Apollo 17 landing area.

You have learned so much over the last 12 months! Even if the terminator has not progressed as far as the illustration shows, you should know the approximate location of Posidonius on the surface and recognize Mare Crisium and the Taurus Mountains to its east as well as the small, grey expanse of Sinus Amoris between them. Littrow is on its western shore, and although it is rather small with a 31 kilometer diameter, Mons Vitruvius will shine like a beacon to the south.

Enjoy your Moon walk!

Saturday, December 15 – Today in 1970, the Soviet spacecraft Venera 7 registered a first as it made a successful soft landing on Venus, and so went into the history books as the first craft to land on another planet. You can catch Venus yourself in the pre-dawn skies!

Tonight, one of the most outstanding features on the lunar surface will be the southern crater Maurolycus. Although we have visited it before, look again! At an overall diameter of 114 kilometers, this double impact crater sinks below the surface to a depth of 4730 meters and displays a wonderful multiple mountain-peaked center. If you have not collected Gemma Frisius for your studies, you will find it just north of this grand crater, looking much like a “paw print” at low power.

Now let’s travel 398 light-years away as we have a look at AR Aurigae – the centermost star in a brilliant collection. It is about one-third the distance from southern Beta to northern Alpha (Capella). AR is an eclipsing binary which consists of two main sequence white dwarf stars. About every 4.1 days, this pair will make a slight magnitude drop. While both are chemically peculiar, neither fills its Roche Lobe – meaning they are not stripping material from each other to cause these unusual abundances. Recent studies have shown the possibility of a third, unseen companion! But even binoculars will see that AR resides in a great field of stars and is worth a little of your time…

Sunday, December 16 – With only nine days left until the holiday, astronomers have recently discovered a unique feature on the lunar surface. While accepted for many years to be a natural feature of selenography, modern photography coupled with today’s high powered telescopes have discovered an area near the lunar North Pole that’s being used as a runway by a man in a red suit piloting an unusual spacecraft. Be sure to spark the imaginations in your young viewers as you show them the Alpine Valley!

Today we celebrate the birthday of Edward Emerson (E. E.) Barnard. Born in 1857, Barnard was an American observational astronomer and an absolute legend. He led a very colorful life in astronomy, and his sharp skills have led to a multitude of discoveries. His life was a very fascinating one: Barnard was often known to simply set the scope on one point in the sky and just watch for new objects as the field moved! Tonight let’s take a look at a bright star that has Barnard’s touch, as we explore Beta Aurigae – Menkalinan.

First identified as a spectroscopic binary by A. Maury in 1890, Beta itself is part of a moving group of stars that includes Sirius, and is an Algol-type variable. While you won’t see changes as dramatic as those of the “Demon Star,” it has a precise drop of 0.09 magnitude every 3.96 days. This system contains almost identical stars which are more than two and a half times the size of our Sun, but they orbit each other at a distance of less than 0.1 AU! While Menkalinan’s 10th magnitude optical companion was first spotted by Sir William Herschel in 1783, only E. E. Barnard noticed the 14th magnitude true tertiary to this incredible multiple system!

The Geminids Meet Mars…

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The evening of December 13th and dawn December 14th of will bring one of the most hauntingly beautiful and mysterious displays of celestial fireworks all year – the Geminid meteor shower crowned by Mars.

The Geminid meteor shower was first noted in 1862 by Robert P. Greg in England, and B. V. Marsh and Prof. Alex C. Twining of the United States in independent studies. The annual appearance of the Geminid stream was weak initially, producing no more than a few per hour, but it has grown in intensity during the last century and a half. By 1877, astronomers had realized this was a new annual shower – producing about 14 meteors per hour. At the turn of the last century, the rate had increased to over 20; and by the 1930s, up to 70 per hour. Only ten years ago observers recorded an outstanding 110 per hour during a moonless night… And the Moon on this night will soon set leaving brilliant Mars to lead the way!

So why are the Geminids such a mystery? Most meteor showers are historic – documented and recorded for hundreds of years – and we know them as originating with cometary debris. But when astronomers began looking for the Geminids’ parent comet, they found none. It wasn’t until October 11, 1983 that Simon Green and John K. Davies, using data from NASA’s Infrared Astronomical Satellite, detected an object (confirmed the next night by Charles Kowal) that matched the orbit of the Geminid meteoroid stream. But this was no comet, it was an asteroid – in fact, a 14th magnitude asteroid which is passing Earth tonight from a distance of less than 18 million kilometers! Now considered a Potential Hazardous Asteroid (PHA), 3200 Phaeton comes within 3.2 million kilometers of Earth’s orbit about every 17 months. You can locate Phaeton on the night of the 13/14th about 02:00:00 UT using this finderchart!

Phaeton Map

Originally designated as 1983 TB, but later renamed 3200 Phaethon, this apparently rocky solar system member has a highly elliptical orbit that places it within 0.15 AU of the Sun during every solar system tour. But asteroids can’t fragment like a comet – or can they? The original hypothesis was that since Phaethon’s orbit passes through the asteroid belt, it may have collided with one or more asteroids, creating rocky debris. This sounded good, but the more we studied the more we realized the meteoroid “path” occurred when Phaethon neared the Sun. So now our asteroid is behaving like a comet, yet it doesn’t develop a tail.

So what exactly is this “thing?” Well, we do know that 5.1 kilometer diameter Phaethon orbits like a comet, yet has the spectral signature of an asteroid. By studying photographs of the meteor showers, scientists have determined that the meteors are denser than cometary material, yet not as dense as asteroid fragments. This leads them to believe Phaethon is probably an extinct comet which has gathered a thick layer of interplanetary dust during its travels, yet retains the ice-like nucleus. Until we are able to take physical samples of this “mystery,” we may never fully understand what Phaethon is, but we can fully appreciate the annual display it produces!

Thanks to the wide path of the stream, folks the world over get an opportunity to enjoy the show of the Geminids and Mars. The traditional peak time is tonight as soon as the constellation of Gemini appears, around mid-evening. The radiant for the shower is near the bright star Castor – less than a handspan northeast of Mars – but meteors can originate from many points in the sky. From around 2 AM tonight until dawn (when our local sky window is aimed directly into the stream) it is possible to see about one “shooting star” every 30 seconds. The most successful of observing nights are ones where you are comfortable, so be sure to use a reclining chair or pad on the ground while looking up… And dress warmly! Please get away from light sources when possible – it will triple the amount of meteors you see. Enjoy the incredible and mysterious Geminids and Mars!

Written By: Tammy Plotner

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!

Perseus, Hero of the Night

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With the Moon quickly departing early evening skies, now is the time to find a hero. Thanks to attention Comet 17/P Holmes has generated, many SkyWatchers have now become familiar with the constellation Perseus, but there’s a lot more there than just a comet! Only a few days ago, Holmes passed a wonderful bright star named Mirfak – a part of the Alpha Persei Association. Viewable with the unaided eye, but best in binoculars, this young, moving cluster is also known as Melotte 20 or Collinder 39 and is around 601 light years away. What a treat to catch a comet overlaying a star cluster!

But that’s not all… As the old year ends and a new one begins, Comet Holmes will sweep round to visit with Messier 34. At a little fainter than magnitude 5, you might be able to spot this 1400 light year distant star cluster as a hazy patch with just your eyes, but its full-moon size will make it a special treat in binoculars as Holmes passes it by!

As Comet Holmes continues to spread and dim, it will round its orbital turn and head towards a great variable star – Beta Persei. For readers, the “Demon Star” – Algol – is a familiar target, but what a treat to catch this eclipsing variable with the the comet by the last week of January 2008! Keep watching this 93 light year distant star, because as regular as clockwork – every 2.867 days – it will drop from magnitude 2.1 to magnitude 3.4 in matter of hours. To calculate Algol’s changes for yourself, try using this great interactive tool provided by Sky & Telescope: The Minima Of Algol. How fun to watch an eclipse that happens on such a regular basis!

But don’t stop watching just yet! While the comet will probably dim to telescope only range by mid-February, it’s going to slide its way past NGC 1342! This small, compressed, open cluster of stars is around 6.5 magnitude and well within binocular and small telescope range. Still not enough? Then hang on as Holmes continues takes a run for the west coast and slides by NGC 1499 – the “California Nebula” around the first week of March! If you’re able to view under very dark skies, the California Nebula can be seen unaided and in binoculars, but its low surface brightness makes it tough for a
telescope. What a great opportunity for astrophotographers!

Isn’t it time to make Perseus your hero?