Amateur Astronomers Alert the World to a Rare Stellar Eruption

Barbara had gone to bed late and really didn’t feel like getting up this morning, but her dog had other ideas. So she reluctantly got out of bed to let the dog out, and like every other clear morning this month, she fired up the telescope and CCD and pointed toward U Scorpii.

When the first image appeared on her computer there was a huge over exposed star right in the middle of the field. Barbara couldn’t believe her eyes. In fact, she didn’t believe her eyes. Just yesterday she had measured U Sco at 18.2V. She quickly took another much shorter exposure, double-checked the position, “and that’s when I started to get excited”, she said.

Dr. Barbara Harris, an amateur astronomer, had been monitoring the recurrent nova, U Sco, for months, in anticipation of a rare eruption that had been predicted by Dr. Bradley Schaefer, an astronomer at Louisiana State University. Barbara and many other observers, participating in a campaign coordinated by the American Association of Variable Star Observers (AAVSO) had begun monitoring U Sco in February 2009. Now on a clear, clam morning in Florida, the moment had arrived!

“Back in December, I had gotten an email from Brad Schaefer, because I had obtained the first image of U Sco as it came out from behind the Sun”, explained Barbara. The image had helped astronomers determine that U Sco had not gone into outburst while it was in conjunction with the Sun. “They were sure that it hadn’t gone into outburst, so he emailed me and thanked me, and said, keep submitting your data to AAVSO, but here’s my home phone number. Call me right away if you get something!”

Barb submitted her observation to AAVSO, looked up Brad’s telephone number, and then thought to herself, “Let me take one more image just to be sure. I don’t want to call him this early and wake him up if I’m not sure.” At this point, it was about 5:30 AM EST. So she took another image, calibrated and measured, removed all doubt from her mind, and called Brad Schaefer.

Just on the other side of Orlando, Shawn Dvorak was just waking up to go to the gym. His telescope had been running all night taking data on several variable stars he was monitoring for AAVSO. Shawn had also begun monitoring U Sco again in January, as it peeked out from behind the Sun. It was usually his last observation in the morning, rising high enough to observe just before dawn.

“I almost didn't observe it this morning since I was planning to go to the gym. I'm glad I did!” Shawn wasn’t quite awake yet, and when the first CCD image came up, he thought to himself, “whoa, I'm pointing at the wrong field, there's no star that bright here”. Shawn said, “Barbara Harris spotted the outburst about an hour earlier but I hadn't heard about it yet, so it was quite a surprise to me when I saw this ‘new’ star”. Thinking the telescope had somehow missed the target; he re-imaged the field to convince himself. He then took a series of shorter exposures, so the erupting 8th magnitude star wouldn’t be saturated on the CCD, and kept taking them for the next fifteen minutes as dawn quickly approached.

About this time, the phone rang in Baton Rouge, Louisiana, and half-awake, Brad Schaefer lifted the phone to his ear. It was Barbara Harris, telling him U Scorpii was in outburst. “ He let out a scream and said thank you, thank you! I’ll start notifying everyone right away”, Barb recalled.

U Sco outburst discovery image: Barbara Harris

Dr. Schaefer has been studying recurrent novae for years, collecting a large database of observations of all the known recurrent novae. His bold prediction that U Sco was going to erupt in 2009.3 plus or minus one year, was the basis for the intensive monitoring campaign by the AAVSO, and was widely publicized as well as published in his recent paper, ‘Comprehensive Photometric Histories of All Known Recurrent Novae’. As U Sco approached conjunction with the Sun in the fall of 2009 and still hadn’t gone into outburst, astronomers everywhere started to get anxious.

When it erupts, U Sco goes from minimum to maximum, then to one magnitude below peak, in under one day. This makes responding to the first sign of an outburst, and pointing large earth and space-based telescopes in time to cover the early parts of an eruption, a daunting task. At 6AM EST, Dr. Schaefer was on the phone and emailing people to notify observatories and space telescopes the moment had finally come.

At 6:15 AM EST, Dr. Matthew Templeton, observing campaign coordinator for the AAVSO, was just stepping out of the shower when he noticed a voice mail on his phone. Before his hair was dry, a confirmation of the outburst from Shawn Dvorak had been submitted to AAVSO. Matt swung into action, and by 6:45 the first ‘AAVSO Special Notice’ had been sent, alerting observers around the world to begin observing the long anticipated eruption of U Sco.

At 1:30 PM, six hours after Barbara Harris had first detected the outburst, the Rossi X-Ray Timing Explorer (RXTE) and the INTREGAL (INTErnational Gamma-Ray Astrophysics Laboratory) satellites were observing U Sco in x-rays and gamma rays. Observations from Hawaii and New Zealand were reported and the international campaign to observe U Sco in outburst had begun in earnest. Over the next several months, astronomers will be monitoring the progress of this outburst at nearly all wavelengths of light from radio waves to X-rays using ground-based telescopes and space-borne observatories.

Dr. Arne Henden, Director of the AAVSO, commented, "This again shows the real advantage of the worldwide distribution of amateur astronomers for detecting transient events like this.  Harris and Dvorak could watch U Sco rise over the Atlantic, hours before professional astronomers in the Western U.S. would have a chance.  Then, because of the winter weather for most U.S. professional observatories, amateurs continued monitoring U Sco from New Zealand and Australia, catching the important first hours of the outburst."

Just think; astronomers may have missed the beginning of the eruption entirely if Shawn had decided to go to the gym, or Barb’s dog hadn’t barked and gotten her out of bed. “My dog has been getting cookies and anything he wants all day”, said Barb.

The progress of the U Scorpii outburst can be followed via the AAVSO, who are maintaining a web page devoted to the event, and anyone can view observational data as they are submitted in real time through the AAVSO website.

For more information on U Scorpii and the AAVSO campaign, please visit
http://www.aavso.org/news/usco.shtml, or contact Dr. Matthew Templeton
at matthewt@aavso.org or via telephone at +1 (617) 354-0484.

U Sco: Long Anticipated Eruption Has Begun

Today, two amateur astronomers from Florida detected a rare outburst of the recurrent nova U Scorpii, which set in motion satellite observations by the Hubble Space Telescope, Swift and Spitzer. The last outburst of U Scorpii occurred in February of 1999. Observers around the planet will now be observing this remarkable system intensely for the next few months trying to unlock the mysteries of white dwarfs, interacting binaries, accretion and the progenitors of Type IA supernovae.

Artists rendition of recurrent nova RS Oph 

Image credit: David Hardy and PPARC

One of the remarkable things about this outburst is it was predicted in advance by Dr. Bradley Schaefer, Louisiana State University, so observers of the American Association of Variable Star Observers (AAVSO) have been closely monitoring the star since last February, waiting to detect the first signs of an eruption. This morning, AAVSO observers, Barbara Harris and Shawn Dvorak sent in notification of the outburst, sending astronomers scrambling to get ‘target of opportunity observations’ from satellites and continuous coverage from ground-based observatories. Time is a critical element, since U Sco is known to reach maximum light and start to fade again in one day.

There are only ten known recurrent novae (RNe). This, coupled with the fact that eruptions may occur only once every 10-100 years, makes observations of this rare phenomenon extremely interesting to astronomers. Recurrent novae are close binary stars where matter is accreting from the secondary star onto the surface of a white dwarf primary. Eventually this material accumulates enough to ignite a thermonuclear explosion that makes the nova eruption. ‘Classical novae’ are systems where only one such eruption has occurred in recorded history. They may indeed have recurrent eruptions, but these may occur thousands or millions of years apart. RNe have recurrence times of 10-100 years.

The difference is thought to be the mass of the white dwarf. The white dwarf must be close to the Chandrasekhar limit, 1.4 times the mass of the Sun. This higher mass makes for a higher surface gravity, which allows a relatively small amount of matter to reach the ignition point for a thermonuclear runaway. White dwarfs in RNe are thought to be roughly 1.2 times solar, or greater. The rate at which mass is accreted onto the white dwarf must be relatively high also. This is the only way to get enough material accumulated onto the white dwarf in such a short time, as compared to classical novae.

Recurrent novae are of particular interest to scientists because they may represent a stage in the evolution of close binary systems on their way to becoming Type IA supernovae. As mass builds up on the white dwarf they may eventually reach the tipping point, the Chandrasekhar limit. Once a white dwarf exceeds this mass it will collapse into a Type IA supernova.

A problem with this theory is the mass that is blown off the white dwarf in the eruption. If more mass is ejected during an eruption than has accreted during the previous interval between eruptions, the white dwarf will not be gaining mass and will not collapse into a Type IA supernovae. Therefore, scientists are eager to obtain all the data they can on these eruptions to determine what is happening with the white dwarf, the mass that is ejected and the rate of accretion.

 Observations from amateur astronomers are requested by the AAVSO. Data from backyard telescopes will be combined with data from mountaintop observatories and space telescopes to help unravel the secrets of these rare systems. AAVSO finder charts with comparison star sequences are available at: http://www.aavso.org/observing/charts/vsp/index.html?pickname=U%20Sco

Kepler Goes Fishing and Reels In Two KOI

By now you've probably heard about the first results from the Kepler mission to find extrasolar planets. Five new exoplanet discoveries were announced recently at the American Astronomical Society meeting in Washington, D.C. Four of the five new planets are larger than Jupiter, about 1.4 times its radius, and they all have orbital periods around their host stars of 3-5 days. Kepler 4b, the oddball of that bunch is about the size of Neptune.

Properties of the first five Kepler exoplanets compared to Earth and Jupiter

All of them are close to their parent stars, so they have high surface temperatures, 1500-1800K or 2240-2780 degrees F. None of this is very surprising. We knew Kepler could detect extrasolar planet transits, and the first ones were liable to be fairly large and close in. These are the easiest to detect in the shortest amount of time.

What is even more interesting to me, is the discovery of two so-called Kepler Objects of Interest (KOI). What is so interesting about KOI?

First, they were discovered because when they disappear behind the parent star from our point of view the light from the system is dimmed dramatically. I mean a lot! Usually this phase is known as the secondary eclipse, and is much less noticeable than the primary eclipse of the star as the planet transits across the face of the star. The fact that the light was dimmed more by the disappearance of the KOI means they are blazing hot and emitting a lot of light on their own. Astronomers estimate the temperature for KOI-74b to be 12250K (21590F) and KOI-81b a blazing 13500K (23840F). The hottest known exoplanet to date is a mild 2300K (3700F) in comparison.

Both KOI are actually hotter than their host stars. KOI-74b companion star is an A1V type star with a surface temperature around 9400K. KOI-81b has a companion type B9-A0V, with a temperature of approximately 10000K.

KOI-74b and KOI-81b are not massive enough to be stars, with solar masses of 0.111 and 0.212 respectively. That's just not massive enough to start nuclear burning in the core. Yet each object is far too hot to only be shining by heat absorbed from its companion star and then re-emitted into space. This may mean they have evolved from hot stars into their current state, and they are slowly cooling with time. The problem with that theory is with host stars that are relatively young type A and B stars, there doesn't appear to have been enough time for these to have evolved from massive, hot stars to the state they are in now.

So what are they? They are the first of what will undoubtedly be a host of newly discovered objects from the Kepler mission. We live in exciting times for astronomy. We are now going fishing with new flies in the tackle box, and we have no idea what other KOI we'll pull out of the next round of data.

Astronomy.FM Every Day-and Friday Night!

From modest beginnings, Astronomy.FM has begun to really gain traction in the online astronomy community. If you haven't heard the buzz you can tune in any time to see what is happening. Astronomy.FM Radio has astronomy related programming running 24 hours a day. Note: the Radio Schedule is in Universal Time.

Some well-known favorites are on the air each week- Astronomy Cast, 365 Days of Astronomy, Are We Alone?, Skepticality, The Naked Scientists, and if you haven't heard Space Pirate Radio! you are missing some real fun.

Friday night at 9PM EST (Sat 02:00UT) I will be on the air LIVE with Marty Kunz on the Event Horizon show. We'll be talking about the AAVSO, variable stars, cataclysmic variables, Citizen Sky, epsilon Aurigae, and whatever else we can squeeze into an hour show. If you miss the live show because you're on a hot date or out at the telescope, the taped show will run every four hours Saturday UT.

I'm looking forward to joining Marty, and I hope you tune it to check out the show. But you don't have to wait until Friday. There is something cool going on at Astronomy.FM all day, every day. Check it out!

Carnival of Space: Nancy Style

This week is a special treat as one of my Internet blogosphere friends is hosting the Carnival of Space #138 on her brand spanking new blog Nancy Atkinson. For those of you who have not had the pleasure of knowing Nancy, she is a class act and a classic over-achiever.

She already has three jobs as Senior Editor for Universe Today, producer for Astronomy Cast, and project manager for the 365 Days of Astronomy podcast. In her spare time she manages to also be a NASA/JPL Solar System Ambassador, as well as dog-catcher, police chief and mayor of her town. She is pretty much everywhere. Rumor has it she has been cloned and is planning to take over the world before 2012. This new blog is just the first step in her mad plan.

Nancy has done a great job of organizing and presenting the material for this week's Carnival. Check it out and stop back later to see what infamous activity this astrono-holic is up to at the new blog 'Nancy Atkinson'.

CBAT Moving!

It looks like the Central Bureau for Astronomical Telegrams (CBAT) will be pulling up stakes and moving to a new home. The CBAT is the official worldwide clearinghouse for new discoveries of comets, novae, supernovae, solar-system satellites, and transient astronomical events. CBAT also establishes priority of discovery (who gets credit for it) and assigns initial designations and names to new objects.

Since 1965, the CBAT has operated at the Harvard-Smithsonian Center for Astrophysics under the umbrella of the Smithsonian Astrophysical Observatory (SAO). According to N. Brickhouse and C. Alcock (SAO), "As of 2010 Feb. 1, the SAO will no longer be hosting the Central Bureau for Astronomical Telegrams (CBAT) for the International Astronomical Union (IAU) because SAO has been unable to obtain sufficient funding to sustain the CBAT financially.  The CBAT is working, with the support of the IAU, on a transition to a new sponsoring institution."

I guess nothing stays the same forever.  It started out in Germany in 1882, moved to Denmark during World War II, then made its way to Harvard in 1965. Right now there is no official word where the CBAT will end up next, but according to IAU General Secretary, Dr. Ian F. Corbett, CBAT "will continue to operate with Dr. Dan Greene as Director, and every effort is being made to ensure no disruption of the CBAT's activities during the transition to its new home".

Will the Real SN 2010O Please Come Forward

This morning's email contained an interesting story about Supernova 2010O. That is just an odd looking name isn't it? SN 2010O, weird.

The naming convention for supernovae is pretty straightforward. At the beginning of each year we roll back the names to the beginning of the alphabet and each supernova discovered is given a name that is the year followed by a capital letter. Thus, the first supernova this year was named SN 2010A, the second one SN 2010B and so on. After they use up the single letters, they begin adding double lower case letters, aa, ab, ac and so on. So SN 2010O was the 15th supernova discovered this year.

According to the Central Bureau for Astronomical Telegrams (CBET) #2143, published January 24, SN2010O was discovered 2".6 east and 1".3 north of the nucleus of the galaxy IC 356.

IC stands for Index Catalogue, which is a catalogue of galaxies, nebulae and star clusters first published in 1895. Since then it has expanded to list 5,387 objects, known as IC objects.

First thing this morning CBET 2144 reports "that a spectrum obtained last night of the purported supernova found in IC 356 (as reported by Dimai on CBET 2143) is in fact the spectrum of a foreground star, not a supernova."

OOPS! I don't recall ever seeing that before. Usually, these things are confirmed as supernovae before being given an official designation. Ah well, nobody's perfect. So what happens when a mistake like this is made?

The IAU can't have a star named with a supernova designation, and they can't skip a letter, no, no! Instead, they have decided to name the next supernova discovered SN2010O, and the lucky winner is...envelope please...(drum roll)...a new discovery from J. Newton and T. Puckett, located at R.A. 11h28m33s.86, Decl. +58o33'51".6, which is 3".7 east and 5".7 north of the center of its apparent host galaxy, NGC 3690.

Supernova 2010O
Image from J. Newton and T. Puckett
Puckett Observatory Supernova Search

Simostronomy on 365 Days of Astronomy

Today's episode of 365 Days of Astronomy is a Simostronomy podcast about the father of variable star astronomy, Friedrich Wilhelm August Argelander. How important is he in the history of astronomy? Well, he has a crater on the moon and an asteroid named after him, and he has four names! What do you think?

Tune in and check it out!

Simopedia: the mad plan

Now that I've had more time to think about it, the plan for Simopedia is coming together. Basically, I'll do an occasional post on a subject and tag it with the Simopedia tag. In the end, I hope to have enough of these 'definitions' to use as reference link outs from blogs on current events or news for terms and ideas previously covered in the Simopedia blogs.

So they serve a few purposes. 1- They can serve as reference, 2- They are still informative, and hopefully interesting enough to read in their own right, 3- They give me topics to write about on days when I have time to write but there aren't necessarily any fascinating or noteworthy stellar astronomy current events or news stories, 4- I'm learning a lot as I discover more about each of the topics, which in turn should make me better at disseminating stellar astronomy information to you, my readers.

For now, I'm still writing about subjects beginning with the letter A. I have a few more I think would be good to include, and then we'll move on to the exciting world of the letter B.

Astrometry

Astrometry is the branch of astronomy concerned with the precise measurements of the positions and movements of stars and other celestial bodies.

Astrometry has been important in history for maritime navigation, since navigators used to calculate their position on Earth upon the observation of stars. (Yes, Jimmy, back in the olden days before GPS satellites!)

Today, astrometry is still important for keeping time. The international time standard is the Coordinated Universal Time (UTC), which is the atomic time synchronized to Earth's rotation by means of exact observations.

Astrometry dates back at least to the Greek astronomer Hipparcos in the 2nd century B.C. He compiled the first catalogue of stars and also invented the brightness scale (magnitude) we still use today.

From 1989 to 1993, the European Space Agency's Hipparcos satellite performed astrometric measurements resulting in a catalogue of positions accurate to 20-30 milliarcseconds for over a million stars.

Modern astrometry was founded by the German mathematician and astronomer, Friedrich Bessel. Bessel was the first to measure the distance to a star as a result of measuring its parallax. He gave the distance to 61 Cygni as 10.3 light years, which is very close to the currently accepted distance of 11.4 light years.

Although once thought of as an esoteric field with little useful application for the future, information obtained by astrometric measurements is now very important in today's research.

Today, astronomers use astrometric techniques for tracking near-Earth objects, and to detect extrasolar planets by measuring the slight wiggle in the parent star's motion on the sky. NASA's planned Space Interferometry Mission will utilize astrometric techniques to detect gas giants around other stars, and perhaps even terrestrial planets nearby.

Argelander

Today I’d like to introduce you to one of the famous historical figures in astronomy, Friedrich Wilhelm August Argelander. You just know he’s important because he has four names! Not only that, the crater Argelander on the Moon and the asteroid 1551 Argelander are named for him.

Argelander was important to astronomy in ways he could never have imagined. A lot of the things we know today, and many of the things we are still seeking answers to, Argelander was already working on in the 19th century. Friedrich Wilhelm August Argelander was a pioneer in astronomy.

Argelander was born March 22nd, 1799 in Memel, which at that time was in the kingdom of Prussia, now Lithuania. His father was a wealthy Finnish merchant and his mother was German. Not a lot is known about his early years, but he eventually came to study under the famous German mathematician and astronomer, Friedrich Bessel, and in 1822 he obtained a PhD at Königsberg University, famous for its School of Mathematics.

Argelander began his professional career in 1820 as an assistant in Bessel's Königsberg Observatory. A few years later, Bessel helped Argelander land a job as director of the Turku observatory in Finland and in 1828 he became professor of astronomy at the university there. Tragically, the observatory, and most of the university buildings, burned down in 1827 and Argelander began the design and construction of a new observatory in Helsinki, where the university was relocated. The new observatory was completed in 1832.

1836 he was appointed professor of astronomy at Bonn, where King Friedrich Wilhelm IV built Argelander an impressive new observatory. As it happens, the king and Argelander were actually old friends. In 1806, following Prussia's defeat by Napoleon, Friedrich Wilhelm, then the crown prince, had sought refuge in the Argelander home in Memel, East Prussia. It pays to have a rich father and friends in high places!

Argelander was very interested in the positions and motions of the stars, and in the direction the Sun and solar system were traveling through the stars. In 1837 he published his first results in a book, "About the Proper Motion of the Solar System", in which Argelander had come to the conclusion that he did not have enough data for the exact answers to his questions. This provided him with the incentive to begin mapping the exact positions of the stars in the Northern sky from 1852 on in Bonn, Germany, a monumental task before the use of photographic plates in astronomy.

Argelander's name is best known for this compilation, called the Bonner Dorchmusterung, the largest and most comprehensive of all the pre-photographic star catalogs. Under Bessel he had begun a survey of the sky from 15°S to 45°N. This was extended at Bonn to an area from 90°N to 2°S and when finally completed eleven years later, in 1863, it listed the positions of 324,198 stars down to ninth magnitude. Again, they did all this work without the use of photography…

Also in 1863, Argelander founded an international organization of astronomers named the Astronomische Gesellschaft, now the second oldest astronomical society after the Royal Astronomical Society.

Being a variable star enthusiast, I became interested in Argelander because he is generally considered the father of variable star astronomy. He was the first astronomer to begin a careful study of variable stars. One of them, epsilon Aurigae, is still a fascinating and challenging mystery to astronomers today.

At the time, only a handful of variables were known, and he was responsible for introducing the modern system of naming them using the capital letters R-Z. It was believed that variability was a rare phenomenon and that this would provide plenty of names for the variables yet to be discovered. In a few years this proved inadequate and the naming system was extended to double letters, and then a numbering system. Today, tens of thousands of variable stars are cataloged, with more being discovered all the time.

Argelander loved the stars, especially variable stars, and was one of the all-time great observers of the heavens. In 1844 he published "An Appeal to the Friends of Astronomy" in ‘Schumacher's Astronomical Year Book.’ This was translated to English and reprinted by Annie Jump Cannon, in Popular Astronomy in 1912.

“Therefore do I lay these hitherto sorely neglected variables most pressingly on the heart of all lovers of the starry heavens. May you become so grateful for the pleasure which has so often rewarded your looking upward, which has constantly been offered you anew, that you will contribute your little mite towards the more exact knowledge of these stars!

May you increase your enjoyment by combining the useful and the pleasant, while you perform an important part towards the increase of human knowledge, and help to investigate the eternal laws which announce in endless distance the almighty power and wisdom of the Creator! Let no one, who feels the desire and the strength to reach this goal, be deterred by the words of this paper.

The observations may seem long and difficult on paper, but are in execution very simple, and may be so modified by each one's individuality as to become his own, and will become so bound up with his own experiences that, unconsciously as it were, they will soon be as essentials.

As elsewhere, so the old saying holds here, "Well begun is half done," and I am thoroughly convinced that whoever carries on these observations for a few weeks, will find so much interest therein that he will never cease. I have one request, which is this, that the observations shall be made known each year. Observations buried in a desk are no observations. Should they be entrusted to me for reduction, or even for publication, I will undertake it with joy and thanks, and will also answer all questions with care and with the greatest pleasure.”

Yea, it’s a little wordy and flowery, but it’s obviously written by someone who loves observing and studying the stars.

The “Argelander Step Method” is a visual method of estimating the magnitude of a variable star. It involves comparing the variable with a comparison star of known constant magnitude, and assigning a step value that reflects the brightness of the variable as distinguished from that of the comparison star. Estimates of the form ‘A(3)V, V(1)B’ are the result, and the magnitude of the variable (V) can be calculated from the known magnitudes of the comparisons (A and B). This is very similar in practice to methods still used today by visual observers of variable stars.

Argelander died February 17th, 1875. But the body of astronomical knowledge that stands on the shoulders of this giant continues today, in the cataloging of the position and motion of the stars within our galaxy, and the study of variable stars, from supernovae and Cepheids used to determine the distances to far away galaxies to the transits of extra solar planets across the faces of stars. In 2006, the three astronomical institutes of the Bonn University were merged and renamed as the Argelander-Institut für Astronomie.

The lunar impact crater Argelander

Carnival of Space #137

This week's Carnival of Space is live over at One Astronomer's Noise.
The Noisy Astronomer, Nicole, is a 4th year graduate student in astronomy, specializing in radio instrumentation.  She believes that an important part of being a scientist is learning how to communicate science to the public, so she gets involved in outreach when she can.

This week's carnival features posts from Astroblog, Martian Chronicles, Kentucky Space, collectSpace, Astropixie, Next Big Future, Habitation Intention, Steve's Astro Corner, Bad Astronomy, Gish Bar Times, We Are All In the Gutter, Spacewriter's Ramblings, Weirdwarp, Road to Endeavor, ChandraBlog, WillGator.com, Cheap Astronomy and the Angry Astronomer. Check it out, go there now.

Double Dipping- Winter 2010

Just to refresh your memory, double dipping is taking in a few deep sky objects while still making variable star observations. Now that winter has arrived, we have a whole new set of deep sky wonders to distract us from our variables. Fortunately, there are plenty of variables within a short star hop of many of your favorite nebulae and clusters. So if you have visitors braving the cold who want to see faint fuzzies, you can still sneak in some variable star observing.

In the last 'double dipping' blog we left off at M33 in Triangulum. Picking up where we left off, we can jump easily from M33 to three of my favorite cataclysmic variables. First, about 2.5 degrees NW of M33 is TY Psc. TY is a UGSU that can get as bright as 11.7V during a superoutburst, but most CV enthusiasts know the field for the distinctive little four-star asterism due south. This grouping provides a convenient mix of magnitudes to use when the star in outburst.

TW Tri is closer to M33, about 1.4 degrees NE of the galaxy. This CV lies in a rather barren part of the sky. It erupts about once a month, making it rewarding to follow its activity. TW is suspected of being a Z Cam type CV, but standstills will have to be verified by CCD observers, since they will probably occur around 15th magnitude or fainter.

While you pretend to hunt for M33 you can zoom over about 1 degree SE of the galaxy and land on the field of TX Tri. Not a particularly active star, I can’t tell you why I still enjoy chasing after it. Maybe it’s because not many of us do. Now scoot back over to M33 and let your guests pretend they can actually see spiral structure in the eyepiece.

Then grab a pair of binoculars and show them the Double Cluster (NGC 869 and 884) in Perseus. RS Per is a red semi-regular variable right smack in the middle of the eastern cluster NGC 884. It varies from about 7.8-10V, so most of the time it can be seen in binoculars. You don’t have to let anyone know you are making a variable star observation while taking in the beauty of the Double Cluster.

Almost 1 degree due west is UV Per. This UGSU gets to 11th magnitude in outburst, but outbursts are few and far between. You may have to wait a year or two for the next one. Fortunately, UV lies in an interesting double string of stars, making this field a pleasure to take in while hunting for an outburst.

The star field around UV Per

TZ Per, an active UGZ, 1.3 degrees NW of the double cluster is another fun, active star you might want to sneak in before the guests get antsy. With outbursts every other week or so, it’s bright more often than not, so it’s often visible in an eight or ten-inch telescope.

M76 is known as the Little Dumbbell Nebula because of its resemblance to M27 in Vulpecula. It also makes a fine place to star hop from to get to KT Per. Slew one degree SW of the faintest Messier object until you find an almost perfect little baseball diamond of 12th and 13th magnitude stars. KT Per is another fine, active CV that gets as bright as 11th magnitude in outburst.

 The Pleiades

On the sky, the Pleiades have always looked to me like they belong to Perseus instead of Taurus. Following the long arm of stars that is the southern part of Perseus, (alpha, delta, nu, epsilon, ksi, then zeta) out to its natural conclusion, you run smack into the Pleiades. This well-known cluster is great in binoculars, small telescopes and large apertures. Even better yet, just about every star you can see is a known or suspected variable. Take your pick.

While we’re in Taurus, slide further south to the Hyades. Just west of Aldebaran is a bright double star consisting of theta 1 and theta 2 Tau. In the same medium power field of view is W Tau, a semi-regular variable that ranges from 8.2-13.0V with a period of approximately 165 days.

The Eskimo Nebula (NGC 2392), in Gemini, is a bright, round planetary nebula that has a fairly remarkable green color to it. Not many deep sky objects exhibit any color at all through modest scopes, but this one always looks green to me. The central star is fairly easy to see, compared to many planetary nebulae. I’ve seen some rings, dark lanes and other features in this planetary on very good nights in the 12-inch, but it takes averted vision and lots of patience to eek out any detail at all. I’d rather be hunting down a few more variables! R, S, T, and U Gem are all within a few degrees of this deep sky favorite. S and T Gem form an equilateral triangle about 1.5 degrees on a side with kappa Gem. Kappa Gem, NGC 2392 form a triangle with U Gem., kappa being about 3.2 degrees north and the Eskimo being about 6 degrees to the west. You can probably get all of them in the FOV of your finder scope. R Gem is a little harder to find, lying a little less than half way from NGC 2392 to epsilon Gem. 6th magnitude 44 Gem is a good sign post for finding R Gem, which lies about 28 arc minutes east.

If your guests have endured the cold night air up to now with you wandering off and doing variable star estimates in between, you can reward them with the “Piesta Resistance” of the winter sky, the Orion Nebula, M42. By all means, do take in this glorious sight. I don’t think anyone ever really gets tired of looking at it. Be happy in the knowledge that a mere 1.6 degrees NW of the center of this mammoth nebula, S Orionis, a very interesting Mira that often exhibits a hump in the ascending branch of its light curve, is waiting for you to stop by for a visit. Varying from 7th to 14th magnitude with a longish period of 415 days, this variable can supply you with a lot of entertaining observing sessions. Plotting the strange behavior of this star on the light curve generator can be fun too. What’s up with the hump? I don’t know, and I don’t think anyone else does either. Imagine that, a mystery that could potentially be solved utilizing amateur data!

The Orion Nebula

When the snow begins to melt, and temperatures start to moderate, the wide, empty portion of the spring night sky will have swung around. The Milky Way hugs the horizon all the way round the sky and anywhere you glance up you’re looking away from the galaxy and out into deep space. We’ll zig-zag through the’ Realm of the Galaxies’ in the spring sky, looking for a few more variable stars in between.

Algol

Algol- Beta Persei, also known as the "Demon Star", is 93 light years away in the constellation of Perseus.

Algol, was the first eclipsing binary to be discovered in 1669 and is the prototypical star of its class. Usually magnitude 2.1 at maximum, it dips to 3.4 every two days, 20 hours and 49 minutes. The entire eclipse lasts about 10 hours and is visible to the naked eye. There is also a secondary eclipse when the brighter star occults the fainter secondary. This secondary eclipse can only be detected photoelectrically.

The light curve of Algol demonstrates the geometry of the system. Eclipsing binaries are among the most important kinds of stars, as they provide us with information on stellar masses and dimensions.

But Algol is equally famed for the "Algol paradox." The less massive star is already a subgiant, and the star with much greater mass is still on the main-sequence. This seems paradoxical because the component stars of any binary are thought to have formed at approximately the same time and should have similar ages. So the more massive star, rather than the less massive one, should have evolved fastest and left the main sequence.

The paradox is resolved by the fact that in many binary stars, material can be exchanged between the two stars, disturbing the normal process of stellar evolution. The originally more massive star will reach the next stage in its evolution despite having lost much of its mass to its companion.

Accretion

Accretion- The term accretion describes the growth of a massive object by gravitationally attracting more matter. This is commonly done through the formation of an accretion disk of gaseous matter. We find accretion disks around smaller stars or stellar remnants in a close binary, or around black holes in the centers of galaxies.

Accretion disks form in non-magnetic cataclysmic variable binaries

Accretion also refers to the collision and sticking of microscopic dust and ice particles in protoplanetary discs and protoplanet systems, leading to planetesimals which gravitationally accrete more small particles and other planetesimals.

Images courtesy Mark A. Garlick

http://www.space-art.co.uk/index.php

Pleas do not use without permission from the artist

Simopedia: A New Simo-series of Blogs

This year I'm starting a new series of blogs called Simopedia. Simply put, I plan to work my way through the alphabet, in no particular order, selecting various stellar topics and categorizing them by letter. Hopefully, in a year or two we will have an alphabet soup of interesting and fun facts- Simopedia.

T Scorpii, Our Long Lost Friend

On May 21, 1860 a nova burst forth in the constellation Scorpius. This nova was notable in the fact that it seemed lie either in or in our direct line of sight with the globular cluster NGC 6093, also known as Messier 80 (M80). At peak brightness it shone at magnitude 7.0, brighter than the rest of the entire cluster. It faded more rapidly than a 'typical' nova and disappeared. The nova was given the variable star designation T Scorpii and hasn't been seen or heard from since.

In recent years, studies of globular clusters have yielded some surprising results, among them a class of stars called 'blue straggler stars'. Blue straggler stars (BSSs) are stars observed to be hotter and bluer than other stars with the same luminosity in their environment. As such, they appear to be much younger than the rest of the stars around them.  This presents a problem for stellar evolution theory, since all the stars in a cluster ae believed to have formed at roughly the same time, so they should all be the same age and have evolved differently mainly (if not only) because of their initial mass.

The three main theories suggested that could produce such stars are: (1) collisions between stars in clusters or (2) mass transfer between, or the merger of components of short-period binaries, or (3) the progenitors of BSSs are formed in primordial triple star systems. Processes such as tidal friction might create very close inner binaries. Angular momentum loss in a magnetized wind or stellar evolution could then lead to the merger of these binaries, or to mass transfer between them, ultimately producing BSSs.

Messier 80
Credit: NOAO/AURA/NSF

Star clusters, both open and globular, are great astrophysical laboratories for astronomers, because all the stars are assumed to be at roughly the same distance and approximately the same age, so differences in the population of stars are assumed to be real, not the result of how far away they are or how old. These blue stragglers are just one hot topic that has caused astronomers to look at clusters like M80 much closer with space telescopes like Chandra and Hubble space telescopes.

Recently, astronomers studying stellar populations in M80 in the ultraviolet, using the HST, were able to identify most of the known x-ray sources in the core of the cluster. While the main point of their investigation was to study the populations of BSS's, one of these sources happened to be a dwarf nova in outburst at the time of the observations. More interesting than that, it appears to be consistent with the location of the 1860 nova, T Scorpii. Given its position, X-ray and UV brightness and variability, this source is almost certainly the true counterpart to T Sco. After 150 years we have finally found an old friend.

Welcome back, T Scorpii.

T Pyxidis: The Story That Just Won't Die

Normally I wouldn't do this, but this story has propagated itself so widely through the internet and blogosphere I feel I have to chime in, if for no other reason than to help set the record straight. So what you are about to read is a story about a Tweet about a blog, about a blog, about the other blog, about several news articles, about a press release, about a research paper about...a variable star.

Artists image of the recurrent nova RS Oph

Credit: David Hardy/PPARC

It all started last week when Edward Sion and his team from Villanova announced results of research they had done on the recurrent nova, T Pyxidis. Among other things, they claimed this recurrent nova may be at or near the tipping point in its evolution, and that it will someday (soon) become a supernova. They also re-estimated the distance to T Pyx as being much closer than thought before, approximately 3300 light years distant. Then the misinformation bomb was dropped, as the last bit of their press release states:

"...gamma radiation emitted by the supernova would fry the Earth, dumping as much gamma radiation (~100,000 erg/square centimeter) into our planet, which is equivalent to the gamma ray input of 1000 solar flares simultaneously."

Even though these claims were disputed at the press conference by other supernovae experts in attendance, namely Alex Filippenko, the genie was out of the bottle and before you could say, "Wait, you don't understand!", the popular press was claiming the end of the world was near.

The Daily Telegraph ran with the headline Earth 'to be wiped out' by supernova explosion, The Sun ran The death star, and bloggers began trying to undo the damage. Unfortunately, they managed to splurt out some erroneous or misleading information of their own.

First, let me begin by saying, astronomers do not really know for sure what the progenitors of supernovae explosions are. We have some very convincing arguments and theories, but there are still entire astronomical conferences held on this subject each year, presenting differing points of view based on new observations and models.

The main reason they are so interesting to astronomers is because type 1A supernovae are used as standard candles to determine the distances to galaxies too far away to estimate their distance any other way. All of our theories on the history and future of the Universe are based largely on measurements of galaxies at high redshifts. The whole theory of the acceleration of the expansion of space is based on galaxies not behaving as predicted, based on measurements of distance based on...you guessed it, type 1A supernovae measurements.

The connection between supernovae and recurrent novae is not firmly established. Yes, they MAY be part of the population of progenitor systems that eventually become supernovae, but we don't know this for sure. If they are, well that makes them a much more interesting type of variable star, which also makes it easier to obtain observing time on a space telescope, or a grant to do research on them. So for those studying recurrent novae this is a convenient connection to try to make. After all, refining the cosmological distance scale and the expansion of the Universe, and how that relates to dark matter and dark energy are some of the hot, sexy topics in astronomical research these days.

Claiming a supernova could release as much gamma radiation as Scion and colleagues claimed is factually incorrect. Phil Plait does an excellent job of explaining the relative damages a supernova or a gamma-ray burst in our galaxy could do to the Earth in his book 'Death From the Skies', and a supernova explosion at that distance has no chance of damaging our planet.

Unfortunately, Phil did manage to get some of the facts about recurrent novae wrong in his blog rebuffing Scion's claims when he wrote, "Lots of recurrent novae are known, and are fairly well understood."

Not exactly. The currently known recurrent novae are T Pyx, IM Nor, CI Aql, V2487 Oph, U Sco, V394 CrA, T CrB, RS Oph, V745 Sco, and V3890 Sgr. That is only ten stars. Out of the billions of stars in our galaxy, thousands of known cataclysmic variables and hundreds of known galactic novae, ten are known to be recurrent novae. Recurrent novae, like R CrB type stars are actually quite a rare phenomena, as far as we know.

If they were fairly well understood, the definitive paper to date on the subject of their history and behavior, Comprehensive Photometric Histories of All Known Galactic Recurrent Novae by Bradley E. Schaefer, would not still be asking at its heart: What is the death rate of RNe in our galaxy, are the white dwarfs gaining or losing mass over each eruption cycle, and whether or not RNe can be the progenitors of Type Ia supernovae.

Given a little time to reconsider what he wrote, I'm sure Phil would change that sentence. On the other hand, I have to give him credit for coining one of 2010's leading candidates for 'best skeptical science phrase' when he came up with "disaster-porn".

"There was no need to disaster-porn this release up the way it was done. Recurrent novae and Type Ia supernovae are fascinating, well worth our attention for any number of reasons including of course their potential danger."

My friend, Ian O'Neill, has commented on this situation also, on the Discovery Space News and AstroEngine.

The last bit of misinformation that really needs to be adrressed before leaving this subject, is the notion that any of this will happen any time soon. The title of the press release, "The long overdue recurrent nova T Pyxidis: soon to be a Type 1A supernova", was as misleading as the facts presented.

Soon on human, everyday-guy-on-the-street terms, means this week or this year. When astronomers use the word 'soon' or the phrase 'in a short time' they can and do usually mean tens of thousands or millions of years. Not much at all happens soon with recurrent novae, that is one of the reasons we know so little about them. Recurrent nova eruptions happen on human time scales of decades or possibly once per 100 years. To astronomers these are relatively short time scales, as compared to the thousands or millions of years between classical nova eruptions or the billions of years it takes for most stars to evolve and show any change at all. But that means that since we've been paying attention and monitoring the sky with cameras and telescopes keeping records, we've only seen these recurrent novae go into outburst a few times in history.

In fact, if you now the story of T Pyx, you know that one of the things that makes it interesting is the fact that it is overdue for a recurrent novae outburst. If it had kept to its usual pattern it would have already erupted some time ago. But if you read the Schaefer paper, he explains that T Pyx is actually evolving into a new type system and may not erupt again for hundreds of years, and "soon" won't be a recurrent nova at all.

"We now realize that what has happened is that the T Pyx accretion rate dropped substantially soon after the time of the last eruption, so it will be a long time until the next eruption (Schaefer 2005). Indeed, a more detailed accounting that includes the recent declines since 2005 plus the associated larger trigger mass implies that T Pyx won’t erupt for many centuries (Schaefer et al. 2009). Also, with the likely continuing decline in accretion, T Pyx will soon be going into hibernation, and thus will not suffer any further RN events for almost a million years (Schaefer et al. 2009). That is, T Pyx has stopped being a recurrent nova."

Recurrent novae are rare and beautiful beasts in the cataclysmic variable zoo. Their eruptions and behavior are interesting enough to garner our attention. There really is no need to "disaster-porn" their stories to make them interesting to the astronomical community or the public.

Brad Schaefer is a very enthusiastic and engaging speaker. If you haven't heard this before, check out my interview with him on Slacker Astronomy where we talk about recurrent novae, and T Pyx.

Carnival of Space #136: Simostronomy Edition

Ladies and Gentlemen, come on in and experience the fantastical, the sensational, dare I say cosmological and explorational, Carnival of Space, Number One Hundred Thirty-Six!

We'll take you to the Moon, we'll fly through the stars, we'll go visit a friend on the surface of Mars.
So scroll down the page, see what there is to see, the tickets are priced just right..they're FREE!

First we will take you to the Moon...

Out of the Cradle has an excellent interview with a Russian team scientists working on sending a rover to the Moon as part of the Lunar X Prize contest. The prize will award US$20 million to the first team to land a robot on the moon that successfully travels more than 500 meters and transmits back high definition images and video.

Collect Space has an interesting story of Moon rocks that have come to Earth from the Moon, traveled to the peak of Mt. Everest and will now end up in a plaque on the space station. Talk about a ride!

Venturing further out into the Solar System...

Cumbrian Sky takes us to the surface of Mars to visit the Spirit rover. The rover has been on Mars for six years, so this blog is nice retrospective on what has happened in that time.

Gish Bar Times introduces a series of articles over five days covering various topics related to the discovery of the Galilean moons.

The Angry Astronomer blogs about a new, refined age of the solar system. It's not polite to ask a solar system how old she is, but the Angry Astronomer knows.

Some of the most popular rides in the Carnival these days are rides to planets around other stars, known as extrasolar planets or exoplanets. Phil Plait (pictured here), at the Bad Astronomy blog writes about a potential way future scientists could detect water on planets by catching glints off the surfaces of lakes or oceans.

The Slacker Astronomy podcast interviews Steve Howell, one of the Kepler mission scientists about the potential to discover asteroids around white dwarfs. There is also some light-hearted discussion of Ophiuchus, the orphan astrological sign.

Next we venture out among the stars...

Some of the biggest stellar news came from the AAS meeting in Washington, DC. The recurrent nova T Pyxidis made headlines when astronomers claimed it may go supernova soon and endanger the planet Earth!

Thankfully, cooler heads prevailed and the blogosphere helped to clear up misinformation spread by the print and news media.

Next Big Future takes on the story published on Astronomy.com that states,"If a type Ia supernova explosion occurs within 1,000 parsecs (3,260 light-years) of Earth, then the gamma radiation emitted by the supernova would fry Earth, dumping as much gamma radiation (about 100,000 ergs per square centimeter) into our planet, which is equivalent to the gamma-ray input of 1,000 solar flares simultaneously. The production of nitrous oxides in Earth's atmosphere by the supernova's gamma rays would completely destroy the ozone layer if the supernova went off within 1,000 parsecs."

Ian O'Neill at Discovery News Space points out several more articles published on the web creating unnecessary panic about T Pyx and the likelihood of a disaster on Earth caused from a supernova 3,260 light-years from us.

Ian writes, "So, where's the panic? That's right, there isn't any...(snip)
Meetings like the AAS are key to the scientific process where theories are aired and results are open to academic scrutiny, sometimes it's better to wait until after the conference before reaching any conclusions."

The Simostronomy contribution for the week talks about astronomers riding the waves of stars through asteroseismology. Stellar surfing, now there's a carnival ride to try out.

Starry Critters takes us on a ride to the edges of time through the newest Hubble Space Telescope image of faint galaxies at the edge of the universe. The unique image viewer on this page is worth taking time to play with. This ride will have some of the longest lines at the carnival this week!

The carnival also features a time machine ride this week! If we can only see distant objects as they appeared in the past, how do we know how far away they are now? Cheap Astronomy explains time and distance on this episode of 365 Days of Astronomy.

Centauri Dreams, the blog about exploring the ways man will actually go to the stars, says one way we can go is to hitch a ride on a "cycler".  We might use 'orbital cyclers' to get us around the solar system, or 'interstellar cyclers' to help us reach the stars, if we can just figure out how to push that much mass up to speeds approaching that of light.

Speaking of the speed of light, Nancy Atkinson of Universe Today takes us on a ride through the carnival fun house with a faster than light pulsar phenomena that will bend your mind just a bit. Nancy assures us that no laws were broken in the process.

If there are to be laws in space, governed by some sort of moral code of behavior, Habitation Intention provides a place to start with the 10 Commandments of Space Habitation.

Riding bravely into the future, Next Big Future discusses the possibility of ultra-dense deuterium. If it is shown to be stable long enough, it could be as important as the discovery of nuclear fission.

My thanks to Fraser Cain at Universe Today for organizing the carnival and many thanks to the bloggers who gave us a ride through the solar system, stars, time and the cosmos. I hope you enjoyed the Carnival of Space this week, thank you for stopping in.

Telescopic LPVs for New Visual Observers

Okay, so you’ve been observing some naked eye and binocular variables for a while. Good for you! The stars in the AAVSO Ten Star Training Program can be fun and rewarding to observe for a lifetime.

Maybe you were drawn in by the Citizen Sky project and now you’re getting hooked on variable stars. Hey, it happens; you are not alone. But epsilon Aurigae is in full eclipse now, and will remain faint for most of this year, so maybe you’re ready for some new stars to satisfy your new addiction.

Perhaps you already owned a telescope or you finally got that shiny new 8” Schmidt-Cassegrain you’ve had your eye on for Christmas. Now where do you look for interesting variables? I’ve got some suggestions for you. These are fun stars to observe, AAVSO still needs observations of these stars, and best of all, they are easy to find and identify, so you won’t spend cold winter nights looking for them. You can spend your time observing them instead!

R Aur- After you make your observation of epsilon Aurigae for the night, (because you should keep observing it all the way to the end of the epsilon Aur campaign!) use your telescope and finder to star hop over to this great long period variable. I think of this one as the ‘Pirate Star’, because its name is “Arr, Arr!”

There are plenty of magnitude 6 to 9 stars in the area to help point the way, making this one easy to find. Varying from 6.9-13.9V, it also happens to be an interesting double star! R Aur is on the rise from minimum right now, so it will get easier as winter turns to spring.

R Cas- This Mira gets as bright as 4.7, and can fade to 13.5. R Cas is currently on the rise from around 10th magnitude so it will be easy to observe all winter.

T Cas- When at or near maximum, this is one of the reddest stars you’ll ever see in the eyepiece. This Mira varies from 6.9-13.0V and has a very interesting light curve with multiple humps, perhaps indicating multiple periods. Currently around 9th magnitude, but is it rising or fading? Have fun following this one!

T Cas has humps like a camel in its light curve. What's up with that?

V Cas- This Mira has a pretty regular period of 228 days. Ranging from 6.9-13.4, V Cas is currently at minimum, so it will become easier to observe as winter progresses and it brightens.

S Per- Sitting in a beautiful star field with plenty of 8th and 9th magnitude stars to point the way, this interesting semi-regular variable, varying from 7.9-12V, is somewhat unpredictable, so you never know what it will be doing next time you observe it.

W Tau- Located in the Hyades, just west of Aldebaran is a bright double star consisting of theta 1 and theta 2 Tau. In the same medium power field of view is W Tau, a semi-regular variable that ranges from 8.2-13.0V. The period is listed as approximately 165 days, but this star is unpredictable, and the light curve for the last 1200 days is chaotic. This, plus the fact it is easy to find and observe, makes W Tauri a fine catch on a cold winter night.

W Tau is close to a beautiful double star in the Hyades cluster. You gotta be able to find this one!

There you go; a half dozen stars to add to your variable star program. If you’re looking for more you can check out the Stars Easy to Observe list on the AAVSO website at http://www.aavso.org/easy-stars

If you run into trouble, or just want some friendly advice from an experienced observer, contact me at mikesimonsen at aavso dot org. I coordinate the AAVSO Mentor Program and I can hook you up with one of our great mentors to help give you a boost up the learning curve.

Impressions from the 215th AAS Meeting in Washington, DC

The American Astronomical Society held its 215th annual meeting in Washington DC January 3-7. Now with the talks all done, the posters taken down and the tables and chairs packed away, I thought I’d give a brief overview of my own impressions from the meeting.

I think everyone who went to the meeting was eagerly anticipating the first results from the Kepler mission. They did not disappoint. Five new exoplanets, a mysterious, possibly new type of object too hot to be a planet, but not a star, (or is it?), reports on the excellent performance of the detectors and space craft, and asteroseismological results, all from the first months of observations.

"Kepler is working so amazingly well," says Berkeley's Geoff Marcy, a member of the Kepler science team, "that the light curves look like they come from a textbook, not a real instrument."

What I found even more impressive was the immediate release of science papers by the team, with a dozen significant papers hitting the astro-ph server within hours of being announced at the AAS meeting. The mission scientists were ready and loaded for bear right out of the shoot. We are gong to be hearing about results from this exciting mission for years and years.

The Hubble Space Telescope is in good hands. Dr. John M. Grunsfeld was appointed Deputy Director of the Space Telescope Science Institute (STScI) in Baltimore, Md. on January 4th. STScI is the science operations center for NASA's Hubble Space Telescope and the James Webb Space Telescope planned for launch in 2014.

If John’s name sounds familiar it’s because he’s a veteran of five space flights, including three servicing missions to the Hubble. He’s logged over 835 hours in space, including eight space walks, totaling nearly 60 hours. He succeeds Dr. Michael Hauser, who stepped down in October.

There were plenty of new science results presented at AAS demonstrating that Hubble has been reborn again, and is in fact better than ever. Images of the earliest galaxies ever recorded were among the hot Hubble news this week. "We're just at the beginning of this story," said Grunsfeld. "It's incredibly thrilling to see these new instruments working and delivering results."

One of my favorite 2009-2010 stories is the enigmatic variable star epsilon Aurigae. Epsilon Aur made the news at AAS on several fronts. Talks from some of my colleagues on results from the Citizen Sky project were given on Tuesday, and results from observations in the far ultra-violet using the Spitzer Space Telescope were also big news.

Observations by Dr. Don Hoard and collaborators using Spitzer revealed the presence of a disk about 8 astronomical units in diameter, as expected. What was unexpected was that it consists of relatively large particles mostly the size of sand grains, not the usual microscopically fine space dust. Observations also indicate the presence of a smaller, very hot star at the center of the disk, probably spectral type B.

Hoard and his colleagues have proposed a new model to explain these observations. A key element is that the primary, a bright F supergiant, is much less massive than previously thought. In their model the primary started off at around 10 solar masses (as opposed to the 15 or 20 previously assumed) and has since blown off much of that via its stellar wind. The B star companion has only about 6 solar masses, and shines much dimmer. According to Hoard and colleagues, the dark disk is not that of a newborn star still accreting material. The disk is made of material that the B star gravitationally captured from the evolved primary’s wind.

"It was amazing how everything fell into place so neatly," said collaborator Steve Howell of the National Optical Astronomy Observatory. "All the features of this system are interlinked, so if you tinker with one, you have to change another. It's been hard to get everything to fall together perfectly until now."

There is some controversy about this and still a lot to be learned. Arne Henden, director of the American Association of Variable Star Observers, (and my boss), emphasizes that the mystery of epsilon Aurigae has not been solved yet. “We’re nearing the middle of the eclipse, and lots of interesting things will happen over the next year. There are still things about this system we don’t understand.”

The blogosphere was alive and kicking throughout the meeting. New media coverage of the fast breaking news was phenomenal. First and foremost, I have to thank and congratulate Pamela Gay and Fraser Cain for the excellent coverage of the press conferences and many of the invited talks on Astronomy Cast Live. I wasn’t able to attend the meeting, but thanks to the live coverage I feel like I got to see a lot of the events I would have wanted to cover if I was there in the flesh. I was able to watch new NASA Deputy Director, John Grunsfeld, live and share in the audience’s approval and excitement. The 21st century will see a lot more remote coverage of science news, and Astronomy Cast Live is showing the way.

Twitter was also abuzz with tweets coming directly from attendees. There was a wave of tweets rolling in as Charlie Bolden, the new NADSA administrator, gave the keynote address to a packed house. Every time he made an applause-worthy or controversial statement, Twitter lit up with quotes and comments from people in the conference room.

Bloggers from Universe Today and elsewhere covered all the big stories and had blogs posted by the end of the day on everything exciting and new.

The print press was also there in full force. I have to admit, Bob Naeye, the Editor in Chief of Sky and Telescope magazine impressed me at the press conferences with his knowledgeable and penetrating questions. He appeared well versed in what ever the topic of the moment was, from Gamma-Ray Bursts to stellar evolution to exoplanet searches and results. Bob was everywhere, asking multiple questions of numerous speakers at just about every press conference I witnessed.

By and large, scientists are doing better than ever at getting the word out about the scientific method, the universe we live in and the ‘secret lives of astronomers’. There are still those PhDs who can’t give a presentation, and should take a public speaking 101 course, but every discipline has people who just suck in front of a microphone. I give a big Simo-wag-of-the-finger to those astronomers who come ill prepared to give a talk or stammer through press conferences; you know who you are. Fortunately, they are the small minority.

I think the 3,000 people attending this meeting would agree that most of these astronomers are succeeding admirably informing the public and each other in entertaining and enlightening ways. The AAS is not a bunch of geeky nerds with pocket protectors in lab coats. They are real people doing real science in the real world, really well. Really!