Volume XX No. 5 January 2009 What's Inside… Stewart's Skybox Pg 4 General Meeting Pg 7 PowerPoint Class Pg 7 Contacts Pg 8 Theater in the Sky Pg 9 Note: Use bookmark panel in Adobe Reader. "What Did Tycho Brahe See?" By Clif Ashcraft as told to Ray Shapp Echoes from Tycho's Supernova You may have seen the news release from the Suburu research team about their images of the reflection nebula taken on September 2 and 24 in 2008 with the Subaru telescope on Mauna Kea: http://subarutelescope.org/Pressrelease/2008/12/03/index.html Amazingly, the Subaru Telescope went back in time and observed light from a "new star" that originally was seen on November 11, 1572 by astronomer Tycho Brahe and others. The Subaru team presented their results in a pair of monochrome images of "light echoes" which are reflections of light from the original supernova blast that have bounced back to Earth from interstellar dust clouds. Here below are the monochrome pictures of the light echoes taken on September 2 and 24, 2008. Even with careful comparison between the two pictures, it is hard to visualize how far the light had traveled in 22 days. Clif's clever solution to this problem was to colorize the September 2nd image red, and the September 24th im- age blue, and then overlay the two images. Clif's overlay is shown further below. The composite image shows the displacement of the reflections quite dramatically. Note that the nebulosity around the star cluster in the lower right is red only, and the diffuse nebula in the upper left is cyan only, with the nebulosity in the center being illuminated both days but with an obvious offset. I expect that this region has nebulosity extending along our line of sight with the closer part illuminated on September 2nd and the more dis-tant part on 24th. The direction of light travel is opposite from the direction indicated by the arrow which is point-ing towards the supernova remnant. The image is about 140 arc seconds square. The thin wavefront of radia-tion is only a few light days in thickness. Radiated light from the supernova behind the wavefront has decayed to the point that its reflection is no longer visible to the Subaru telescope. (continued next page) More Echoes (continued from previous page) The cloud of nebulosity has a complex shape, extending much further away along our line of sight as well as back toward us. Because of this, the closer portions are lit up by the wavefront on the 2nd as it is also illuminating the lower right nebula. The farther portions are being illuminated when the nebula in the upper left is lit up on the 22nd. Note that these nebulae have nothing whatsoever to do with Tycho's supernova. They were just lying out there waiting for the wavefront to come along. If you look up the Palomar Schmidt plates for the same location using the Aladin Interactive Sky Atlas ( http://aladin.u-strasbg.fr/ ) as seen in 1960 or so, you would not see any of the nebulae because they are too far from any bright stars to be visible to us. In fact, images taken by Subaru six months ago probably don't show the nebulae either, however, if we look around the sky with sensitive tele-scopes, other nebulae will probably send echoes back to us when the wavefront passes them. The geometry of the echoes observed by the Subaru team is illustrated by the figure above based upon the assumption that the distance to the supernova remnant is exactly 4500 parsecs ( Reynoso et al, The Astronomi-cal Journal, 117:1827-1833, 1999 April, http://tinyurl.com/84zcuo ). There is some uncertainty to this figure, and somewhat different dates and distances in light years would result if a different distance were assumed. The surface of the ellipsoid formed by rotating the green ellipse about the line of sight to the supernova defines the locations of all possible nebulae from which echoes of Tycho's supernova would have been visible in 2008 if only someone were looking for them with a sufficiently sensitive telescope. As time passes and the wavefront from the supernova explosion continues to expand, successively larger ellipsoids describe the locations from which echoes could be seen in the future. Tycho Saw a Type Ia Supernova Using the Faint Object Camera and Spectrograph (FOCAS) instrument at Subaru, the light echoes showed clear absorption of once-ionized silicon and absence of the hydrogen H-? emission. This evidence allowed the Subaru team to identify the original blast as that of a Type Ia supernova. I think this may be as close to a time machine as we are likely to get, at least in this generation. Stewart's Skybox by Stewart Meyers January 2009 is the start of the International Year of Astronomy (IYA). So, this article will discuss what the IYA means, what activities are planned, and more importantly, what you can do to help this cause. Why IYA? T he United Nations (UN) declared 2009 the International Year of Astronomy. The idea of the UN setting aside a year to honor a topic is not new. Most of the time, when the UN makes one of those resolutions, it is usually something like declaring 2008 World Hunger Year - something in support of some charitable cause that gets hardly any notice outside of the UN building. The idea of a year devoted to a specific aspect of science is not new either. Various international scientific organizations have proposed recognition years focused on some specific aspect of science. The most famous of these declarations occurred when the International Council of Scientific Unions (ICSU) declared an 18-month period from July 1957 to December 1958 as the International Geophysical Year (IGY). Among its many accomplishments, the IGY gave the scientific pretext for the United States and the Soviet Union to pursue satellite programs, hence launching the Space Age. Now, for the first time, the International Astronomical Union (IAU) and the UN have joined forces in creating the IYA. Unlike the IGY, this yearlong event is focused on educating the public as opposed to scientific re- search. Picture It, Italy, 1609 The idea for the IYA had its start in 2005 when Italian astronomer Franco Pacini realized that 2009 marked the 400th anniversary of the first use of a telescope for astronomical purposes. Pacini thought it would be a good idea to do something to honor Galileo's noteworthy achievement. Pacini presented the idea to the International Astronomical Union (IAU), which approved it in 2006. Figuring this event was deserving of much wider recognition, the idea of the IYA was pitched to the UN through the United Nations Educational, Scientific, and Cultural Organization (UNESCO). In a rare show of support for astronomy by a governmental body, the UN General Assembly issued the official IYA declaration in 2007. The U.S. House of Representatives endorsed it in 2008, thereby officially showing American support. With the political details out of the way, the IAU got down to actually organizing the IYA and planning its events and goals. As expected from the IAU, the IYA is a bit bureaucratic in its organization. The IAU directly handles the main details of the IYA and the main online headquarters for the IYA is at http://www.astronomy2009.org. Then, there are the National Nodes, one for each of the 130 countries taking part in the IYA. The American node is at http://www.astronomy2009.us The Eleven Cornerstones The main official emphasis of the IYA is on what are called Cornerstone Activities. These cover a wide range, from observational activities, addressing social issues, and even a bit of merchandising. Here is the list: 1. 100 Hours of Astronomy - 400 Years in the Making: This activity runs from April 2nd to April 5th and will feature back-to-back webcasts from major observatories and other astronomical institutions, as well as public observing sessions throughout the world. 2. The Galileoscope: Technically, this is not an activity, but a piece of merchandising associated with the IYA. It is a small telescope with capabilities similar (probably slightly superior) to the telescope used by Galileo but constructed with modern materials. This instrument is expected to sell for some-where between $10-$15 in the United States, and probably a similar price in other countries. The purpose of the Galileoscope is to offer a low-cost way for kids and others to discover astronomical observation. 3. Cosmic Diary - Life of an Astronomer: Professional astronomers will become bloggers as they post online accounts of their work. These blogs will be accessible through the IYA websites. Later in 2009, highlights of these blogs will be published in book form. 4. Portal to the Universe: No, this has no connection with the upcoming "Stargate" spin-off series, but rather it is a planned website that aims to become the ultimate astronomy site on the Web. It will fea-ture news from all aspects of astronomy and it will also offer social networking capability. 5. She is an Astronomer: This is being handled primarily through the UN as part of its Millennium De-velopment project and is a website devoted to gender issues in astronomy (i.e. wage equality, job opportunities, etc.). 6. Dark Sky Awareness: - Seeing in the Dark: Light pollution will be the focus of this activity, and it includes the two major global star count projects, the Globe at Night project in March and the Great Worldwide Star Count in October. 7. Astronomy and World Heritage - Universal Treasures: A campaign to select and preserve sites of astronomical significance. 8. Galileo Teacher Training Program: This is a program that will alert schools and teachers to astron-omy education content and resources found online. 9. Universe Awareness - One Place in the Cosmos: One of the more "politically-correct" activities, this involves exposing underprivileged children to astronomy and it also delves into the multicultural aspects of the science. 10. From Earth to the Universe - The Beauty of Science: No, this is not a Tom Hanks HBO miniser-ies, but a program to encourage the posting of astronomical imagery and artwork in non-traditional settings, such as shopping malls, transit stations, and other places. 11. Developing Astronomy Globally - Astronomy for All: This program is geared to improving as-tronomy training and science in general in developing countries and other countries that lack strong backgrounds in astronomy. Naturally, the activities of the IYA are not limited to the 11 Cornerstones. There are other activities as well. A listing of some suggested activities are at the national IYA node. Even these are not etched in stone and can be adapted to meet local circumstances. Some of the listed activities include a "telescope amnesty program" which reconditions old unused telescopes. Another activity is sidewalk astronomy. The Others As one would expect, a number of organizations are involved in this massive project. NASA is a major player and has even set up its own website in support of the IYA ( http://astronomy2009.nasa.gov ), and is also supporting it through the Night Sky Network which is a joint venture between NASA's Jet Propulsion Labora-tory and the Astronomical Society of the Pacific. Even major observatories are getting involved. For example the National Optical Astronomy Observatory (NOAO) is playing a very prominent role in the plans for the IYA in the United States. Even the National Radio Astronomy Observatory (NRAO) is getting involved with a "quiet sky" campaign in conjunction with the Dark Sky Awareness activities. Amateur organizations are not sitting on the sidelines for the IYA. The American Association of Variable Star Observers (AAVSO) is setting up a program to introduce people to variable star observing by having them fol-low the dimming of Epsilon Aurigae. Other major amateur organizations taking part in the IYA are the Associa-tion of Lunar and Planetary Observers (ALPO) and the Astronomical League. Of course, many astronomy clubs (hopefully all of them before too long) will be doing their thing to honor this great international occasion. The New Technology The people in charge of the IYA have decided to fully to embrace lots of new technology in order to get the message out to the public. One of these innovative approaches is Astronomy Isle, a section of the Second Life ( http://astronomy2009.us/newmedia/second-life/ ) online virtual community devoted to astronomy and space science. Another area of new technology being harnessed in the service of the IYA is podcasting. For those who are not technologically inclined, a podcast is an audio file (usually in the mp3 format) that is just like a radio show except that it is posted online for people to download and listen to. There is a site called 365 Days of Astron-omy ( http://365daysofastronomy.org ) that aims to have a podcast for every day of 2009. As of this writing, only a few days in January have been booked. Even the latest craze in online text messaging is getting involved. AstroTwitter ( http://astronomy2009.us/newmedia/astrotwitter/ ) is the IYA's program to use the popular Twitter service to send short astronomical text messages to astronomers and others. And the IYA is even getting into a small-scale version of the remote computer controlled telescope act. The Harvard Center for Astrophysics is operating the MicroObservatory network ( http://mo- www.cfa.harvard.edu/microobs/guestobserverportal/ ). This is a small network consisting of five different in-struments that can be accessed online. The user selects which telescope he or she wants to use, then chooses which object they want to image from a list. After setting the parameters, the observation is made and the resulting image is emailed to the user. Ask Not What the IYA Can Do for You… While the roster of astronomical organizations supporting the IYA is impressive, and the use of Internet tech-nology is clever and innovative, the success of the IYA depends on the involvement of amateurs. So here are some suggestions of what you can do for the IYA. One very obvious suggestion is simply get the word out. Many people will miss the message from the UN and even fewer will hear it from the IAU, so we amateurs are absolutely vital to let people know about the IYA. Don't be afraid to promote the IYA outside of the club. The more people who know about the IYA events, the better. Also, if you have any connections with influential people, members of the mainstream media, or others of the group that James Burke refers to as "the Great and the Good", plug the IYA to them and try to get them inter-ested. They can be very helpful in getting the word out. Who knows? Maybe some might even offer their ser-vices to the IYA cause. Support the club's IYA activities. Volunteer to help out in any capacity. We can use all the help we can get. Like the old saying goes, many hands make light work. Finally, when it comes to suggestions for IYA activities, think outside the box. As many of us are well aware, getting members of the public to attend lectures, star parties, and observatory open houses can be quite chal-lenging. If we want to get the public interested and show up at our events, we need innovative ideas. If you have any, don't be shy. Let us know. The IYA promises to be one of the biggest things to happen in the world of amateur astronomy. It is a ven-ture involving the IAU, UN, and the biggest names in the field of astronomy, and it will utilize lots of modern high technology. But it also involves amateurs like you and me. And it is the amateur community that will play a vital role in any success the IYA has. It is all up to you. Get out there and help any way you can. GENERAL MEMBERSHIP MEETING JANUARY 16, 2009 "The Evolution of Galaxies in Different Environments" Dr. Jacqueline van Gorkom, Columbia University Since 1988, Dr. van Gorkom and her students at Columbia University have studied the evolution of galaxies in a variety of radio, optical, ultraviolet and infrared telescopes. She will discuss her work exploring the many aspects of gas and galaxy evolution by observing the 21cm neutral hydrogen line. She received her Ph.D. in the Netherlands using the Westerbork Radio Synthesis Telescope, which was one of the first of its kind. She has been interested in radio astronomy ever since, even moving to New Mexico where the Very Large Array radio telescope had just become operational. She then moved to Manhattan, where she has been a professor at Columbia University. 8 pm in the ROY SMITH THEATER EMAIL CONTACTS presi-dent@asterism.org President of AAI editor@asterism.org Editor of The Aster-ism Ray Shapp, Editor Deadline for submissions to each month's newsletter is the first Friday of that month. member-ship@asterism.org AAI Membership Chair trustees@asterism.org All three Trustees of AAI ray@asterism.org Ray Shapp for the website exec@asterism.org Executive Committee plus Trustees QOs@asterism.org All Qualified Observers Info@asterism.org AAI president, corresponding secretary, and computer services chair research@asterism.org Research Committee technical@asterism.org Technical Committee MEMBERSHIP DUES Regular Membership: $21 Sustaining Member-ship: $31 Sponsoring Member- ship: $46 Family Membership: $5 First Time Ap-plication Fee: $3 Sky & Telescope: $32.95 Astronomy subscription: $34 (Subscription renewals to S&T can be done directly. See "Membrship-Dues" on website for details.) AAI Dues can be paid in person to Membership Chair or Treasurer, or by mail to: AAI, PO Box 111, Garwood, NJ 07027-0111 DOME DUTY January 23 Team C January 30 Team D February 6 Team E February 13 Team A February 20 Team B FRIDAYS AT SPERRY January 23, 2009 "Our Eye from Above: The Hubble Space Telescope" Michelle Tofel January 30, 2009 "Ask Dr. Lew" Dr. Lew Thomas February 6, 2009 "What's Up? A Down to Earth Sky Guide" Kathy Vaccari February 13, 2009 "The Galilean System" Mary Ducca All schedules above were accurate at time of publication. Please check www.asterism.org for latest information (click on "Club Activities") DR. LEW'S SEMINARS See Dr. Lew Thomas for possible upcoming seminar topics. (Choice of topic at Dr. Lew's seminars is determined by partici-pants' interest) February 2009 belongs to Venus. Although the "Evening Star" had its maximum elongation from the Sun last month, it still does not set until at least three hours after sunset. In fact, Venus can be seen in a clear blue sky during the daytime if you know exactly where to look and have some object to focus on. The crescent Moon provides such a guide on the 27th. Binoculars may be needed at first, but then try naked eye. The other events this month are mostly for the imagination of the armchair astronomer. Jupiter, Mars, and Mercury spend the last half of the month very close to each other, but the geometry could not be worse for the northern hemisphere. The frigid morning twilight would be bad enough, but the angle that their orbits make with the horizon is so small that they don't become visible until the Sun is almost up. The thin crescent Moon joins the trio on the 23rd, but the line formed by the Moon, Mars, Jupiter, and Mercury is almost horizontal and less than five degrees above the horizon by the time the Sun washes out everybody. The southern hemisphere has a different story entirely, of course. Not only is it a lovely summer morning down under, but the four objects are now in a vertical line more than ten degrees high with Mercury on top no less. The Moon actually passes over both Mercury and Jupiter within a two hour period. The stretch of Pacific coast between Alaska and Japan can witness both occultations. Uranus reaches aphelion, its maximum real distance from the Sun this month. Since this happens only once every 84 years, it is a true once- in-a-lifetime event, but it is not close to being the rarest event of the month. Ceres, the largest asteroid and first to be discovered, is at its closest opposition from the Sun since Valentine's Day 1857. It will not be this close to the Earth again until May 9, 4164! Like the three other lunar eclipses this year, the one this month is pathetically weak and totally invisible from New Jersey. Saturn gains a quarter of a magnitude in brightness during February as its rings tilt more and it approaches its opposition next month. It rises just after the end of evening twilight.