The SkyscraperVol. 36 No. 9 September 2009 Amateur Astronomical Society Of Rhode Island · 47 Peeptoad Road North Scituate, RI 02857 · www.theSkyscrapers.org Seagrave Memorial September Meeting Observatory is open with Brendan Hermalyn to the public weather permitting Friday, September 4 at Seagrave Memorial Observatory Skyscrapers’ September monthly is to confirm the presence or absence of meeting will feature a talk by Brendan water ice in a permanently shadowed Hermalyn on NASA’s upcoming Lunar region on the moon, and to constrain the CRater Observing and Sensing Satellite properties of the lunar regolith in that (LCROSS) Mission. region. On October 9th, 2009, LCROSS Brendan Hermalyn is a graduate will use the upper stage of the launch Saturdays 8:00pm - 10:00pm student at Brown University in vehicle as a kinetic impactor to form See www.theSkyscrapers.org for updates. Planetary Sciences, and is a science a crater and excavate of sub-surface team member on the LCROSS mission material. The impact and resulting with Dr. Peter Schultz. His graduate ejecta will be viewed and analyzed by Register Today for work is focused on understanding a suite of instruments on a shepherding the ejecta distribution resulting from spacecraft as well as a comprehensive AstroAssembly 2009 hypervelocity impacts. earth-based observational campaign. Friday, October 2 In 1999, the Lunar Prospector The ejecta curtain is expected to & Saturday, October 3 mission detected hydrogen signatures be viewable on earth by 10-12 inch Seagrave Memorial Observatory in permanently shadowed craters on telescopes or larger, providing a unique Speakers: Ronald Florence, Thomas the poles of the moon. These signatures opportunity for amateur observation. Levenson, Mike Mattei, William Sheehan may indicate the presence of water ice This talk will go over the details of Friday Night Informal Talks in some form on the surface of the the mission and expected observation Solar Observing • Swap Tables • On-Site moon. The goal of the LCROSS mission possibilities. Vendor • Raffle & Door Prizes Evening Reception • Buffet Dinner Observing at Seagrave Observatory President’s Message Bob Horton September 2009 On behalf of Skyscrapers, I would far this summer. Although past its 4 Full Moon like to thank Dick Parker, Craig Cortis peak, the Perseid Meteor Shower was and Bob Forgiel for providing us with still active, and we saw many bright 11 Last Quarter Moon their wonderful presentations at our meteors streaking across a beautiful, last monthly meeting. Many of our star filled sky with the brilliant Milky 17 Uranus at opposition members have been requesting more Way stretching overhead. practical amateur astronomy level talks, Both Jack Szelka and myself entered Saturn at superior and based on all the positive comments telescopes in the telescope making conjunction I have heard, it sure seems that competition. Although neither of us 18 New Moon everyone really enjoyed hearing about won any awards, we sure had a lot of their observing and astrophotography fun using our homemade scopes under 20 Venus 0.5° N of Regulus projects. those wonderful skies. Congrats to Al It was great to see so many of our Hall who picked up a special award for Mercury at inferior members attending Stellafane this a lens testing device he entered in the 20 conjunction year. The weather for all three days mechanical competition. 22 Autumnal Equinox was perfect, and we enjoyed some Check out the images of Stellafane in of the best observing conditions so the Gallery section of our web site. 26 First Quarter Moon THE SKYSCRAPER • SEPTEMBER 2009 As much fun as Stellafane can Getting ready for a big event like be, I always look forward to Astro Astro Assembly requires a lot of help Assembly each year, which is now from members like you. The Trustees rapidly approaching on October 2nd will be scheduling some work sessions and 3rd. Now over 50 years old, our this month to prepare the buildings and annual Astro Assembly offers a nice grounds, so please consider helping program of speakers, exhibits and out if you can. We’re also going to need observing, along with an opportunity volunteers to help out with various to get together with many old and new tasks during Astro Assembly. If you friends. Mr. 2nd V.P. Steve Hubbard are willing to help, please see Steve The Skyscraper is published monthly by Skyscrapers, Inc. Meetings are usually held has put together a wonderful lineup Hubbard or myself at the September on the first Friday of the month. Public of speakers for us this year - check out meeting. observing is usually held every Saturday the flyer in this issue of the Skyscraper Clear Skies, night at Seagrave Memorial Observatory, for more details. Bob Horton weather permitting. President Epsilon Pegasi: The Pendulum Star Bob Horton [email protected] Glenn Chaple 1st Vice President Bob Napier [email protected] This month, we’re going to pay a visit to motion of the primary a split second earlier, 2nd Vice President epsilon Pegasi (Enif), the “Pendulum Star.” It’s so the companion seems to lag behind. Rapid Steve Hubbard [email protected] an optical double star comprised of magnitude back and forth movement of the telescope 2.5 and 8.7 component stars separated by 144 generates the illusion of pendulum-like Secretary seconds of arc. Pairs this wide usually don’t motion. Jim Crawford [email protected] merit much consideration, but wait! Epsilon The Pendulum Star received plenty of Treasurer Pegasi has a surprise for us. recognition in astronomy guidebooks written Lloyd Merrill [email protected] After centering this pair in the eyepiece field in the late 19th and early 20th century – a (60-100x is the recommended magnification), time when double stars enjoyed tremendous Members at Large mentally trace a line between them. While popularity. Nowadays, with attention directed Tom Thibault [email protected] keeping your eye at the eyepiece, gently jiggle towards nebulae, clusters, and galaxies, epsilon Roger Forsythe [email protected] the telescope back and forth so that the two Pegasi receives scant notice. Trustees stars move at right angles to the imaginary The finder chart shows the location of Jim Brenek [email protected] line. While the golden yellow primary (a K- epsilon Pegasi. If you hunt down deep-sky Steve Siok [email protected] type star) travels serenely back and forth, the objects by the star-hop method, you may Tom Barbish [email protected] little companion seems to swing wildly to and recognize it as a pointer (with nearby theta fro, like a clock pendulum. It’s one of the most Pegasi) to the globular cluster M15. Next time Star Party Coordinator Bob Forgiel [email protected] amazing telescopic optical illusions you’ll ever you plan to visit M15, take a moment to check witness. out epsilon Pegasi. This star will put on a show Librarian What’s happening? According to Sir John that’s sure to dazzle! Bruce Merrill [email protected] Herschel, who was among the first to describe Your comments on this column are Historian the “Pendulum Star,” the oscillations are due welcome. E-mail me at gchaple@hotmail. Dave Huestis [email protected] to the longer time it takes light from the com. faint star to affect the retina. We detect the Editor Jim Hendrickson [email protected] Directions Directions to Seagrave Memorial Observa- tory are located on the back page of this newsletter. Submissions Submissions to The Skyscraper are al- ways welcome. Please submit items for the newsletter no later than September 20 to Jim Hendrickson, 1 Sunflower Circle, North Providence, RI 02911 or email to [email protected]. Email subscriptions To receive The Skyscraper by email, send email with your name and address to [email protected]. Note that you will no longer receive the newsletter by postal mail. 2 The Pleasures of Jupiter Dave Huestis As you may recall from an earlier four full moon diameters) to the lower Jupiter and casts a shadow onto the column, I reported that the United right of the Moon. Jovian cloud tops, it is called a transit. Nations General Assembly had This sky scene will be quite beautiful Besides seeing the satellite’s shadow, designated 2009 as the International to the naked-eye. But before you focus you may also see the bright disk of the Year of Astronomy. This year-long your telescope on Jupiter (and/or the satellite traversing Jupiter’s clouds at celebration was designed and initiated Moon); try observing the pair with the same time, though this event is to focus attention on astronomy — 400 binoculars. The Moon will be quite more difficult to observe. A moon may hundred years after Galileo first trained bright. If you have a pair of 10 X 50 also pass behind the planet, which is his telescope on the heavens. binoculars you can even spot one or called an occultation. Jupiter’s shadow And one of the first heavenly two of Jupiter’s moons. However, to can even eclipse a satellite as well; objects Galileo observed was Jupiter. appreciate all the beauty and dynamic gradually the moon will either blink On January 7, 1610, Galileo observed events this system has to offer requires out or reappear. Also, it’s fun to watch Jupiter through one of his improved a telescope. all four moons line up on one side of 30 power telescopes. He noticed three Even if you have a small inexpensive the planet. As you can see there’s much smaller bodies in Jupiter’s vicinity telescope, your optics are much better to observe in Jupiter’s vicinity. arranged in a straight line. After than those Galileo used to conduct his In addition, you’ll easily notice the watching Jupiter for several nights observations.