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Return-path: <ota+space.mail-errors@andrew.cmu.edu> X-Andrew-Authenticated-as: 7997;andrew.cmu.edu;Ted Anderson Received: from hogtown.andrew.cmu.edu via trymail for +dist+/afs/andrew.cmu.edu/usr11/tm2b/space/space.dl@andrew.cmu.edu (->+dist+/afs/andrew.cmu.edu/usr11/tm2b/space/space.dl) (->ota+space.digests) ID </afs/andrew.cmu.edu/usr1/ota/Mailbox/8bsQBVK00WBwM7xk5E>; Sat, 16 Mar 91 02:04:02 -0500 (EST) Message-ID: <IbsQBQu00WBw87w051@andrew.cmu.edu> Precedence: junk Reply-To: space+@Andrew.CMU.EDU From: space-request+@Andrew.CMU.EDU To: space+@Andrew.CMU.EDU Date: Sat, 16 Mar 91 02:03:57 -0500 (EST) Subject: SPACE Digest V13 #277 SPACE Digest Volume 13 : Issue 277 Today's Topics: Electronic Journal of the ASA - March 1991 Administrivia: Submissions to the SPACE Digest/sci.space should be mailed to space+@andrew.cmu.edu. Other mail, esp. [un]subscription requests, should be sent to space-request+@andrew.cmu.edu, or, if urgent, to tm2b+@andrew.cmu.edu ---------------------------------------------------------------------- Date: 14 Mar 91 16:20:06 GMT From: shlump.nac.dec.com!advax.enet.dec.com!klaes@decuac.dec.com (Larry Klaes) Subject: Electronic Journal of the ASA - March 1991 THE ELECTRONIC JOURNAL OF THE ASTRONOMICAL SOCIETY OF THE ATLANTIC Volume 2, Number 8 - March 1991 ########################### TABLE OF CONTENTS ########################### * ASA Membership/Article Submission Information * 1990 Georgia Star Party Retrospective - Compiled from comments of GSP participants * Aperture Arrogance - Eric Greene ########################### ASA MEMBERSHIP INFORMATION The Electronic Journal of the Astronomical Society of the Atlantic (EJASA) is published monthly by the Astronomical Society of the Atlantic, Inc. The ASA is a non-profit organization dedicated to the advancement of amateur and professional astronomy and space exploration, and to the social and educational needs of its members. Membership application is open to all with an interest in astronomy and space exploration. Members receive the ASA Journal (hardcopy sent through U.S. Mail), the Astronomical League's REFLECTOR magazine, and may additionally purchase discount subscriptions to ASTRONOMY, DEEP SKY, SKY & TELESCOPE, and TELESCOPE MAKING magazines. For information on membership, contact the Society at: Astronomical Society of the Atlantic (ASA) c/o Center for High Angular Resolution Astronomy (CHARA) Georgia State University (GSU) Atlanta, Georgia 30303 U.S.A. asa%chara@gatech.edu or asa@chara.uucp ASA BBS: (404) 985-0408, 300/1200 Baud. or telephone the Society recording at (404) 264-0451 to leave your address and/or receive the latest Society news. ASA Officers and Council - President - Don Barry Vice President - Nils Turner Secretary - Ken Poshedly Treasurer - Alan Fleming Board of Advisors - Edward Albin, Bill Bagnuolo, Jim Bitsko Council - Jim Bitsko, Bill Crane, Toni Douglas, Eric Greene, Larry Klaes, Tano Scigliano, Bob Vickers, Michael Wiggs, Rob Williams ARTICLE SUBMISSIONS - Article submissions to the EJASA on astronomy and space exploration are most welcome. Please send your on-line articles in ASCII format to Larry Klaes, EJASA Editor, at the following net addresses or the above Society addresses: klaes@advax.enet.dec.com or - ...!decwrl!advax.enet.dec.com!klaes or - klaes%advax.dec@decwrl.enet.dec.com or - klaes%advax.enet.dec.com@uunet.uu.net You may also use the above net addresses for EJASA backissue requests, letters to the editor, and ASA membership information. Please be certain to include either a network or regular mail address where you can be reached, a telephone number, and a brief biographical sketch. DISCLAIMER - Submissions are welcome for consideration. Articles submitted, unless otherwise stated, become the property of the Astronomical Society of the Atlantic, Inc. Though the articles will not be used for profit, they are subject to editing, abridgment, and other changes. Copying or reprinting of the EJASA, in part or in whole, is encouraged, provided clear attribution is made to the Astronomical Society of the Atlantic, the Electronic Journal, and the author(s). This Journal is Copyright (c) 1991 by the Astronomical Society of the Atlantic, Inc. 1990 GEORGIA STAR PARTY RETROSPECTIVE Compiled from comments of GSP participants Astronomy, telescopes, and fun! Nineteen Ninety's Georgia Star Party (GSP) had all three and the weather even became friendly after early threats. By closing time, over 93 people had been involved in making this one of the ASA's most successful and appealing endeavors. The 1990 GSP was held at the Hard Labor Creek Observatory (HLCO) in East Georgia from Thursday, October 11 to Sunday, October 14. Eric Greene remarked, "The weather was, well, exciting! The meeting of dying tropical storms Klaus and Marco with a strong cold front pushing in from the northwest - along with hurricane Lily sitting a few hundred miles to our east - provided some speculation of this becoming the second annual Georgia 'Rain' Party." And rain it did, at least on Thursday night, with occasional rain through early Friday. However, a break in the clouds presaged a complete clearing of the skies as dinner was served Friday evening, although clouds returned shortly after observing commenced. There were enough telescopes and discussion groups to keep would-be observers occupied, though, and everyone was still awake when a rapid clearing brought cooler temperatures and perfectly transparent skies at midnight. The weather was beautiful for the rest of the night and crowds remained active at the camp field and the observatory until nearly dawn! Saturday brought a few clouds, but skies were mostly clear as afternoon talks competed with views through several hydrogen-alpha filters of some impressive prominences and plage regions on the spotted Sun. A Lumicon H-alpha filter mounted on a moderate-sized refractor showed prominences easily at low magnification around the entire solar disk. The "star" filter, a $2,500 Daystar filter from the observatory, brought gasps from members who saw fine detail in solar prominences and faint tendrils of magnetic activity in the solar chromosphere. Instrumentation varied from the unaided eye to Tectron's 75-centimeter (thirty-inch) Dobsonian telescope and Vic Menard's 17.5-centimeter (seven-inch) Starfire refractor, the stars of the armada of visiting telescopes. Homebuilts and commercial instruments shared the camp field and observatory yard and the availability of large instruments at both sites kept lines down to just a few people at these big telescopes - a definite advantage. Both sites were well populated with the more conventional instruments as well, and an interesting population it was. A few small refractors matched their apertures against huge Dobsonians. Equatorially mounted telescopes as large as the CHARA forty-centimeter (sixteen-inch), Beck 75-centi- meter, and a Meade DS-16 made for good astrophotography and long looks at deep-sky objects and planets. The facilities for the campers were excellent. While the cabins were a bit rustic, the central dining hall and kitchen provided excellent facilities. The hot showers and covered pavilions made camping an almost luxurious experience compared to more primitive facilities at other similar gatherings. We discovered, almost too late, that the camp also provided complimentary boating gear and two flat-bottomed boats to explore the scenic Lake Rutledge that enclosed the camp on two sides. The large kitchen area with modern ovens and stoves made preparation of evening meals for 60+ people a relatively simple process. Despite the dining hall's ample size, the fine weather and scenic surroundings of the outdoor pavilion led us to dine outdoors both nights, watching blue sky give way to stars as we finished our meals and listened to evening entertainment. The dining hall served instead as our meeting head- quarters, where the afternoon programs arranged by program chairman Bill Hartkopf covered a wide variety of topics. The final schedule of talks were varied and informative. To lead off the Friday schedule, Don Barry discussed the instrument revolution in amateur astronomy, with emphasis on the migration of CCDs and computerized motion control from professional instruments to amateur telescopes. He described the late bloom of photographic technology, including hypering and cold-camera techniques, and then presented exposures taken with a Meade twenty-centimeter (eight-inch) telescope with an affordable SBIG-ST4 CCD camera. The audience was star for Part Two, in which innovations devised by Amateur Telescope Makers were shown and discussed. Francis Cordele of the Barnard Astronomical Society displayed his innovative foldable binocular holder stand, and the ASA's own Jeremy and Corey Schiffer explained the unique focusing mechanism of their 25-centimeter (ten- inch) Dobsonian, fabricated with a microfiche reader's motor. Joe Haley of the Tallahassee Astronomical Association of Florida exhibited his modification of the Dobsonian mount to take pressure off the teflon supports to enable butter-smooth motion of both axes. Jim Brant also demonstrated the new digital setting circle technology for his Celestron 8. As the formal program ended, the crowd broke into small discussion groups over each instrument as food was readied outdoors. Soon the smell of hamburgers brought everyone out to a hearty picnic-style meal as the sky cleared. The second afternoon brought a more varied slate of programs. Nils Turner led off with a discussion of infrared astronomy, spanning both techniques to detect infrared radiation, to the types of objects that were best studied in the infrared and the information that could be gathered from infrared observations. His own research has measured the shape and structure of a bright infrared star/dust complex which is practically invisible at visible wavelengths. Bill Bagnuolo next gave a talk on his MTT (Multi-Telescope Telescope) project, which involves participation by a number of ASA astronomers and volunteers. This instrument will be the largest effective telescope in the Southeastern United States upon completion. It will measure radial velocities and chemical compositions of hundreds of stars in the binary star research effort of the Center for High Angular Resolution Astronomy (CHARA). See the EJASA article, "The CHARA Multi-Telescope Telescope", by Hal McAlister in the August 1989 issue for more details on the MMT. Next came the traditional light entertainment of past Star Parties: The GSP Quiz Bowl! Ten players volunteered (some under duress!) to pit their skills as two teams against each other - the resident astronomers and the audience. Toss-up questions from Don Barry, Bill Hartkopf, and Bill Bagnuolo were answered by individuals on either team, entitling their team to, as a whole, answer more detailed questions formulated by the audience. Toward the end, questions escalated in value and the competition got fierce, even as the latitude for answers was increased. Some examples: "Toss up! The most abundant element in the Universe..." "BUZZ!" "Yes, Roger?" "Hydrogen!" "That is incorrect. Team A: The most abundant element in the Universe *after* hydrogen and helium is what?" Not to appear unfavorable to Team B, which led by a considerable margin, we also permitted the following exchange: "Bonus question, Team B. Name the two mathematicians and one observer associated with the discovery of Neptune." "(Pause) Well, there was Adams, and then (Pause) Lavoisier. Gee, golly." "That's it! Adams, Leverrier, and *Galle*! Half a point for 'Lavoisier'." (Johann Galle of Berlin, Germany was the third of the troika.) If the talks and quiz bowl were not enough, there were still other entertainments. Bob Summerfield brought from Pennsylvania a fascinating collection of astronomical t-shirts and paraphernalia. An active swap- table emerged, with items ranging from a fifty-dollar 12.5-centimeter (five-inch) Aero-Ektar lens to batteries and motors for small telescopes. In the Recreation Cabin, an inflatable Starlab dome was erected to house a capable Spitz 1-A planetarium projector dating from 1951. Each evening at the observatory, demonstrations of the ST4 CCD camera were conducted, yielding impressive shots of the Crab Nebula and even revealing the Horsehead Nebula in one fortunate exposure. The darkroom was used to demonstrate before a crowd of twenty or so the process of developing film. Society members trained most of the attendees in the proper use of the CHARA forty-centimeter telescope from Kitt Peak. The Beck 75-centimeter telescope also took its turn looking at the list of famous and not-so-famous celestial objects. Bill Hartkopf, Deborah Cline, and Nils Turner camped at the observatory, keeping equipment stored there secure between the observing evenings. They also donated a good bit of time in the not-too-difficult cleanup operation, in which they were joined by the Poshedlys, Toni Douglas, Julian Crusselle, Jeremy and Corey Schiffer, Jim Bitsko, and a host of other volunteers. The Poshedlys, Bill Hartkopf, Deborah Cline, Toni Douglas, and Julian Crusselle also brought much of the yogurt, coffee, fruit, doughnuts, and other snacks that enlivened the mornings as everyone groggily restored themselves after a long night's observing. Everyone stayed well fed, well entertained, and completely saturated with astronomical fun. Saturday morning, a meeting of the minds took place of representatives from societies across the Southeast. With this meeting, the SouthEast Regional Astronomical League (SERAL) was effectively reborn, and given a new constitution, representatives, and purpose. Our own ASA BBS will serve as official "computer communications" vehicle for SERAL, and the Society's Georgia Star Party, for at least the next one or two years, will be the regular official regional convention. What SERAL will become remains something of a vacuum to be filled by the new SERAL officers, but it was good to see an excellent showing of societies from across the region present. There was active interest by all of them regarding ways to better unify and complement our activities, in order to better serve regional amateur astronomers. The conclusion of those present was that amateur astronomy is alive and well. The number of innovations present in the equipment showed that it is not at all a stagnant hobby. The computer revolu- tion has brought enormous capability to amateur instruments. The amateur interest for contributing where possible to professional astronomy was also alive and well. As a way of example: From the front yard of the observatory, Roger Venable measured a planetoid appulse to a bright star which has been reported to the International Occultation Timing Association (IOTA), where it will refine knowledge of that planetoid's orbit. About the Authors - This article borrowed heavily from Eric Greene's and others' summaries of GSP events in active discussion on the Society Computer Bulletin Board following the event. APERTURE ARROGANCE by Eric Greene I have come to notice a trend, perhaps more of a feeling, that many astronomers today tend to believe that astronomy cannot be done with 'small' telescopes anymore. "Aperture fever" has become preva- lent across the field - fueled, in part, by widely available, inex- pensive Dobsonian reflectors. A developing counter theme to this ideology is that astronomy cannot be done without recourse to the finest optics money can buy. Civilized battles rage over the advantages of using large aperture fluorite apochromatic refractors over massive Dobsonians, where fifty centimeters (twenty inches) of aperture denote a medium-sized instru- ment. The common denominator here is expense, in many cases far be- yond what can be considered economically feasible for most hobbyists. I have seen people leave messages on astronomy computer bulletin boards or have them call me about attending ASA observing sessions and speak apologetically about "only having a 60mm Tasco" or "just a small telescope from Sears." They are 'victims' of what we might call "aperture arrogance". Certainly there is nothing to sneer about when looking at a magnificent Astro-Physics Starfire 17.5-centimeter (seven-inch) refractor on a beautifully machined Byers mount or one of the new generation of huge Dobsonians seen in every issue of SKY & TELESCOPE magazine. Copywriters add to the feelings of inferiority with their glowing prose describing the wonderful details of faint celestial objects to be seen through one of these telescopes. Such telescopes reside in our dreams of "one of these days!", while we continue to make mortgage payments and try to keep food on the table. We pull out that small telescope, shake our heads sadly, and forego the ob- serving pleasures that do await its modest dimensions. Even after saving up the pennies for several years in order to buy that dream telescope, we are then subject to a similar situation when we hear people talk condescendingly about the "inferiority of mass- produced optics" and the "optical degradation of oversized secondary mirrors." We feel it necessary to apologize to ourselves, if no one else, about having only a catadioptric and how we are planning on upgrading "one of these days." What absolute and unmitigated hogwash! It has always been my feeling that the best telescope in the world is the one you have at any particular time. You cannot see a thing through the photographs of telescopes found in magazine advertisements, but you certainly can open up the wonders of the heavens with that "only a Tasco" sitting in the closet. One of the most interesting rules of observational astronomy has always been "it takes much less aperture to see an object than it takes to discover it." The foundation of the rule is that an eye which knows what it is looking for can see something with much less aperture than an eye that does not. Training the eye to see what is there in space costs nothing but time. A well-trained eye can make up for a lack in telescope size. I see this demonstrated at every ASA Star Party we host. Some observers can spot those faint objects that others, even with bigger telescopes, cannot pick out at all. Sure, that 60mm refractor is not going to find Stephan's Quintet, but there are thousands of other, brighter objects found in the sky. The training you give yourself with a small telescope will never be lost and will help you greatly as you move up to bigger instruments. Do not apologize for that small telescope. Instead, revel in its ease of use and portability! Sure, it may give dim views of many night sky objects, but the point is that you *can* actually see these celestial wonders. Much of the problem with these devices is the fact that the eyepieces provided with the telescope are woefully inadequate. High quality oculars for Japanese telescopes are widely available and very modest in price. Rather than spending thousands of dollars for a bigger telescope, a few hundred dollars invested in a couple of new eyepieces might open up observing vistas thought impossible with the small, high-power optics usually supplied with these instruments. The most important thing, though, is to get out there and use the telescope. Learn its strong and weak points and do not be afraid to take some tools to your instrument in order to improve its performance. Found a wobbly tripod? Keep the legs completely collapsed and observe from a chair rather than extending the legs to allow stand-up observing. Give some thought about what can be done to make the mount more stable and use low-power eyepieces. Cannot track objects because of the alt- azimuth mount? Consider building a simple equatorial mount out of pipe or wood. It is not a difficult task and will make using the telescope at higher power much easier. Cannot find celestial objects in the first place? Throw away that finder, put a Telrad on the telescope, and spend a few dollars for some good star charts. Then take time to learn the night sky. One good way is to join some local astronomy observing sessions and let others show you how to effectively use the aperture you have, rather than just wishing for a bigger telescope. There is an entire Universe awaiting your time and efforts. No matter what your optical instrumentation - naked eye, binoculars, or small telescope - there are more interesting objects to view in the sky than most people will be able to witness in their lifetimes. Related EJASA articles - "Amateur Telescopes, Yesterday and Today", by Bill Bagnuolo, September 1989 "Low-Budget Astronomy", by Tony Murray, October 1990 About the Author - Eric Greene, ASA Observing Coordinator, is an active and avid amateur with a talent for astronomical education and an interest in presenting astronomy comprehensively to all levels of interest in the field. Eric is the recipient of the ASA's 1990 Meritorious Service Award for his work as the Society's observing coordinator and for founding and maintaining the ASA electronic bulletin board service (BBS). Eric is the author of "The Cosmic Distance Scale" in the April 1990 issue of the EJASA. THE ELECTRONIC JOURNAL OF THE ASTRONOMICAL SOCIETY OF THE ATLANTIC March 1991 - Vol. 2, No. 8 Copyright (c) 1991 - ASA ------------------------------ End of SPACE Digest V13 #277 *******************