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News from the Society for Astronomical Sciences News from the Society for Astronomical Sciences Vol. 9 No. 4 (October, 2011) SAS at PATS-2011 The Society for Astronomical Sciences had a productive presence at this year’s Pacific Astronomy and Tele- scope Show. Our booth display, designed to en- courage curiosity and interest in small- telescope science, seemed to gener- ate a nice response. Quite a few visi- tors engaged us in long conversations about projects, equipment, and the research contributions that are made by backyard scientists. We didn’t keep count, but at least a hundred people picked up SAS brochures. Also at PATS, Brian Warner presented a lecture on “Measuring the Universe”, which focused specifically on finding variable stars, and determining their lightcurves. About 40 people attended the lecture, and at least half of them accepted free copies of MPO Canopus, to facilitate their own entry into “backyard science”. If you are giving a lecture or participat- ing in a conference, and would like some SAS brochures to hand out, or the 3-poster SAS display, contact Bob Buchheim. Gene Lucas (left) explains the value of small-telescope science to a visitor at the SAS booth during PATS-2011. Photo by Bob Buchheim. Call for Observations of Zeta Aurigae Eclipse making these eclipses 10 times less during, and after the Octo- rare than the 9890 day cycle for Epsi- ber/November 2011 primary eclipse Here is a project that will build on your are needed – most particularly during experience with Epsilon Aurigae, and lon Aur. Primary eclipses occur when the B-star is eclipsed by the (much the ingress and egress stages, where enable you to contribute to the study of the hot star acts as a probe for the a stellar atmosphere. larger) K-star. The depth of the pri- mary eclipse is strongly dependent on extended atmosphere of the super Zeta Aurigae (= TYC 2899-2236) is a the band that you observe in. The V- giant. Observations are probably go- 3.7-mag star, located a bit less than 3 band depth is about 0.15 mag, and the ing to be attempted with CHARA dur- degrees from Epsilon Aurigae. It is a eclipse is much deeper in B and U ing these phases. binary system: the primary component than it is in V or R. The secondary Photometric coverage of the ingress is a K giant star, and the secondary eclipse (when the blue star transits in and egress phases, especially in U star is a very hot, blue, and much front of the red star) is shallower – less and B bands, will be helpful to define smaller B5 star. The two form an than 0.1 mag – and apparently is the time of eclipse and search for re- eclipsing binary pair with a (reportedly) poorly characterized. lated shorter-term variations. Investi- eccentric orbit. The orbital period is gators are especially interested in Blue 972 days (approximately 2.66 yr), Observations of this system before, Society for Astronomical Sciences Newsletter Vol 9 Number 4 and Ultraviolet photometry to precisely based on his observations of the 1985 “New Look” of the Journal define the ingress and egress phase eclipse: timing. Precise V band photometry will Ingress duration ~ 4 days for Occultation Astronomy also be helpful in this regard. Totality duration ~ 36 days One of the most active and important Egress duration ~ 4 days research areas for small (and very Spectroscopic observers will see the Eclipse duration ~ 44 days biggest changes at the shortest wave- small) telescopes is the timing and lengths. Jeff has prepared a Zeta Aur cam- recording of stellar occultations by paign website, at: solar system objects (mostly aster- Spectra will almost certainly be inter- oids). The International Occultation esting, but will probably need to extend http://www.hposoft.com/EAur09/zeta% Timing Association (IOTA) is the coor- deep into the blue/violet to show 20Aurigae/zeta.html dinating body for these activities. eclipse effects (which of course will be difficult with standard CCDs). This Refer to Jeff’s website for the most The IOTA’s publication (formerly “Oc- makes it a challenging set of observa- current information and updates. cultation Newsletter”) has been dra- matically upgraded in the past year, tions, but the SAS membership has A 1996 Astrophysical Journal Paper on taking on a new title (“Journal for Oc- demonstrated that they enjoy a chal- this system by Philip Bennett, et al can cultation Astronomy”), a new produc- lenge. be found at: tion arrangement (the IOTA European You may ask, “Why should small- http://www.hposoft.com/EAur09/zeta% Section is now accepting contributions telescope scientists observe and moni- 20Aurigae/Doc/1996BE.PDF and handling the preparation of the tor this system?” Dr. Robert Stencel Journal) and an energetic Editor-in- offered several reasons to put this Dr. Bennett offers the following advice: Chief (Hans-J. Bode). Mr. Bode and system high on your observing sched- “I am very pleased to see the attention his many helpers and contributors are ule: you and your fellow observers are de- to be congratulated on bringing this voting to this interesting and useful new vision to fruition. The past few • It will be undergoing its primary binary system. issues have included excellent “how eclipse. This is an opportunity to get to” explanations of equipment and data dense photometric and spectroscopic “I am particularly interested in spectra. reduction methods, and reports of oc- coverage under favorable observing The best region is in the blue-violet- cultation observations. conditions. near UV (3200-4250 Å). Shorter wavelengths are more useful, but also Mr. Bode notes in an editorial that • As with many bright stars, large ob- more difficult to observe. It is probably there is an important opportunity for servatories cannot easily get time to impossible for most amateurs to ob- collaboration between occultation tim- conduct these observations. Thus, it is serve below 3500 Å because regular ing and asteroid lightcurve photometry: likely that investigation of this object optical glass absorbs strongly at wave- the photometry provides information must depend on backyard scientists lengths shorter than this (special optics about aspect ratio and shape of the and their modest telescopes. made of fused silica optics are object (but is agnostic regarding the • Spectra spanning the time before, needed). object’s actual size) while the occulta- through, and after the eclipse will be “The key times to observe are nightly tion timing can provide calibration of most interesting. for the 2 weeks prior to the start of the physical size of the asteroid. He eclipse, during total eclipse, and for strongly encourages asteroid pho- • This is an exploratory project. Even if tometrists (i.e. many SAS members) to observations are ambiguous this time the 2 weeks following emergence from eclipse. Spectroscopic signatures of specifically attempt lightcurves of oc- around, the results will prove valuable cultation targets, either shortly before to plan for future observing campaigns. the supergiant's atmosphere remain visible for ±2 weeks from total eclipse. or after the occultation. There have Happily, this eclipse comes at a good been a few recent research articles time. It is well placed for Northern “If any of you are able to observe in published that combine lightcurve, hemisphere observing, in a good posi- the blue-violet-near UV on a regular shape-modeling, and occultation re- tion for late night or early morning ob- basis, I would be *very* interested in sults, and they have been pretty re- serving. For those observers that hearing from you directly.” markable in terms of consistency, have been monitoring epsilon Aurigae, here is a very near neighbor that needs your attention! The current prediction for first contact is 29 October 2011, with mid-eclipse on 19 November 2011. You should plan on concentrated observing (nightly time-series photometry of spectroscopy) beginning in mid- October (i.e. “right now”), and continue through at least 17 December 2011. Jeff Hopkins provided the following estimates of the eclipse phenomena, A melancholy astronomer observes a foggy dusk at Cerro Tololo. Photo by Bob Stephens. 2 Society for Astronomical Sciences Newsletter Vol 9 Number 4 quality, and teamwork. successful observation of Pluto’s May and named asteroids, with the moniker 22, 2011 occultation of a 14th magni- (221149) Cindyfoote. It is named in On a vaguely related subject, some- tude star. Not surprisingly considering honor of SAS’ own Cindy N. Foote. time in the past couple of years I heard the star’s faintness, the data is noisy, a talk that included the quip that “If we but the occultation is definitely visible She obtained her first telescope on a keep treating Pluto like an asteroid, in their lightcurve. Congratulations, dare with her husband, Jerry. Within 4 pretty soon it will start acting like one!” John and Meg! years, she became one of the leading (Alas, I can’t remember who to credit amateur astronomers in the field of that quip to). In keeping with this pre- exoplanet observing. She has been diction, Pluto has been the subject of co-author on at least four papers on occultation observations just like other (221149) Cindyfoote exoplanets in professional journals. asteroids. In the July-Sept 2011 issue Asteroid 2005 TG61 was discovered of the Journal for Occultation Astron- Congratulations to our newest "rock on 2005 Oct. 3 by the Catalina Sky omy, longtime SAS member John star"! Survey. The IAU has now approved Menke and his wife Meg report their its entry into the catalog of numbered Small-Telescope Astronomical Science in The major result reported here is use of this data to anchor models of the upwelling and the zonal winds at depth in Sat- the News urn’s atmosphere.
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