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Society Amateur Astronomy News and Views in Southwestern Virginia Roanoke Valley Astronomical Society Amateur Astronomy News and Views In Southwestern Virginia Volume 31—Number 2 February 2014 RVAS January Meeting Notes Coming to you live . by Rick Rader, RVAS Secretary From Seattle, Washington, it's--wait, wait, don't tell me! Sorry to steal a line from the Sunday morning NPR pro- gram, but our January Club gathering was yet another example of why you may wish to brave the elements to meet with your fellow all-things-astronomical enthusi- asts. In a first for a monthly meeting, RVAS President Frank Baratta and Mark Hodges (all things mystical and elec- trical Science Museum master) orchestrated an intri- guing hour with Tom Field, live via webcast from his lo- cation in Seattle. A contributing editor at Sky & Tele- scope magazine and author of RSpec software, Tom re- Frank Baratta Tom Field galed the twenty eight hardy souls present with an ad- RVAS President connects with for the evening’s live webcast talk. venture delving into the surprisingly easy world of hard Photo by John Goss science: spectroscopic investigation of light emitting objects of all types in our universe. had been born. The bombardment of energy reaching Earth can be ana- Fast forward. Spectroscopy has taught us that every lyzed to reveal the constituent elements of a celestial element of the Periodic Table when heated emits or ab- object. The process is not brand new, having been first sorbs light of specific wavelengths, which appear as defined by Newton with his prism experiments. Joseph lines in their otherwise continuous, multi-colored spec- von Fraunhofer, a wonderfully skilled glass maker, ob- tra. Among other things, spectroscopy can even detect served 574 dark lines in the seemingly continuous spec- the motion (including rotation) of objects due to a Dop- trum of Sun in the early 1800s. He then equipped his pler shift in such lines: toward the blue end of the spec- telescope with a prism to study Venus, the Moon, Mars trum when the source is approaching and toward the red and Betelgeuse. The field of astronomical spectroscopy (Meeting Continued on page 4) RVAS NL— February 2014— Pg 1 of 12 President’s Message Astronomy and Humility I was sitting at the dining room table this morning, en- few asteroids. Now, surveys of hundreds of thousands joying the bright early morning sunshine again, as I of them are telling us that they formed throughout the have a fondness of doing, and listening to NPR. A spot solar system. How they collected mainly in the asteroid on some new astronomical findings came on and it belt involves new theories about planetary orbital dy- sparked a rush of thoughts. Somehow, it also reminded namics and the influence of Jupiter during the early me of a quote from Mark Twain, one with which I’m stages of the solar system. sure many of you are familiar. Interesting. But what impressed itself upon me was, When I was a boy of 14, my father was once again, science as an enterprise in which the proba- so ignorant I could hardly stand to have bility of change is “1”; that is, a certainty. In one way, the old man around. But when I got to this is truly annoying. It might be nice to have things be 21, I was astonished at how much the settled once and for all. But that way lies stagnation old man had learned in seven years. and decline. It’s likely that from the dawn of humanity older gener- ations have endured with a kindly (mostly) indulgence such attitudes that accompany our early years. It’s part of the process of individuation and maturation that we all pass through. We grow out of it, though some vestige of the attitude persists throughout our years, more so in some than in others. In the present case, the NPR spot that sparked these and other thoughts had to do with how the asteroid belt formed. Since the 1980s, astronomers had been Artist concept of an asteroid belt around a sun-like star. of the opinion that the asteroid belt formed in situ Image credit: NASA/JPL-Caltech from the same cloud from which the planets formed. Turns out that this opinion was based on observing too (Message Continued on page 3) The Roanoke Valley Astronomical Society is a membership organization of amateur astronomers dedicated to the pursuit of observational and photographic astronomical activities. Meetings are held at 7:30 p.m. on the third Monday of each month. See calendar on last page of news- letter for location. Meetings are open to the public. Observing sessions are held one or two weekends a month at a dark-sky site. Yearly dues are: Individual, $20.00; Senior Individual, $18.00; Family, $25.00; Senior Family, $22.00; Student, $10.00. Articles, quotes, etc. published in the newsletter do not necessarily reflect the views of the RVAS or its editor. Officers/Executive Committee/Editor/Webmaster Frank Baratta, President ([email protected] ) Sharon Stinnette, Vice President ([email protected]) Rick Rader, Secretary ([email protected]) Jeff Suhr, Treasurer ([email protected]) Carol Mesimer, Member at Large ([email protected]) Michael Good, Immediate Past President ([email protected]) Paul Caffrey, Past President ([email protected]) David E. Thomas, RVAS Newsletter Editor ([email protected]) Roger Pommerenke & David E. Thomas, Webmaster ([email protected]) RVAS web page: http://rvasclub.org RVAS NL— February 2014— Pg 2 of 12 (Message Continued from page 2) Indeed, imbedded therein lies a concept expressed by In fact, science is an ongoing lesson in humility. Oh, the late eminent philosopher of science Karl Popper, who sure, scientists (from professionals down to rank ama- asserted that a statement is "scientific" only if it is, teurs) are human and loathe to yield their cherished among other things, “falsifiable.” Or take the corollary theories and beliefs. But there’s a saying about Fate Einstein is reported to have said, “No amount of experi- that applies to the inevitability of change in the scienc- mentation can ever prove me right, but a single experi- es: You can go along with it peacefully or get dragged! ment can prove me wrong.” In Popper’s view, to say that a statement is “unfalsifiable” is not to say it is irrele- It may take a while—as in how long the geocentric view vant or without value, it’s just “non-scientific.” of the universe persisted—but eventually the weight of accumulating evidence demands acknowledgement. Science exacts a price from the practitioner: a hum- Sometimes it does so gently, other times like the force bling assent—whether consciously or not—that tomor- of two long-jammed tectonic plates releasing their pent row’s science may prove me wrong. It may be a litmus -up energies. In this, science differs from some areas test for our times. Those who would withhold their as- of human understanding. Science is a chain of unfolding sent are not practicing science. awareness in which each contribution is at least to some degree provisional. Frank Baratta Sears Applied Technologies Center Guilford Technical Community College Jamestown, NC 2014 March 1 For complete information: www.gtcc.edu/observatory/tristar RVAS NL— February 2014— Pg 3 of 12 (Meeting Continued from page 1) when the source is receding. What has been difficult to quantify without some major financial investments is now within reach for many ama- teurs with a variety of webcams, DSLRs (I would pro- pose mirror-less cameras will suffice, if good quality), astro CCD cameras, grating lenses and Mr. Field's RSpec software. One huge asset to this exercise is the imme- diacy of feedback. Once you have your image, you can download it to a laptop which will show the object and Tom demonstrates boxing a star’s spectrum (left side) and the spectrum on the left side of your screen. Engage the resulting analysis (right side) using RSpec software. the software and you will then see all the defined ab- Photo by Rick Rader sorption and emission lines in the continuous format with the specific wavelengths measured. You can then ing James and Darlene Thompson and Hart Gillespie determine the chemical, motion and other properties of from the Blue Ridge Astronomy Club in Lynchburg, your target. where Jim serves as President, and Erica Reed, who tutors at Roanoke’s Jackson Middle School. The Lynch- Tom is a very engaging, entertaining speaker and there burg group had accompanied RVAS members from Bed- was significant back and forth conversation as we were ford Jack Gross and Roger Yeager to the meeting. We all quite captivated by what we were seeing and hearing. hope you all felt welcomed and would love to have you You can see Tom in a ten minute Sky & Telescope inter- back. view from 2011 Northeast Astronomy Forum (NEAF) on YouTube at http://www.youtube.com/watch? v=ORK_Xwpt2B8. His website is RSpec-astro.com and is quite detailed in the equipment and software needed to apply yourself to this discipline. Tom also had an ar- ticle on the subject in the August 2011 issue of Sky & Telescope magazine. After thanking Tom and bidding him farewell, Frank called on Genevieve Goss for a short segment to close out the evening. Genevieve is just a wonderful speaker. Her topic was the Globe at Night and Night Sky Net- work—again, citizen science. The former’s activities focus on gathering star counts for specified reference areas by observers from their own homes all over the world to help measure light pollution. The current ref- erence area is Orion.
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