December 2007 - Utah-Astronomy - mailman.xmission.com

Moving Host
by Cynthia Blue 30 Dec '07

30 Dec '07

I am going to move utahastronomy.com to a new host. I have outgrown bluehost... which is a shared server. If ya'll have gotten any Exceed CPU error messages and can't display the site for a while, it's because I have a lot on it now. My bluehost account expires Feb 8 2008 and, before that happens, I'm moving. I'm leaving behind a Shared Host and going VPS. Virtual Private Server. Hopefully it'll solve the problems as I'll get more bandwidth. I have initiated the domain registrar transfer, it usually takes a few days to complete, and I should, in that time, be able to move the gallery and wiki over. Cross your fingers there will be minimal down time. :) I'm not getting mail list messages so if you have questions/comments/problems etc, please email me directly. :) Thanks for the patience... And thanks everyone who has contributed to server costs. The VPS will be a bit more, but not too much. Cynthia -- http://www.collierescueut.org/ Elsinore Lucilla Aurelius ASCA-CD RA CGC CH Pembroke Faded Glory VC AXP AJP RE HT CGC Angel Pumpkin Spice Lady DPP CGC Spirit Chasers Spice NA NAJ WVN CGC http://www.tiptail.com

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Current online pubs - BAA Lunar Section Journal
by Kurt Fisher 30 Dec '07

30 Dec '07

The December 2007 issue of the BAA Lunar Section's aperiodic lunar journal, The New Moon (vol. 16, no. 2), is available online at: http://www.baalunarsection.org.uk/tnm.htm It includes a beginner how-to article by lunar and DSO uber-imager Anthony Ayiomamitis. - Kurt _______________________________________________ Sent via CSolutions - http://www.csolutions.net

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Re: [Utah-astronomy] More on next month's possible impact
by Kurt Fisher 30 Dec '07

30 Dec '07

NPR's Ira Flatow interviewed NASA NEO program head Donald Yeomans about 2007 WD5 - now estimated at 50 meters in dia. http://www.sciencefriday.com/program/archives/200712281 Yeomans also joked that when further data is collected next week after the full Moon's glare isn't washing the sky out should reduce the probability of impact to zero. - Kurt _______________________________________________ Sent via CSolutions - http://www.csolutions.net

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Current online pubs - SAS Newsletter 5(3)
by Kurt Fisher 30 Dec '07

30 Dec '07

The current newsletter (undated, vol. 5, no. 3) of the Society for Astronomical Sciences is available online at: http://www.socastrosci.org/ - under the hyperlink "The latest newsletter may be accessed by clicking here!" Jerry Foote, a SLAS member, is on the SAS 2008 Symposium Committee. Important dates for submitting amateur papers to the SAS are: March 14: Abstracts for Symposium are due March 17: Acceptance notice April 20: Papers due for Proceedings The 2007 Symposium papers and individual posterboards are also available at their website. - Kurt _______________________________________________ Sent via CSolutions - http://www.csolutions.net

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Re: Meaning of emersion wrt to Io
by Kurt Fisher 30 Dec '07

30 Dec '07

Thanks to all. That must be the answer - that the time refers to the date of observation, not a duration. Checking wikipedia, the Greenwich Observatory wasn't founded until 1675 and from memory, the French prime meridian didn't come until the Neapolian era. There probably wasn't a "GMT" in use in 1676. Thanks again. - Kurt _______________________________________________ Sent via CSolutions - http://www.csolutions.net

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Re: Meaning of emersion wrt to Io
by ROBERT MARILYN GRANT 30 Dec '07

30 Dec '07

I haven't posted for a while, but felt I might be able to contribute to this question. I love my 1916 edition of Funk and Wagnalls Dictionary. It retains some old word usages. It gives a common and an astronomical meaning for "emersion", the latter being "The reappearance of a heavenly body after being eclipsed or occulted". So I would agree with Chuck that it means when Io exits from the shadow. I think the word order in the sentence might be confusing, and I think the word "that" was a typo for "than". I think he was referring to a point in time, rather than a length of time. From reading the following sentence "the emersion of the first satellite observed at Paris the 9th of November [1676] last at 5 [hours], 35 [minutes], 45 [seconds] at night, 10 minutes later . . . that had been observed in the month of August", I would rewrite it to say "the emersion of the first satellite observed at Paris last November at 5:35:45 GMT, was 10 minutes later than that observed in the month of August". Bob Grant

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Meaning of emersion wrt to Io
by Kurt Fisher 30 Dec '07

30 Dec '07

I am trying to figure out what orbit event of Io is referred to in the 1677 paper reporting Romer's experiment measuring the speed of light. Romer's estimate was confirmed by the Royal Academey measuring "the emersion of the first satellite observed at Paris the 9th of November [1676] last at 5 [hours], 35 [minutes], 45 [seconds] at night, 10 minutes later . . . that had been observed in the month of August." quoted at Bartusiak, Archives of the Universe at 120. Checking my 2008 RASC Galiean satellite table, I cannot find any combination of Io orbit events that correspond to a period of nearly 5:35:45. Anyone have any idea what this "emersion" refers to? I am working up a star party cheat sheet on Romer's 1676 experiment measuring the speed of light using Jupiter's Moon Io. Romer used the 42.5 hour period of Io's eclipse entry into Jupiter's shadow as his remote timing indicator at Jupiter. 42 hours is an inconvienent measuring period to use for star party purposes, but is easier to measure since the change in light travel time from Jupiter varies by about 15 minutes throughout the year for that 42.5 hour interval. Shorter event periods could be used, such as those mentioned in the Paris confirmation observations above. For star party purposes, I will probably instead try the transit of Io across the face of Jupiter to replicate Romer's experiment. Although these are approximately 3 hour events and the time difference of Io's transit near conjunction and opposition is only about 1 minute, modern videorecording with time signals easily would have that precision - a level of precision beyond Romer in 1677. But if there is an Io orbital event with a 5 hour period, that might be more useable. Again, any idea what the term "emersion" refers to in the above quote from the 1677 report of Romer's observations? - Kurt _______________________________________________ Sent via CSolutions - http://www.csolutions.net

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Re: [Utah-astronomy] Meaning of emersion wrt to Io
by Kurt Fisher 30 Dec '07

30 Dec '07

Thanks, Chuck. I guess "emersion" means "exiting" - the shadow or transit. Granted that the date of opposition of Jupiter probably was completely different in 1676 from July 9 in 2008, but still looking at my 2008 RASC Handbook at page 218 (August) and page 220 (November), I don't see any combination of Io events with a 5.5 hour separation. OcD-EcR is about 3.5 hours. TrI-TrE is about 2 hours. Any other quesses from anyone on what combinations of Io events might give rise to a 5.5 hour separation? - Kurt _______________________________________________ Sent via CSolutions - http://www.csolutions.net

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Current online astronomy broadcasts
by Kurt Fisher 30 Dec '07

30 Dec '07

Some recent Pamela Gay astronomy podcasts - http://www.astronomycast.com/ Episode 68: Globular Clusters (14.3MB) This week we're going to study some of the most ancient objects in the entire Universe; globular clusters. These relics of the early Universe contain hundreds of thousands of stars, held together by their mutual gravity. Since they formed together, they give astronomers a unique way to test various theories of stellar evolution. Episode 66: How Amateurs can contribute to Astronomy (18.3MB) Astronomy is one of the few sciences where amateurs make meaningful contributions to discoveries. Many professional researchers work hand-in-hand with teams of amateurs to make discoveries that just wouldn't be possible without this kind of collaboration. In fact, Pamela regularly relies on dedicated enthusiasts for her data on variable stars. Moore's The Sky at Night http://www.bbc.co.uk/science/space/spaceguide/skyatnight/proginfo.shtml December's Episode - Last Man on the Moon Monday 03 December, 12.45am BBC One On the 14th of December 1972, Captain Eugene Cernan left the moon to return to Earth. He had no idea that, 35 years later, he would still be the last man to have left his footprints on the lunar surface. Dr Chris Lintott travels to the Johnson Space Centre to talk to the Commander of Apollo 17 about his memories of being on the moon. Plus Sir Patrick Moore looks at lunar samples brought back by the astronauts and talks to NASA scientists about what they discovered. - Kurt _______________________________________________ Sent via CSolutions - http://www.csolutions.net

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More on next month's possible impact
by Patrick Wiggins 28 Dec '07

28 Dec '07

Mars Impact Probability Increases to 4 Percent The impact probability for a collision of asteroid 2007 WD5 with Mars on January 30 has increased from 1.3% to 3.9%. http://neo.jpl.nasa.gov/news/news153.html patrick

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