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

Delta cosmic ray observatory
by Patrick Wiggins 04 Jul '07

04 Jul '07

I flew down to the Delta area today in hopes of seeing the new cosmic ray observatory. I expected to find a bunch of detectors laid out all over the desert floor for kilometers in all directions. But what I found was this: http://users.wirelessbeehive.com/~paw/temp/COSMICRAY01.JPG Either I was looking in the wrong place or they are not as far along as I thought. One thing's for sure though. Once it's finished it's going to be big: http://web.utah.edu/unews/news_images_2004/jan/TelescopeArray.jpg pw

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Genesis II
by Kurt Fisher 03 Jul '07

03 Jul '07

Genesis II, a balloon habitat that is a prototype for a space hotel, successfully launched and is in orbit. http://www.bigelowaerospace.com/out_there/genesis_II_first_pics.php Today's Spaceweather.com (7/3/2007) includes amateur imaging of the test hotel, which reflects at 3 mag. http://spaceweather.com/ Ken Fetter's video of Genesis II passing Vega http://spaceweather.com/swpod2007/02jul07/genesis2.wmv CalcSky is showing an early morning overpass tonight at around 2:45am: Wednesday 4 July 2007 2h46m19s [MDT] GENESIS 2 (31789 2007-028-A) Appears 2h40m14s 8.2m az:328.0° NNW Disappears 2h46m19s 3.7m az: 9.6° N h:72.0° Where does one apply to be the room cleaner? - Kurt _______________________________________________ Sent via CSolutions - http://www.csolutions.net

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Obs Report: Venus-Saturn conjunction 6-30 at SPOC
by Kurt Fisher 03 Jul '07

03 Jul '07

A couple of other science-ee notes for star parties this week and Venus-Saturn: 5) Inferior planets exhibit maximum enlongation with respect to a superior planet; Superior planets do not show maximum enlongation. Venus past maximum enlongation about a month ago. Venus will reach maximum brightness in about a week. Maximum elongation means the apparent position of Venus (from Earth's orbit) is the furthest that it gets from the Sun. For the next couple months, Venus will appear to travel closer to the twlight setting Sun. Near maximum elongation, Venus closer to Earth. The combination of its crescent phase and proximity to the Earth result in its maximum brightness. Because it is a superior planet, Saturn does not display maximum elongation relative to the Earth. Conversely, if the Cassini orbiter were to look back at Earth and Venus, both would be near maximum elongation as seen from Saturn. The JPL/NASA solar system planectia can be used to display a "from above" image of the solar system to show relative planet positions. http://space.jpl.nasa.gov/ Display the "Solar System" from "Above" and set the "field of view" to 2 degrees. A 3-D diagram can be generated using the NASA-JPL small body orbit simulator. http://neo.jpl.nasa.gov/orbits/ Enter "Vesta" in the object box to generate a suitable display. Suitable diagrams also are published each month in Sky & Telescope. 6) There unmanned orbiters at both Saturn and Venus returning images. Enjoyment of Earth-based visual observing of Saturn and Venus can be enhanced by follow-up viewing of current oribter images of those planets. Saturn - Cassini http://ciclops.org/index.php?flash=1&flash=1&js=1 http://saturn.jpl.nasa.gov/home/index.cfm http://www.esa.int/SPECIALS/Cassini-Huygens/index.html Venus - Venus Express http://www.esa.int/SPECIALS/Venus_Express/index.html NASA Cassini image returns are closer to real time. Like other ESA missions (SMART-1), Venus Express image postings are made infrequently, but are available. Here's an amateur image by Rob Johnson (posted on sci.astro.amateur) of Saturn and Venus together that illustrates the ecliptic plane note (item no. 3) up-thread: http://www.whim.org/nebula/astro/vsalign20070630.html - Kurt _______________________________________________ Sent via CSolutions - http://www.csolutions.net

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Off-topic: Bears, fire prohibitions and Wasatch campgrounds
by Kurt Fisher 02 Jul '07

02 Jul '07

Usually, the Wasatch front campgrounds are stuffed full on the July 4 weekend. This weekend, the one campground (Affeleck) I went to was empty - literally - except for me and one other family. I guess that unfortunate incident with the bear in American Fork a couple of weekends ago, coupled with the statewide fire prohibition drove everyone away. It made for a nice twilight, with a few deer walking down to the creekside 30ft away from me, for their evening drink. - Kurt _______________________________________________ Sent via CSolutions - http://www.csolutions.net

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Adirondack? (Venus/Saturn tonight)
by Naz_David 01 Jul '07

01 Jul '07

Patrick, I have had no problems with them. Jim is always good for a nice telephone chat. In fact, I have just purchased a Stellacam III from them and everything has gone fine. I am upgrading from a Stellacam II with TMS, which is listed on Astromart at the moment :) Some on the group have seen it in operation at Bryce. Cheers David Has anyone here had any dealings with a company called Adirondack Video Astronomy? If so I'd like to hear if it was a good or bad experience.

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Adirondack? (Venus/Saturn tonight)
by Kurt Fisher 01 Jul '07

01 Jul '07

Bought a couple of items from them about two years ago when it was called something like Adirondack Bird and Telescope. Had no problems in the two transactions and received one quick response to an email request. I have no current experience with them. - Kurt _______________________________________________ Sent via CSolutions - http://www.csolutions.net

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Obs Report: Venus-Saturn conjunction 6-30 at SPOC
by Kurt Fisher 01 Jul '07

01 Jul '07

A line of five scopes plus the Bogan refractor was at SPOC last night for the Saturn Venus near conjunction. Members included Bruce G., Patrick W., Roger Butz, Wayne, Larry Holmes, and myself. This was a laid-back night with light public attendence. In a single low-magnification e.p. view (50mm 2" e.p. on a 5 1/2 inch 1120mm refractor), Venus and Saturn presented a great asthetic view. Just past sunset, the Earth's terminator passed overhead, mirroring the terminator on Venus. As the sky darkened, Saturn, Titan and Venus visible in a brighter twilight sky. Using an light blue (80A) filter at higher magnification, some detail could be seen in Venus's terminator, but the arcsec resolution of 5 1/4 inch apeture combined with low-altitude sunset atmospheric seeing was insufficent to resolve any other cloud detail. The Saturn and Venus conjunction also showed a number of basic solar system planet relationships between inferior and superior planets that will repeat again this evening: 1) Inner planets have a phase; outer planets do not. The inner planet Venus showed a sharp crescent phase; Saturn presented no distinct illuminated fraction. But at conjunction, both planets are nearly in the same visual line from Earth. Mars, which was not observed on this evening, rises in the early morning hours and does show a phase. See story << http://www.space.com/news/070627_mars_storm.html >>. Because both Venus and Saturn are nearly on the same sight line from Earth, the initial common sense impression is that they should both show a phase. To see a distinct illuminated phase, a planet must be inferior to the Earth or slighty outside its orbit. Each planet's Earth-planet-Sun geometry varies due to their relative distance from the Earth. The ratio of the diameter of the Earth's orbit (1 A.U.) to Saturn's orbit (9.5 A.U.) is so small that the Earth never reaches an orbital position where Saturn has a significant illuminated fraction. The Earth-Venus-Sun phase angle is around 108 degrees, but the Earth-Saturn-Sun phase angle is only about 4 degrees. If the Cassini spacecraft was pointed looking back towards Earth, its wide angle images would show both the crescent shapes of Venus and Earth. Although no Cassini image exists, a concept simulation can be made using the JPL/NASA Solar System Simulator << http://space.jpl.nasa.gov/ >> and setting the "field of view" option to 0.2 degrees. 2) Distance and physical size relate to apparent size and brightness. Saturn (1.0 mag), although much more massive than Venus, had an apparent brightness much lower than Venus (-2.8 mag). Saturn is 10 times larger than Venus but is about 30 more times distant than Venus. ( Radius: Saturn 60.2km / 6.0km ). (Distance a.u.: (9.5 a.u. - 1.0 a.u.) / ( 1.0 a.u. - 0.7 a.u.) = 8.5 / 0.3 = ~30 ). Saturn orbits at 1,429M km; Venus at 108 M km; and the Earth at 149.5M km. Because of its relative nearness, the smaller diameter Venus had an apparent linear brightness of about 28 times brighter than Saturn or 3.8 times as bright on the magnitude scale. ( 1127.2 / 34.0 = 28 ; 1v - (-2.8v) = 3.8v ). Because of its relative nearness, the smaller radius Venus (6.0km) had a relatively larger apparent diameter ( radius 6km, 32") as compared to the more distant, but much larger, Saturn ( radius 60.2km, apparent diameter 17" ). 3) Some planets are tilted with respect to the ecliptic; others are not. Saturn, like the Earth is tilted on its rotation axies relative to the ecliptic. Saturn is tilted about 27 1/2 degrees to ecliptic as compared to the Earth's 23 1/2 degrees. Because of its cloud cover, Venus has no visually discernable tilt, equator or rotation axis. From radar studies is is known to be about 177 degs, or nearly aligned with the plane of the ecliptic. Usually observers do not perceive Saturn's tilt relative to the ecliptic because there is no visual reference of the ecliptic plane in the e.p. view. The rings provide a physical reference of the tilt of Saturn relative to the Earth. At this conjunction, mentally drawing a line perpendicular to the cusps of Venus's terminator provides an ecliptic reference line in the e.p. view and enables the observer to visually appreciate the tilt of Saturn's equator relative to the ecliptic. If Venus and Saturn cannot be seen in the same e.p. view, a reticule e.p. can be used on Venus to set the near ecliptic line and then the e.p. can be panned over to Saturn. The Earth's tilt with respect to the ecliptic can be demonstrated by referencing the angular distance between due west and the point of the setting Sun in your local horizon system. 4) Because inferior inner planets move around the Sun relatively faster than the Earth and the outer planets, conjunctions between outer and inner planets are relatively more frequent. Inferior Venus conjunctions with the outer planet Saturn within 4 degrees will occur 11 times in the next 10 years. Inferior Venus conjunctions with the outer planet Saturn within 1 degree will occur 5 times in the next 10 years: 7/2/2007 00h 0.77 degrees 8/13/2008 19h 0.24 degrees 10/13/2009 15h 0.56 degrees 11/27/2012 05h 0.56 degrees 1/9/2016 03h 0.09 degrees In contrast, there are no conjunctions between outer planets Saturn and Jupiter in the next 10 years. Mars and Saturn will have four conjunctions less than 4 degrees in the next ten years. On 7/11/2008 06h, Mars and Saturn will be 0.69 degrees apart. In North Amerian, they will be low (~20 deg alt) and about due west, just after the Sun sets. - Kurt P.S. - Somewhat spooked by email traffic regarding the sprinkler situation at SPOC, I packed up before the potential 11:03 pm turn-on of the sprinkler system. The spector of smoke rising out of my $1,200 water-soaked EQ-6 mount is cause for legitimate paranoia. However, the sprinklers did not turn on. Additionally, in apparent overcompensation, the sprinklers appear to have not been coming on regularly, resulting in a partial lawn die-off at SPOC. In reviewing the matter with Patrick, it appears that the sprinkler system problems can be traced back to a change in grounds personnel at the park service district offices. The groundsman for many years, who was very supportive of SPOC, has left the district. His replacement has a more rigid view about who should have a voice in setting the watering schedule at SPOC. This is being resolved through communications with district management. The sprinkler system problem appears to be a minor personnel matter, internal to the park service district, that will resolve itself in the ordinary course. Conversely, there is now a great large green road sign at the park entrance marked "observatory" that makes it easier for the public to find the right-turn off for SPOC. I assume that we have the service district to thank for the sign. Clear skies - Kurt _______________________________________________ Sent via CSolutions - http://www.csolutions.net

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Saturday Night's Harmons Star Pary
by Ann House 01 Jul '07

01 Jul '07

We had a good turnout for last night's impromptu star party at Harmons in Midvale. There were at least 15 scopes and dozens of visitors. There were many kids, families, and couples. I am sure that many there would not be the kind who would venture out to SPOC to see the skies, so I am reminded of the need for our parties in town. Thanks to all who came for the evening with their telescopes, and for the great visits and conversations we had among SLASers. We are a great bunch of people and we enjoy the socializing almost as much as showing visitors the planets. Or socializing more?? Anyway, it was a fun evening. -A

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Adirondack? (Venus/Saturn tonight)
by Patrick Wiggins 30 Jun '07

30 Jun '07

Has anyone here had any dealings with a company called Adirondack Video Astronomy? If so I'd like to hear if it was a good or bad experience. Thanks, Patrick p.s. Remember that Venus and Saturn are at their closest this evening. I saw them through one of Bruce Grim's wide field scopes last night and seeing the huge crescent Venus and the much smaller ringed Saturn was impressive. Should be even more so tonight.

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Gegenschien ephemeris for Salt Lake City vicinity
by Kurt Fisher 30 Jun '07

30 Jun '07

Id's favorable opportunities to view the gegenschien from a dark sky site. All local times are in Mountain Standard Time (MST). http://members.csolutions.net/fisherka/astronote/astromath/2007GegenschienE… Enjoy and Clear Skies! - Kurt _______________________________________________ Sent via CSolutions - http://www.csolutions.net

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