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

Star Party Presentation Cheat Sheet - Older Low-Metallicity Globular Clusters for Aug Sept
by Naz_David 15 Sep '07

15 Sep '07

Thanks Kurt, this is great stuff and the other content on your ftp is also really interesting. What do you do for a crust? If not Astronomy related then you are a busy lad! Cheers David

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SPOC
by Chuck Hards 14 Sep '07

14 Sep '07

Just a heads-up to SPOC users; someone has placed a padlock on the gate as Erik and I discovered last night. I have already emailed Bruce about it. Skies were very bright last night and the seeing soft, probably due to all the smoke in the air from distant wildfires. Planetary nebulae were relatively unaffected; especially with my OIII filter, but galaxies suffered. M27 is a magnificent sight in the 32" with OIII filtration and medium powers. One guest observer called it "almost 3-D" in appearance. We also managed some so-so views of Uranus and Neptune. The color difference was easily noted with Uranus a grey-green in tint, and Neptune more of an azure hue.

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Star Party Presentation Cheat Sheet - Older Low-Metallicity Globular Clusters for Aug Sept
by Kurt Fisher 13 Sep '07

13 Sep '07

Star Party Presentation Cheat Sheet - Older Low-Metallicity Globular Clusters for Aug Sept This is to announce a star party presentation cheat sheet for use at astronomy club star parties. http://members.csolutions.net/fisherka/astronote/tours/AugGlc/StarPartyAugG… Using a GOTO mount in a series of quick slews around Cygnus, show three of five older low-metallicity globular clusters and one younger high-metallicity globular cluster by increasing distance and compare their relative visual angular and physical sizes. Explain the high concentration of low-metallicity RR Lyra variables in these clusters. The cheat sheet includes an observing list, a table of physical parameters, finder charts, images, background information and suggested discussion topics. - Kurt _______________________________________________ Sent via CSolutions - http://www.csolutions.net

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Kaguya Launch at 7:30pm MDT
by Kurt Fisher 13 Sep '07

13 Sep '07

Japan's Kaguya lunar orbiter is scheduled for launch at 7:30pm MDT tonight. A web broadcast can be viewed at: http://www.jaxa.jp/countdown/f13/index_e.html Kaguya (fna Selene) is a major multi-spectral lunar mapping mission on the order of the Mars Reconnaissance Orbiter. Its main visual imaging camera has a 10 meter resolution. Unlike SMART-1, a miniaturized satellite testbed, Kaguya is 3 ton behemoth measuring 2.1m x 2.1m x 4.8m. Kaguya is jam packed with the great array of multispectral imagers. http://www.selene.jaxa.jp/en/index.htm By comparison, SMART-1, a miniaturized satellite testbed, was a 287kg 1 meter cube and its main visual camera had an 80 meter resolution. Modern advanced amateur lunar imagers typically reach 250-300 meter resolutions. One of the objectives of the mission is to create a full nearside map of the Moon down to 20 meter resolution precision. - Kurt _______________________________________________ Sent via CSolutions - http://www.csolutions.net

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Re: [Utah-astronomy] New images from Tremonton
by Wayne Sumner 13 Sep '07

13 Sep '07

WOW!! The quality of your work is amazing. You have an impressive equipment list, too. Would you be willing to offer me some advice on what I should purchase for the 12" Nishimura telescope that we are building a roll-off roof observatory for here on the Northridge High School campus? Thanks, Wayne A. Sumner Math/Physics/Astronomy/Engineering Boy's Tennis Coach Northridge High School Davis School District (801) 402-8610 >>> "Tyler Allred" <tylerallred(a)earthlink.net> 09/12/07 6:22 PM >>> Hi all, I have been absent for some time now, but I finally got a chance to do a little imaging and managed to complete three new images. Here are links to the small versions. larger version are available by clicking on the pics. The Iris Nebula http://www.allred-astro.com/subpage47.html The Pleiades http://www.allred-astro.com/subpage49.html M33 - The Pinwheel Galaxy http://www.allred-astro.com/subpage51.html My new home in Tremonton has pretty dark skies and is a really big improvement over Orem! I hope someone enjoys viewing these images. Let me know what you think. Cheers, Tyler Tyler Allred President Allred Restoration, Inc. 5725 W 12000 N Tremonton, UT 84337 801-358-1868 cell <mailto:tylerallred@earthlink.net> tylerallred(a)earthlink.net _____________________________________________ _______________________________________________ Utah-Astronomy mailing list Utah-Astronomy(a)mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy Visit the Photo Gallery: http://www.utahastronomy.com

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Off the boards
by Chuck Hards 12 Sep '07

12 Sep '07

I have changed my utah-astronomy list preferences to the "no mail" option effective immediately. My email address will still show up as a subscriber, but I will not be receiving posts until such time as I turn it back on. Might be soon, might be months. If you want to contact me, please use my Yahoo address or office email address, as I only use Gmail for the astro list and won't be checking it. The phone works even better. See you under the night sky!

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Solar min
by Chuck Hards 11 Sep '07

11 Sep '07

A lunch time look showed the solar disk to be absolutely featurless in white light, at 16X. If anyone has Ha or a PST, a description of the solar disk at that narrow bandpass is appreciated.

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Observing request (and a "just for fun")
by Patrick Wiggins 10 Sep '07

10 Sep '07

This might be a fun project for those who like to observe variable stars: Request to monitor PQ Andromedae for HST observations http://www.aavso.org/news/pqand.shtml And, off topic, but fun none the less: Talk Like a Pirate Day http://www.talklikeapirate.com/ pw

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Photographing the gegenschein
by Kurt Fisher 10 Sep '07

10 Sep '07

Kim wrote in a prior thread: > At the group site in Capitol Reef I/we easily saw > the gegenschien at the anticipated position. Thanks, that's wonderful. I was looking for confirmation that the gegenschein ephemeris works. Looks like my ephemeris spreadsheet works. Thanks, greatly. > I plan to go up to the Skyline Drive this > week to try and photograph the gegenschein from there. I don't know the sky there. Hopefully, it will be dark enough. > I tried to also capture the gegenschien but I was > never sure that what I saw on the film wasn't the > center-image brightening associated with fast camera > lenses. I'm hoping that a digital image will help > avoid this problem. I understand from Covington's book that the confirmation trick is to take two pictures separated by time but centered on the same alt-az point. If the spot moves with the sky background - that's the gegenschein. > Should Gegenschein be capitalized for some reason? > I've seen it both ways. It's german spelling. In german, nouns typically are captialized. I am not sure of the proper english grammer rule - whether capitalization of words borrowed from other languages should be honored. In english, "the region of counterglow" would not be capitalized. I've also been misspelling it. It's "schein" not "schien". - Kurt _______________________________________________ Sent via CSolutions - http://www.csolutions.net

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RE: [Utah-astronomy] Bryce Canyon trip - Look for gegenschien please
by Kurt Fisher 10 Sep '07

10 Sep '07

Kim wrote: > At Bryce Canyon NP in June I had an interesting > conversation with John Dobson regarding the > gegenschein. I've always understood that > the source of both the zodiacal light and gegenschein > is sunlight reflected from interplanetary comet > dust. In his characteristic way, John said, "NO!" > According to John, the source is actually > reflected sunlight from dust-size fused silica (glass) beads > blasted from the surface of the Moon by impacts. It is possible that I've missed an article, there doesn't seem to be much support for this statement in the journal literature. There are two possible causes: (1) dust in the interplanetary medium from comets and asteriod collisions and (2) dust from lunar impacts. Supporting evidence is stronger for a cometary and asteriod source - graphically illustrated by this year's earlier apparition of the once-in-forty year "great" Comet McNaught. http://antwrp.gsfc.nasa.gov/apod/ap070122.html. I. Possible Cause A: Kordylewski clouds That lunar libration clouds (Kordylewski clouds) at the Earth-Lunar L4 (leading) and L5 (trailing) points might exist have been speculated for some time. ( http://en.wikipedia.org/wiki/Image:Lagrange_points_Earth_vs_Moon.jpg ) The Earth-lunar L4 and L5 points are in the moving reference frame of the Moon's orbit. In the Earth-Moon libration system, points L2 (behind the Moon) and L1 (between the Earth and the Moon) would not be expected to be visible. I understand L3 is too unstable to be expected to hold dust particles. Kordylewski clouds are elevated areas of brightness either within the gegenschien or adjacent to it. See: Kordylewski 1961 http://adsabs.harvard.edu/abs/1961AcA....11..165K Krumm 1968 AAVSO http://www.homestead.com/cleopanther/files/AAVSO.pdf Recent dynamical modeling of the L4 and L5 points (Jorba 2000, A&A 364:327-338) indicates that such stable orbital regions can persist for up to 1,000 years. Freitas's studies related to a SETI search are often cited as failing to physically confirm these credible lunar libration cloud sightings. See - Freitas 1980 (in context of SETI search) http://www.rfreitas.com/Astro/SearchIcarus1980.htm Freitas 1983 (in context of SETI search) http://www.rfreitas.com/Astro/SearchIcarus1983.htm Freitas stated that his work could not rule-out the existence of micrometeorite clouds. In summary, there is no recent visible, radar, radio or infra-red confirmation of the existence of Kordylewski lunar libration dust clouds. II. Potential source B: Comets and asteriods Satellites with dust detectors including Helios, Pioneer 9, Galileo, Ulysses and Cassini have been used to trace the interplanetary dust medium out to about 3 A.U. It is not a local Earth-Moon phenomena. The dust disk has been imaged by Skylab in the 1970s, IRAS in the 1980s and by Clementine in the 1990s. IRAS satellite images from the 1980s revealed subbands of heightened illumination within the smooth zodicial light disk. ( Skyes (2005?), Fig. 3, http://www.lpi.usra.edu/books/CometsII/7024.pdf ). Through modeling, these bands are associated with the orbital paths of: a) Jupiter family comets with an inclination of 7 degs to the ecliptic. b) Halley family comets with an inclination of 33 degs to the ecliplitc. c) Istropically distributed Oort comet clouds. Hahn 2002 ( http://arxiv.org/abs/astro-ph/0204111 ). Hahn's modelling attributes 89% of the volume of interplantary dust within 1 AU to cometary sources. High altitude capture of interplanetary medium dust indicates their structure and composition is consistent with cometary or asteriod origin. See Sykes as Fig. 4. III. Contra-evidence: Lunar sodium atmosphere Spectroscopic studies of the Moon and anti-lunar point made since the mid-1990s indicates that there is a significant sodium atmosphere surrounding the Moon out to 2 or 3 lunar radii. The density of the thin sodium lunar atmosphere varies with the intensity of meteor showers such as Leonid storms in 1998 and 2001. See - Potter 2001 http://adsabs.harvard.edu/abs/2000JGR...10515073P Smith, SM 1999 http://adsabs.harvard.edu/abs/1999GeoRL..26.1649S When the Moon is between the Sun and the Earth, this sodium atmosphere is blown away from the Moon and around the Earth. The sodium wind "tail" has been imaged spectroscoptically at the anti-lunar point by professionals using a 1.2 meter telescope. Smith 1998. (It is not clear whether this sodium atmosphere could be detected by amateurs using modern CCD equipment.) The sodium gas is simply easier to detect - as compared to lunar micrometeorites or dust. Presumably, the impacts that increase the density of the sodium lunar atmosphere also replenish any lunar micrometeor dust in the Earth-Moon system. But the extent and volume of such replenishment is not known. Kim, in conclusion, there is little support in the journal literature that gegenschien is principally caused by reflection from lunar meteor dust. The weight of the literature is that the dust off of which gegenschien reflects has its source in comets, asteriods and the Oort cloud. This does not rule out contributions to gegenschien from lunar micrometeor dust or Kordylewski lunar libration dust clouds. Kordylewski clouds are probably a transient phenomena and without more continuous monitoring, it is unlikely their frequency and causes will be found in the near future. Part of NASA's return-to-the-Moon project is a professional program, using two dedicated RCT 14" robo-scopes to continuously monitor lunar meteor impacts on the Moon. ( http://www.nasa.gov/centers/marshall/news/lunar/photos.html ) Amateur members of the ALPO has been reporting such impacts for years. ( http://www.lpl.arizona.edu/~rhill/alpo/lunarstuff/lunimpacts.html ) The NASA program site listed above provides instructions for amateurs on how to image for lunar meteor impacts and software to automatically scan AVI files for meteor impact flashes. The ALPO site ( http://www.lpl.arizona.edu/~rhill/alpo/lunarstuff/AnnualShowers.doc ) includes a list of favorable meteor showers that might produce impact flashes. The next favorable dates for 2007 are Nov. 6, Nov. 18 (Leonids) and Dec. 14 (Geminids). - Kurt _______________________________________________ Sent via CSolutions - http://www.csolutions.net

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