March 2008 - Utah-Astronomy - mailman.xmission.com

Selenology Today No. 9 Add - special eclipse issue
by Canopus56 14 Mar '08

14 Mar '08

For those of us who missed the eclipse in Utah due to weather. - Kurt http://digidownload.libero.it/glrgroup/selenologytoday9addendum.pdf ____________________________________________________________________________________ Looking for last minute shopping deals? Find them fast with Yahoo! Search. http://tools.search.yahoo.com/newsearch/category.php?category=shopping

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Obs Rep. U of U Physics Bldg 3-12-2008 9pm MST Rimae Plinius
by Canopus56 13 Mar '08

13 Mar '08

Last night (3-13-2008 3 UTC), I spent a few minutes observing the Moon at a Univ. of Utah Physic's Dept. public telescope night. The Moon was favorably positioned at a pre-spring equinox altitude of 45 degrees. The terminator was running through central Mare Serenatitus west of C. Plinius at about E19 long and at a low-solar angle of about 6.5 degrees. While looking along the terminator for interesting objects, I was suprised to see the dark mantle at the southeastern end of the Mare Serenitatis Basin - between Promontorium Archerusia and Mons Argaeus to show really striking contrast. It looked like there was a dark triangular kitchen knife blade above C. Plinius and north of Rimae Plinius. Initially, I took the dark patch for a shadow but then remembered mineral differences between the titanium poor lava flows at the depressed center of the mare and older more titantium rich grabens around the edges of the mare. (See LPOD 8-27-2004, http://www.lpod.org/archive/LPOD-2004-08-27.htm , LPOD 2-17-2007 http://www.lpod.org/?m=20070217 ). The dark mantle around the edges of Mare Serenitatis are well known and usually seen at the full Moon as an albedo effect shown in the 8-27-2004 LPOD. But last night under low angle illumination, the albedo effect was much more intense and triangular shaped with defined edges than normal. I wasn't sure if I was looking at darker shadow due a topography grade or a very favorable low angle illumination that enhanced the albedo darkness of the dark mantle garben just north of Rimae Plinius. See Rukl 24 and LAC I489. Or was it a combination of both? The telescope docent at the U. Physics Dept., Paul Ricketts, graciously interrupted his routine to snap some quick fits images using a DSI Pro II on a Meade 14 inch SCT. The attached processed image that I prepared is not up to modern lunar imaging standards (compare to LPOD 5-11-2007, http://www.lpod.org/?m=20070511 of C. Plinius by Simon Kidd), but it does convey the enhanced albedo of the Rimae Plinius dark mantle region that I saw on the 13th. The right-hand side is a Clementine near infra-red image from USGS Map-A-Planet. http://gallery.utahastronomy.com/main.php?g2_itemId=11038 http://gallery.utahastronomy.com/main.php?g2_itemId=11042 Other parts of the image can be taken to argue ambiguously for and against a mineral cause of the darker albedo north of the R. Plinius graben. The outline of the dark region is similar to its geologic extent seen on LAC I489. The region to the west of Dorsum Aldrovandi is made of the same geologic materials as those of the R. Plinius graben, but in the image the D. Aldrovandi region does not show a contrast difference with lighter lava flows in the center of the mare under an only slightly higher solar illumination angle. Conversely, the dark mantle deposits of the Littrow Valley fan appear darker under that same higher illumination angle. I did some post-session checking to resolve in my mind whether the heightened dark albedo was the result of 1) a shadow from topography or 2) just the low-Sun angle reflecting off the dark mantle surface or 3) some combination of the two. The USGS shaded relief map elevation values for this area were ambiguous, as where the ULCN 2005 control points plotted using LTVT. I checked a USGS DEM created from the ULCN points and plotted a profile north south across the Rima Plinius graben between C. Plinius and C. Dawes. The DEM profile showed a consistent 400 meter slope over 200 kilometers with a ledge corresponding to the graben shown north of C. Plinius and south of Dorsa Nicol in Simon Kidd's high-resolution high-detail image (LPOD 5-11-2007). Comparing the three references (my image, the USGS DEM, and Kidd's image), I decided that the enchanced dark albedo that I saw could probably be attributed to mostly a topographic shadow. In any event, the next time the terminator is around East 19 degrees at a lunar age of 5.4 days, look for this enhanced albedo effect in the southeastern Serenitatis Basin. It is really quite striking and it's dramatic effect - well-beyond the normal contrast of the Plinius dark mantle region normally seen at full Moon - is not properly conveyed by the attached image. - Canopus56 Direct image links: Unlabeled http://gallery.utahastronomy.com/main.php?g2_view=core.DownloadItem&g2_item… Labeled http://gallery.utahastronomy.com/main.php?g2_view=core.DownloadItem&g2_item… ____________________________________________________________________________________ Never miss a thing. Make Yahoo your home page. http://www.yahoo.com/r/hs

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Re: [Utah-astronomy] Colorful double star observing lists
by Canopus56 13 Mar '08

13 Mar '08

Tyler wrote: > Those lists will be great, especially the one > that targets colorful doubles that cross the > zenith. Thanks again for taking time > to respond! :) Tyler Your're welcome. To be clear, the Belmont Society based list covering from 90 to -38 dec has been used extensively - as has Mullaney's Celestial Harvest. I haven't personally looked at all of them but have always felt the list was strong in terms of reliability. The Hass book extraction I view as experimental. Again, I am working through that extracted list (I started last summer) for the 41N zenith and haven't personally seen all the targets. Hass' book is basically a compilation of several double star observing lists from the 1800s and 1900s. It wasn't clear to me from reading her book whether she actually looked at all 2,400 double stars. I didnot include Hass' color tag descriptions when building a subset for the 41N zenithal stars. My plan was to add the color descriptions in Astroplanner as I made an observing note for each target. For Hass' color tags, in fairness, you'll have to buy her book, which is about $25 from SkyPub. So, I'd view the 41N zenith list as a collection of potential targets involving double stars with color contrasts. If some don't pan out, please get me some leeway on the intended nature of list. Happy imaging - Kurt __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com

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Colorful double star observing lists
by Canopus56 13 Mar '08

13 Mar '08

Way back on Feb. 10, Tyler asked: > I would like to try imaging a few double stars > at some point. Do you have any suggestions for > colorful doubles that might be photogenic? and I offered to supply two of my personal resource lists for colorful double stars. The two lists are linked off this page: http://members.csolutions.net/fisherka/astronote/plan/coldoubles/ColorContr… My apologies for the delay in assembling and posting the follow-up lists. I was distracted on a computational double star project. Enjoy, Peace - Kurt ____________________________________________________________________________________ Looking for last minute shopping deals? Find them fast with Yahoo! Search. http://tools.search.yahoo.com/newsearch/category.php?category=shopping

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Obs Rep - UofU Star Party 3-12-2008 Lunar
by Canopus56 13 Mar '08

13 Mar '08

Had an enjoyable night using a C8 at the UofU South Physics Building. I had one of the best views of the proyclastic deposit and surrounding Rimae Plinius at the south end of Mare Serenitatis and the mare lava flow boundaries between Serenitatis and Tranquillitatis. The color contrast was really pronounced due to the low-illumination angle. The docent, Paul Ricketts, took some images for me that I am still processing. - Kurt http://the-moon.wikispaces.com/Rimae+Plinius http://www.lpod.org/coppermine/displayimage.php?album=search&cat=0&pos=2 http://www.lpod.org/coppermine/thumbnails.php?album=search&type=full&search… http://www.lpod.org/coppermine/displayimage.php?album=search&cat=0&pos=6 ____________________________________________________________________________________ Looking for last minute shopping deals? Find them fast with Yahoo! Search. http://tools.search.yahoo.com/newsearch/category.php?category=shopping

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ISS video
by Patrick Wiggins 13 Mar '08

13 Mar '08

Nice amateur video of ISS: http://www.youtube.com/watch?v=Rf9opkXX-D4 patrick

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Bino sale (relay from Chuck)
by Patrick Wiggins 11 Mar '08

11 Mar '08

Chucks still off the list for a while but asked I let you bino users out there know that the West Valley Big 5 store has Barska 15x70mm binos on-sale for $49.99. patrick

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Over 400k
by Patrick Wiggins 11 Mar '08

11 Mar '08

The total number of charted minor planets has now passed the 400,000 mark. As of this afternoon the number stands at 401,950 (and climbing). patrick

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It's Okay Pluto
by Ann House 11 Mar '08

11 Mar '08

T-shirts anyone? http://www.snorgtees.com/itsokaypluto-p-460.html -A

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Wolf Creek Placemark Test
by Dave Bennett 09 Mar '08

09 Mar '08

Hey fellow stargazers, Would someone who's running Google Earth on a PC do me a favor and email me directly so I could send you a Google Earth placemark for the Wolf Creek observing site for a test run. Just checking to make sure the Google Earth .kmz file works cross platform. I'd include it here but wasn't sure if an email with attachments would bounce. Thanks! Dave Bennett P.S. I'm thinking about putting together a Google Earth placemark 'tour' package for some of the popular observing sites here Utah. Please let me know if any of you would be interested in such a thing and also if you have suggestions for the list. The tour could begin with a 'street level' view of Patrick's observatory ;-) db

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