bwilsonchronicle.jpg (24623 bytes)Mars
History of D. S. Magic Eyepiece Eclipse Mars

mars82188215.jpg (91431 bytes)        mars82188440.jpg (184980 bytes) Mars 8/21/88 mars82188355.jpg (144400 bytes) 9-6-03-1140pmstack.jpg (9848 bytes)

Mars Drawings 8/21/88 Disk size 20.40" Ls 256.3  -1.84 magnitude      Mars photo 9/7/03 4:40 UT Disk size 24.53" Ls 255.8 -2.75mag.

During the 1988 Mars Opposition, I had some wonderful views of the polar cap on August 21 during incredibly steady seeing conditions. These drawings made with a Meade 8 inch f 6 reflector on a Byers 58 mount. The last drawing is a close up of the splitting of the polar cap, the so called "Mountains of Mitchel" revealed.

Now 15 years later on 9/7/2003 2:34 am (7:34UT) Mars 24.53 arc seconds in size at mag -2.75 using the same 8 inch f6 2.8 barlow with 5 mm Takahashi eyepiece Central Meridian 351.85 and solar longitude 255.8 Ls, the  Mountains of Mitchel detachment from main cap (Novus Mons) is clearly visible at western limb of polar cap with dark line of separation between main cap and separate cap remnant. Haven't seen this since August 24 1988 with this same telescope.   Photographed blue clouds over SPC at 12:12 am this Sunday morning. Quite a sight to see!

As an aside,  I have been looking for the clear visual separation of the Mountains of Mitchel since solar longitude 250 (ls) and Sunday morning 9/7/2003 2:34 am (7:34UT it was clearly separated, with the white island (Novus Mons) totally clear away from the main cap.  I had suspected the separation the morning before  (Sept 6 7:UT) but could not confirm it due to a unsettled  atmosphere (cold front) which affected seeing conditions here in Houston Texas.

Explanation of terms:

Bright elongated Novissima Thyle, a projection of the south polar cap reaches from the SPC and becomes the isolated Novus Mons ("Mountains of Mitchel"), (from notes from Jeff Beish in Mars Observer's Handbook. Novus Mons or the "M of M" is the remnant of the south polar cap left behind. There are various dark rifts in the cap, such as the Rima Australis, in that Rima Australis is the rift between the isolated Novus Mons and the main cap. In looking at Donald Parker's images of Sept 3rd, it appears that there is still lingering portions of Novissima Thyle attached to the Mountains of Mitchel. The correct spelling is with one "L".

I found this on the website of the Japanese observer: Masatsugu MINAMI "The last but not the least we make mention of the detachment phenomenon of Novus Mons (the Mountains of Mitchell): According to E C SLIPHER, Novus Mons begins to detach from the spc between 250°Ls and 252°Ls, but the Viking image shows that it was still a part of the spc as a peninsula even at 255°Ls. The peninsula is however to be checked around from 230°Ls," Click here for a modern explanation of the Mountains of Mitchel http://science.ksc.nasa.gov/mars/mgs/msss/camera/images/9_17_99_mtchl/

Ormsby McKnight Mitchel. (1809-1862)

The discovery of the Mountains of Mitchel is credited to Ormsby McKnight Mitchel   who in 1850 found a patch of frost near Mars' south polar cap. Mitchel was a professor at Cincinnati College (Now University of Cincinnati)  and founded the Cincinnati Observatory (Our nation's first observatory) in 1842.

He served as its first director. He was instrumental in purchasing the telescope (12 inch lens from Munich) http://www.cincinnatiobservatory.org/merz.html which he used to discover the companion star to bright Antares. Mitchel was an eloquent speaker on astronomy.  He is credited with popularizing astronomy in America, and has been called "The father of American Astronomy."  http://www.cincinnatiobservatory.org/COC/HistoryOfTheObserv.htm

Mitchel was a West Point graduate and  Major General in the Union Army during the Civil War. Ft Mitchell, Kentucky is named for him, the town spells its name with two "LL"s despite the fact that he only had one "L" in his name.  On 10/30/1862 - Ormsby Mcknight Mitchel, US astronomer/Union-general major, dies at 53 of yellow fever.
Here is a picture of him http://www.philaprintshop.com/images/efmitch.jpg

 

 

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