|
|
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". 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.
|