Category: Planetary

I was able to enjoy a rare break in my schedule to observe the planet Mars just past opposition. The night sky was affected by intermittent clouds that eventually obscured the view, but allowed me a brief look at all the same (the limited view did not allow me to use a blue filter). What initially struck me was the amount of cloud activity noted over the Martian disk (especially over the preceding (evening) and following (morning) limbs. The North Polar Cap (NPC) was small but brilliant (10/10) with some dusky (4/10) streaks noted within it. I welcome any comments on my observation.

Date: March 14, 2012
Time (U.T.): 03:30
CM: 209.5ºW
Ls: 83.0º, De 21.6º, Ds 24.6º
Phase 99%, -1.1m, 13.7”
Instrument: 9-inch (23-cm) F/13.5 Maksutov-Cassegrain
Magnification: 310x
Filters: None (IL)
Seeing (1-10): 5-6 (moments of 7), T: 4/6

The North Polar Cap (NPC) was small and brilliant (10/10) with thin, dusky (4/10) streaks noted with it (especially over the preceding half). The NPC was surrounded by a dark (3/10) collar. The NPC remnant Olympia (~210ºW) was noted south of the NPC as a thin, very bright (8/10) streak. The preceding (evening) limb was very to extremely bright (8-9/10) and an orographic cloud (associated with Olympus Mons?) was noted attached to it. The region east (preceding) Elysium (Amazonis/Arcadia/Azania/Phlegra) appeared dusky (4/10) and mottled (fine detail noted when the seeing steadied). A very bright (8/10) cloud was noted noted over Elysium (7/10), possibly Albor, that appeared to extend towards the north over Cebrenia and into Panchaia. Mare Cimmerium appeared dark to dusky (3-4/10) with fine mottling noted within it, especially when the seeing steadied. The fine, dusky (4/10) parallel streak north of Mare Cimmerium, Valhalla, was noted as well. Clouds were noted over Aetheria towards the following (morning) limb (very bright to extremely bright (8-9/10).

A digital image produced in Pixelmator.

Carlos E. Hernandez