Fremont Peak Observing, July 26-27th, 2003

by Peter Natscher

Observing with my AP 10" Maksutov-Cassegrain telescope last night up at Fremont Peak in the SW Lot was more than satisfying for my H400 object logging and drawing. We were surprised with more of the southerly monsoon cloudiness that cut down on my H400 observing time. I now have only 20 objects to go for completion of my H400 observing and drawing project. I do recommend this kind of observing project; manually finding, spending time observing, and sketching deep sky objects, to all who are looking for a new observing project.

Later on after midnight, the few of us remaining were treated to very better Mars' views after the cloudiness had cleared and the seeing settled, especially during 1 am to 3:30 am. I was observing the ochre and gray-green planet capped with a gleaming white southern polar cap with my binoviewer using 10mm Zeiss Ortho's and planetary filters. The seeing afforded me to use 420X with this setup which easily kept the Martian contrast high most of my viewing time. I recommend these planetary filters (Baader Planetary Filters from Astro-Physics) cut the bright glare down without changing the delicate planetary surface colors too much and they added contrast to the finely mottled green-gray surface features of this now large-looking planet.

During this four-hour observing period, Mars was positioned to us with a CM of between 90° to 40°. From east to west on the planetary disk, I clearly saw: Mare Siremun, Amazonis, Nix Olympica, Aonius Sinus, Mare Erythraeum, Solis Lacus, Aurorea Sinus, Cryse, Niliacus Meridiani Sinus. The south polar cap was very bright white with ragged edges bordering Mare Australe and had a an northward extending and brighter spot at the Argyre location (CM 45°). The fine long and pointed feature extending northward out of Aurorea Sinus was awesome. Argyre was noted as being prominently brighter within the darker gray-green Mare Erythraeum region. The northern polar limb showed a nice blue-white atmospheric haze which extended about 45° wide along the limb. This interplay was a beautiful contrast to the neighboring ochre plains areas and the gray-colored Niliacus Lacus region.