24 August 2008

Lunar Limb - Daylight Observation

Date: 24 August 2008
Time: 17:18 - 17:33 U.T.
Telescope: 80mm f/5 achromat
Magnification: 70x
Filter: Polarizing
Seeing: Fair - Good
NELM: Daylight
Temperature: +85F (+29C)
Wind: Calm
Transparency: Very Good (cloud-free sky


The above sketch shows two lunar mountains that were silhouetted against the darker sky background. North is up. Lunar East (preceding) is to the left in this mirror-reversed view. The sketched region is at 90 degrees west longitude and approximately 12 or 14 degrees south latitude. The moon was a fat, waning crescent at the time of the observation.

Not shown in the sketch is Lacus Aestatis which was seen as a dark patch to the left of the lower mountain peak beyond the sketched region. A very rough, larger scale sketch was made to facilitate finding this region on a lunar map. That sketch showed Lacus Aestatis, Cruger, Grimaldi, and Riccioli all as dark patches.

The sun was still spotless today. I used the 80mm refractor at 24x. A glass, white-light solar filter covered the front of the telescope. The filter gave the sun a soft, golden, peachy color. There was something aesthetically pleasing about observing a spotless sun through a telescope with one's own eyes.

No comments: