Thursday, June 12, 2008

Lunar Mare Imbrium

Date: 12th June 08, Thursday
Observation Time: 9:15pm to 10:30pm (1:15 hrs)
Location: SD Home, CA
Weather: Seeing was excellent. Clouds started coming over afterwards.. so was hard to focus with high magnification.

Highlight of the Night: Mare Imbrium and Crater Sarabhai

Phase of the Moon: 10th day after new moon. waxing gibbous with 79% of the Moon's visible disk illuminated.

Initially took me a while to figure out where is the terminator lying in the map. I thought that it is in Mare Serentatis, but it was in Mare Imbrium. Good part is figuring out N-S-E-W in the eyepiece was easy. so looking into the map was easy afterwards.

Most of the observation was with 184x magnification, 12mm with 2x Barlow. Occasionaly I switched to 96x, with 25mm, 2x barlow. Moon filter was indeed helpful at 96x. At 184x i preferred to observe without it.

Mare imbrium is indeed nice, with bunch of Craters: Copernicus, Eratosthenes, Archimedes and Plato.

Crater Copernicus western wall was striking bright, i guess because of sun light. Its really rough wall, or possibly multiple walls. Crater walls seemed pretty deep. At the center there are 2 prominent peaks, strikingly white in color.

Crater Eratosthenes is at the beginning of mountain range, Its features are like small scale Copernicus...except.. at the center of this crate, it has 3 peaks in triangular fashion.

Map says that the mountain range near Eratosthenes is of ~3000m elevation... but really didn't feel it.. I think if i would have observed couple of days before, i would have able to feel the height because of shadow. The mnt range at W and NW wall of Mare Imbirum seemed pretty tall. these mnt were in the dark, after the terminator, but their peaks were bright in the dark, must be because of their height.. I will watch them again tomorrow and will confirm it.

Crater Archimedes: Its a filled up crater, really smooth. nothing special with walls .. neigther have any central peak... but SW of it, there is some what rough area.. small scale mountain range.

Crate Plato at N of the Mare.. is indeed nice. Compared to other craters, size wise: Plato >> Copernicus > Archimedes > Eratosthenes. This is also a smooth, fllled up crater , no peaks. The W wall of this crater is impressive, the large rock sliding is visible.

As i mentioned in the beginning, I interpreted Mare Imbrium as Mare Serentatis.. so I opened a map of Serentatis.. and guess what... it has a really tiny crater called as "Sarabhai" .. It is named after Dr Vikram Sarabhai, ISRO founder. Felt really good. I should find out, if any other Indian celebrities are reached to the moon.

Crater Sarbhai is nothing special. Its really really tiny. only 7km wide, as compared to Copernicus being 93km It was really hard for me to catch it at 96x. At mag 184x, it was visible clearly, but no details..

TBD:
- Lunar regions named after Indian celebrities.


No comments: