December 18, 2017

Astro-Challenge: Scouting Out the Lunar Straight Wall.

The waxing gibbous Moon with the Mare Nubium/Rupes Recta region circled. (Photo by Author)

An interesting lunar feature comes into view this week, right around 1st Quarter phase. Located in the Mare Nubium just before the start of the Lunar Highlands sits a feature known as the Lunar Straight Wall. 120 kilometers long and about 400 meters high, this scarp is hard to miss as a long shadow slice along the surface of the Moon. Visible in even small telescopes at moderate magnification, the Lunar Straight Wall is generally visible within 24 hours of 1st Quarter, which occurs this week at 04:56 AM EDT/ 08:56 AM GMT. [Read more...]