The week of October 13-19 takes us from Lunar Day 22 to Day 28. This week we will highlight the basin Grimaldi, visible on Tuesday night.
Grimaldi: [SW/K3; L=68°W] In comparison to Aristarchus (Day 11), which is the brightest spot on the Moon, Grimaldi is the darkest. Sunrise over Grimaldi is quite a lovely sight. The rim around Grimaldi has been heavily eroded by subsequent impacts, but once the floor is illuminated you will see quite a number of small craters, mounds, spots, streaks, and wrinkle ridges. LTP’s have also been spotted in the region, and some observers have reported being able to see a St. Andrew’s Cross emblazoned on the west wall. Grimaldi, in spite of its diameter of 143 miles, is a genuine basin, and if you look closely you might be able to trace out vestiges of an external ring.
OF ADDITIONAL INTEREST IN SPACE
Full Moon is on Thursday.
On Saturday, the Pleiades is 0.1° south of the Moon.
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It is highly recommended that you get a copy of Sky and Telescope’s Field Map of the Moon, the very finest Moon map available for use at the telescope. It is available for $10.95 at www.skyandtelescope.com and on Amazon. All features mentioned in this blog will be keyed to the grid on the Field Map and will look like this: Plato: [NW/D9]
Credits:
Courtesy of Gray Photography of Corpus Christi, Texas
Lunar photos: NASA / USGS / BMDO / LROC / ASU / DLR / LOLA / Moon Globe. Used by permission
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