The week of April 13-19 takes us from Day 26 to Day 2. This week we will highlight the moon crater Endymion, visible on Sunday night close to the terminator.
Endymion: [NE/D15; L=57°E] This is an older moon crater which somewhat resembles Plato [Day 8; NW/D9] in that it has a smooth, dark-chocolate floor and three-mile-high walls, which cast lovely shadow spires on the flood plain below when the Sun is low.
It is a large, 122–126 km wide, dark-floored impact crater located on the Moon’s northeastern limb (53.7°N, 56.5°E), near Mare Humboldtianum. Formed over 3.9 billion years ago, this Nectarian-period moon crater is known for its smooth, lava-flooded, low-albedo interior that contrasts with bright, rugged surrounding highlands, making it a prominent target for observers, especially in a small telescope.
OF ADDITIONAL INTEREST IN SPACE
On Wednesday, Mars is 4° south of the Moon, and on Sunday, it is 1° north of Saturn.
======================
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
- Moon Crater Schickard has Stripes - May 11, 2026
- Examples of Subsidence on the Moon: Moon Craters Posidonius and le Monnier - May 4, 2026
- Endymion – Moon Crater - April 27, 2026