A small central rise in an eroded crater

Feature Profile & Selenographic Data

Feature type

crater

Coordinates

67.46° S · 147.95° W

Diameter

93.48 km

IAU approval

1970/01/01 00:00:00

LAC quadrangle

LAC-142 · Zeeman

Geological Period

Pre-Nectarian

Geological Chronicle

Crommelin lies near the Moon’s south pole, on the far side and within the South Pole-Aitken basin. Zeeman lies to its south, Numerov to the west-southwest and Lemaître to the north. The crater dates to the Pre-Nectarian period.

Subsequent impacts have almost completely degraded the formation, leaving little more than a crater-riddled depression. An equally worn crater lies across the northern rim, and Crommelin X is attached to the outward-bulging northwest perimeter.

The largest craterlets inside Crommelin form a pair near the southern rim. At the center is a slight peak, little more than a low rise. Its spectra fit an olivine-bearing gabbroic norite mineralogy, which was excavated from depths of 3.5 to 9.4 km.

Crommelin is named for British astronomer Andrew C. D. Crommelin, an expert on comets. The International Astronomical Union formally adopted the crater’s designation in 1970.

Chronology & Exploration

1. Pre-Nectarian Formation period

   Crommelin dates to the Pre-Nectarian period on the lunar geologic timescale.

2. Undated Central-peak spectra described

   The central-peak spectra fit an olivine-bearing gabbroic norite mineralogy, which was excavated from a depth of 3.5 to 9.4 km.

3. 1970 Designation adopted

   The International Astronomical Union formally adopted Crommelin’s designation.

Scientific Sources & References

• International Astronomical Union Gazetteer — Registry record for the crater’s identity, coordinates, diameter and name origin.
• Wikipedia: Crommelin (lunar crater) — Local source for the crater’s setting, geology, spectra and naming.

Name Origin

Andrew Claude De La Cherois; British astronomer (1865-1939).