Billy is a
lunarimpact crater that is located at the southern fringes of the
Oceanus Procellarum, in the western hemisphere of the
Moon. It was named after French mathematician
Jacques de Billy.[1] It lies to the southeast of the similar-sized crater
Hansteen, and west-southwest of the flooded
Letronne.
The interior floor of Billy has been flooded by
basalticlava, leaving a dark surface due to the low
albedo. The portion of the rim remaining above the surface is narrow and low, with a thin inner wall. Only a few tiny craterlets mark the interior.
To the north of the crater is a triangular mountainous formation named
Mons Hansteen, from the nearby crater. Southeast of Billy is a
rille, designated Rima Billy, that runs 70 kilometers to the south.
Satellite craters
By convention these features are identified on lunar maps by placing the letter on the side of the crater midpoint that is closest to Billy.
Billy
Latitude
Longitude
Diameter
A
14.3° S
46.3° W
7 km
B
12.2° S
47.6° W
25 km
C
16.1° S
49.0° W
6 km
D
14.9° S
48.3° W
11 km
E
15.0° S
49.6° W
2 km
H
15.6° S
49.6° W
3 km
K
12.9° S
48.7° W
4 km
References
^"Billy (crater)". Gazetteer of Planetary Nomenclature. USGS Astrogeology Research Program.
Andersson, L. E.;
Whitaker, E. A. (1982). NASA Catalogue of Lunar Nomenclature. NASA RP-1097.
Menzel, D. H.; Minnaert, M.; Levin, B.; Dollfus, A.; Bell, B. (1971). "Report on Lunar Nomenclature by the Working Group of Commission 17 of the IAU". Space Science Reviews. 12 (2): 136–186.
Bibcode:
1971SSRv...12..136M.
doi:
10.1007/BF00171763.
S2CID122125855.