Gassendi (crater)

Gassendi (crater)
Oblique view of Gassendi from Apollo 16. NASA photo.
Diameter	110 km
Depth	1.9 km
Colongitude	40° at sunrise
Eponym	Pierre Gassendi

Gassendi is a large lunar crater feature located at the northern edge of Mare Humorum. The formation has been inundated by lava during the formation of the mare, so only the rim and the multiple central peaks remain above the surface. The outer rim is worn and eroded, although it retains a generally circular form. A smaller crater Gassendi A intrudes into the northern rim, and joins a rough uplift at the northwest part of the floor. The crater pair bears a curious resemblance to a diamond ring.

In the southern part of the crater floor is a semi-circular ridge-like formation that is concentric with the outer rim. It is in the southern part where the rim dips down to its lowest portion, and a gap appears at the most southern point. The rim varies in height from as little as 200 meters to as high as 2.5 kilometers above the surface. The floor has numerous hummocks and rough spots. There is also a system of rilles that criss-cross the floor, named the Rimae Gassendi.

On some older maps the crater Gassendi A was called Clarkson, after the British amateur astronomer and selenographer Roland L T Clarkson, but this name is not officially recognized by the IAU and the name has been removed.

Satellite craters

By convention these features are identified on lunar maps by placing the letter on the side of the crater mid-point that is closest to Gassendi.

Gassendi	Latitude	Longitude	Diameter
A	15.5° S	39.7° W	33 km
B	14.7° S	40.6° W	26 km
E	18.4° S	43.5° W	8 km
F	15.0° S	45.0° W	8 km
G	16.8° S	44.6° W	8 km
J	21.6° S	37.0° W	9 km
K	18.7° S	43.6° W	6 km
L	20.4° S	41.8° W	6 km
M	18.6° S	39.0° W	3 km
N	18.0° S	39.2° W	3 km
O	21.9° S	35.1° W	11 km
P	17.2° S	40.6° W	2 km
R	21.9° S	37.7° W	3 km
T	19.0° S	35.4° W	10 km
W	17.6° S	43.7° W	6 km
Y	20.8° S	38.3° W	5 km

References

Andersson, L. E.; Whitaker, E. A., (1982). NASA Catalogue of Lunar Nomenclature. NASA RP-1097.
Blue, Jennifer (July 25, 2007). "Gazetteer of Planetary Nomenclature". USGS. http://planetarynames.wr.usgs.gov/. Retrieved 2007-08-05.
Bussey, B.; Spudis, P. (2004). The Clementine Atlas of the Moon. New York: Cambridge University Press. ISBN 0-521-81528-2.
Cocks, Elijah E.; Cocks, Josiah C. (1995). Who's Who on the Moon: A Biographical Dictionary of Lunar Nomenclature. Tudor Publishers. ISBN 0-936389-27-3.
McDowell, Jonathan (July 15, 2007). "Lunar Nomenclature". Jonathan's Space Report. http://host.planet4589.org/astro/lunar/. Retrieved 2007-10-24.
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. edit
Moore, Patrick (2001). On the Moon. Sterling Publishing Co. ISBN 0-304-35469-4.
Price, Fred W. (1988). The Moon Observer's Handbook. Cambridge University Press. ISBN 0-521-33500-0.
Rükl, Antonín (1990). Atlas of the Moon. Kalmbach Books. ISBN 0-913135-17-8.
Webb, Rev. T. W. (1962). Celestial Objects for Common Telescopes (6th revision ed.). Dover. ISBN 0-486-20917-2.
Whitaker, Ewen A. (1999). Mapping and Naming the Moon. Cambridge University Press. ISBN 0-521-62248-4.
Wlasuk, Peter T. (2000). Observing the Moon. Springer. ISBN 1-85233-193-3.

External links

Wood, Chuck (2006-07-12). "Inside Gassendi". Lunar Photo of the Day. http://www.lpod.org/?m=20060712. Retrieved 2006-07-12.
Wood, Chuck (December 22, 2007). "Unnecessary Mystery". Lunar Photo of the Day. http://www.lpod.org/?m=20071222. Retrieved 2008-01-02.
Trimley's Moon Man - Roland Clarkson (accessed 9/16/05)