Democritus (crater)

Democritus
Lunar Orbiter 4 image
Coordinates62°18′N 35°00′E / 62.3°N 35.0°E / 62.3; 35.0
Diameter37.78 km (23.48 mi)[1]
Depth2.0 km (1.2 mi)
Colongitude325° at sunrise
EponymDemocritus
Oblique view from Lunar Orbiter 4
Oblique view also from Lunar Orbiter 4

Democritus is a lunar impact crater that is located on the northern part of the Moon, just to the north of the Mare Frigoris.[2] T. W. Webb described it as "a deep ring-plain".[3] Just to the south of Democritus is the lava-flooded crater Gärtner,[4] which forms a bay on the mare. Directly to the north is Arnold,[2] another flooded formation.

The rim of Democritus is generally sharp-edged and shows little sign of erosion. It forms not quite a circle, with outward notch-like bulges that give it a slightly irregular shape. The inner walls have single or double terraces that lead down to a relatively flat interior floor. Near the midpoint of the crater is a small central peak.[2][5]: 13 

This crater is named after the Greek philosopher Democritus (c. 460 – c. 370 BC). Its designation was formally adopted by the International Astronomical Union in 1935.[1] Like many of the craters on the Moon's near side, it was given its name by Giovanni Riccioli, whose 1651 nomenclature system has become standardized.[6]: 212  Earlier lunar cartographers had given the feature different names: Michael van Langren's 1645 map calls it "Alfonsi IX Reg. Cast." after Alfonso IX of León and Castile,[6]: 198  and Johannes Hevelius called it "Mons Bontas".[6]: 202 

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 Democritus.[7]

Democritus[5]: 297  Latitude Longitude Diameter
A 61.6° N 32.4° E 11 km
B 60.1° N 28.6° E 12 km
D 62.9° N 31.2° E 8 km
K 63.1° N 40.7° E 7 km
L 63.4° N 39.7° E 18 km
M 63.6° N 37.1° E 5 km
N 63.6° N 34.3° E 16 km

The satellite features B includes a permanently shadowed region where the sunlight never reaches.[8]

References

  1. 1 2 "Democritus". Gazetteer of Planetary Nomenclature. USGS Astrogeology Research Program.
  2. 1 2 3 Moore, Patrick (2001). On the Moon. Sterling Publishing Co. p. 172. ISBN 978-0-304-35469-6.
  3. ↑ Webb, Rev. T. W. (1962). Celestial Objects for Common Telescopes (6th revised ed.). Dover. pp. 109, 154–159. Reprint: ISBN 978-0-486-20917-3
  4. ↑ Grego, Peter (2005). The Moon and How to Observe It. Astronomers' Observing Guides Series. London: Springer-Verlag. p. 135. ISBN 1-85233-748-6.
  5. 1 2 Bussey, B.; Spudis, P. (2004). The Clementine Atlas of the Moon. New York: Cambridge University Press. ISBN 978-0-521-81528-4.
  6. 1 2 3 Whitaker, Ewen A. (1999). Mapping and Naming the Moon. Cambridge University Press. ISBN 978-0-521-62248-6.
  7. ↑ Grego, P. (2015). "Satellite Crater". In Hargitai, H.; Kereszturi, Á. (eds.). Encyclopedia of Planetary Landforms. New York, NY: Springer. doi:10.1007/978-1-4614-3134-3_328.
  8. ↑ McGovern, J. Andrew; et al. (March 2013). "Mapping and characterization of non-polar permanent shadows on the lunar surface". Icarus. 223 (1): 566–581. Bibcode:2013Icar..223..566M. doi:10.1016/j.icarus.2012.10.018.

Sources

Wikimedia Commons logo
Wikimedia Commons has media related to Image:Lunar_crater_Democritus.png.
  • Price, Fred W. (1988). The Moon Observer's Handbook. Cambridge University Press. ISBN 978-0-521-33500-3.
  • Rükl, Antonín (1990). Atlas of the Moon. Kalmbach Books. ISBN 978-0-913135-17-4.
  • Wlasuk, Peter T. (2000). Observing the Moon. Springer. ISBN 978-1-85233-193-1.
This page is issued from Wikipedia. The text is available under Creative Commons Attribution-Share Alike 4.0 unless otherwise noted. Additional terms may apply for the media files.