Mare Nectaris

From Wikipedia, the free encyclopedia
Jump to: navigation, search
Mare Nectaris
Mnectaris.jpg
Mare Nectaris
Coordinates 15°12′S 34°36′E / 15.2°S 34.6°E / -15.2; 34.6Coordinates: 15°12′S 34°36′E / 15.2°S 34.6°E / -15.2; 34.6
Diameter 340 km (210 mi)[1]
Eponym Sea of Nectar
Basin of Mare Nectaris (LRO image mosaic). Rupes Altai is a thin bright streak in the lower left
Topographic map of the same area (LRO data)

The Sea of Nectar (Mare Nectaris) is a small lunar mare or sea (a volcanic lava plain noticeably darker than the rest of the Moon's surface) located near the Sea of Tranquility (Mare Tranquillatis) and the Sea of Fecundity (Mare Fecunditatis). Montes Pyrenaeus borders the mare to the east and Sinus Asperitatis fuses to it's northwestern edge, connecting it with the Sea of Fecundity. It is 84,000 square kilometers in size.[2]

Several large craters are situated at the borders of Mare Nectaris. Biggest one is lava-filled Fracastorius (124 km), which fuses with southern coast of the Sea. A prominent trio of 100-km craters Theophilus, Cyrillus and Catharina is located near northwestern coast. Other notable feature is a "ghost crater" Daguerre, almost entirely covered with lava, in the northern part of Mare Nectaris.[3]

Mare Nectaris is located in the central part of 860-km-diameter impact basin, which was formed 3.8–3.9 billions year ago. This event marks the beginning of Nectarian period of the lunar geologic timescale.[4] Best-preserved (southwestern) part of the rim of this basin is called Rupes Altai.

Lava filling of Mare Nectaris is younger than the basin itself. The mare material is approximately 1000m in depth, and mainly of the Nectarian period and the Lower Imbrian epoch, with the mare material of the Upper Imbrian epoch. The crater Theophilus on the northeastern side of the mare is of the Eratosthenian period. Thus, the crater is younger than the mare to its southeast. Enough subsidence has occurred to open a few arcuate grabens on the western margin of the mare.[5]

Lunar nearside with major maria and craters labelled.

References[edit]

  1. ^ "Mare Nectaris". Gazetteer of Planetary Nomenclature. International Astronomical Union (IAU) Working Group for Planetary System Nomenclature (WGPSN). 2010-10-18. Retrieved 2014-12-11. 
  2. ^ Whitford-Stark J. L. (May 1982). "A preliminary analysis of lunar extra-mare basalts: Distribution, compositions, ages, volumes, and eruption styles". The Moon and the Planets 23 (3): 323–338. Bibcode:1982M&P....26..323W. doi:10.1007/BF00928015. 
  3. ^ Grego P. (2006). The Moon and How to Observe It. Springer Science & Business Media. pp. 27, 205, 220. ISBN 978-1-846-28243-0. 
  4. ^ Tanaka K.L., Hartmann W.K. (2012). "Chapter 15 – The Planetary Time Scale". In F. M. Gradstein, J. G. Ogg, M. D. Schmitz, G. M. Ogg. The Geologic Time Scale. Elsevier Science Limited. pp. 275–298. doi:10.1016/B978-0-444-59425-9.00015-9. ISBN 978-0-444-59425-9. 
  5. ^ "Mare Nectaris". lunar.arc.nasa.gov. Retrieved October 16, 2007.