Editing Mare Nectaris (section)

{{Infobox Lunar mare
|name        = Mare Nectaris
|image       = [[Image:Mare Nectaris.jpg|240px]]
|caption     = Mare Nectaris
|eponym      = Sea of Nectar
|coordinates = {{coord|15.2|S|34.6|E|globe:moon_type:landmark|display=inline,title}}
|diameter    = {{convert|340|km|mi|abbr=on}}<ref name=gazetteer/>
}}
[[File:Mare Nectaris Si ARP - Aldo Ferruggia.jpg|left|thumb|Selenochromatic rectified altered image of the Mare area; targeted some selenochromatic landmarks]]
[[File:Mare Nectaris AS08-18-2850.jpg|thumb|right|240px|View from [[Apollo 8]]]]

'''Mare Nectaris''' {{IPAc-en|'|n|ɛ|k|t|ə|r|ᵻ|s}} (Latin ''nectaris'', the "Sea of Nectar") is a small [[lunar mare]] or sea (a volcanic lava plain noticeably darker than the rest of the [[Moon]]'s surface) located south of [[Mare Tranquillitatis]] southwest of [[Mare Fecunditatis]], on the near side of the Moon. [[Montes Pyrenaeus]] borders the mare to the east and [[Sinus Asperitatis]] fuses to its northwestern edge. It is 84,000 square kilometers in size.<ref name=Whitford_Stark_1982/>

Several large craters are situated at the borders of Mare Nectaris. The biggest one is lava-filled [[Fracastorius (crater)|Fracastorius]] (124&nbsp;km), which fuses with the southern coast of the Sea. A prominent trio of 100-km craters [[Theophilus (crater)|Theophilus]], [[Cyrillus (crater)|Cyrillus]] and [[Catharina (crater)|Catharina]] is located near northwestern coast. Other notable feature is a "[[ghost crater]]" [[Daguerre (crater)|Daguerre]], almost entirely covered with lava, in the northern part of Mare Nectaris.<ref name=Grego_2006/>

Mare Nectaris is located in the central part of 860-km-diameter [[impact basin]], which was formed 3.8–3.9 billion years ago. This event marks the beginning of [[Nectarian]] period of the [[lunar geologic timescale]].<ref name=Tanaka_2012/><ref>[https://pubs.er.usgs.gov/publication/pp1348 The geologic history of the Moon].  [[USGS]] Professional Paper 1348. By [[Don Wilhelms|Don E. Wilhelms]], John F. McCauley, and Newell J. Trask.  U.S. Government Printing Office, Washington: 1987.  Table 9-3.</ref> The best-preserved part of the rim of this basin is called [[Rupes Altai]], in the southwest part of the basin.

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 (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 [[graben]]s on the western margin of the mare.<ref>{{cite web |
 title=Mare Nectaris | 
 work=lunar.arc.nasa.gov |  url=http://lunar.arc.nasa.gov/science/atlas/mare/mnectaris.htm |  archive-url=https://web.archive.org/web/20020616172845/http://lunar.arc.nasa.gov/science/atlas/mare/mnectaris.htm |  url-status=dead |  archive-date=June 16, 2002 |
 accessdate=October 16, 2007}}</ref>

A [[mass concentration (astronomy)|mass concentration]] (mascon), or gravitational high, was identified in the center of Mare Nectaris from Doppler tracking of the five [[Lunar Orbiter program|Lunar Orbiter]] spacecraft in 1968.<ref>{{cite journal | doi = 10.1126/science.161.3842.680 | title = Mascons: Lunar Mass Concentrations | year = 1968 |author1=P. M. Muller |author2=W. L. Sjogren | journal = Science | volume =  161 | issue = 3842  | pages = 680–684 | pmid=17801458| bibcode=1968Sci...161..680M | s2cid = 40110502 }}</ref>  The mascon was confirmed and mapped at higher resolution with later orbiters such as [[Lunar Prospector]] and [[Gravity Recovery and Interior Laboratory|GRAIL]].

<gallery heights="200px" mode="packed">
File:Mare Nectaris (LRO).png|Basin of Mare Nectaris ([[Lunar Reconnaissance Orbiter|LRO]] image mosaic). [[Rupes Altai]] is a thin bright streak in the lower left
File:Mare Nectaris (GLD100).jpg|Topographic map of the same area ([[Lunar Reconnaissance Orbiter|LRO]] data)
File:Nectaris basin GRAIL gravity.jpg|Gravity map based on [[Gravity Recovery and Interior Laboratory|GRAIL]]
File:Mare Nectaris AS11-42-6241.jpg|Oblique view facing southeast, from [[Apollo 11]].  The large crater right of center is [[Theophilus (crater)|Theophilus]], and [[Mädler (lunar crater)|Mädler]] is to its left.  [[Fracastorius (crater)|Fracastorius]] is near the central horizon, and the white mountain on the horizon at right is part of the Rupes Altai.  The teardrop-shaped crater in the lower left is [[Torricelli (crater)|Torricelli]].
</gallery>