单词	mascon
释义	mascon noun mas·​con ˈma-ˌskän  : any of the high-density regions below the surface of lunar maria that are held to perturb the motion of spacecraft in lunar orbit Example Sentences Recent Examples on the Web Other large craters have what are known as mascons, short for mass concentrations. National Geographic, 11 June 2019 Discovered in 1968 by scientists at NASA's Jet Propulsion Laboratory, mascons show up in gravity maps as bullseyes—a central circle of strong gravity surrounded by a ring of weak gravity and then another ring of stronger gravity. National Geographic, 11 June 2019 Plus, the moon’s lopsided topography – riddled with mascons, or areas of dense material with higher-than-average gravitational pull – makes satellites’ orbits incredibly unpredictable. The Washington Post, The Denver Post, 14 Mar. 2017 The lunar crust formed around those craters, leaving mass concentrations (mascons) of gravity behind in some areas. Erin Blakemore, Smithsonian, 14 Mar. 2017 Plus, the moon’s lopsided topography — riddled with mascons, or areas of dense material with higher-than-average gravitational pull — makes satellites’ orbits incredibly unpredictable. The Washington Post, The Mercury News, 13 Mar. 2017 Word History Etymology mas(s) entry 2 + con(centration) First Known Use 1968, in the meaning defined above
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