国外媒体:美科学家称月球正在缩小(在线收听) |
Moon is shrinking, say astronomers The Man in the Moon has become the latest victim of contraction in the housing market. Astronomers reporting on Thursday in the US journal Science said they had found previous undetected landforms which indicate that Earth's satellite has been shrinking... albeit by only a tiny amount. The intriguing features, called lobate scarps, arefaultscreated when the Moon's once-molten interior began to cool, causing the lunar surface to contract and then crinkle, they said. Relative to the Moon's age, estimated at around 4.5 billion years, the contraction is recent, occurring less than a billion years ago, and is measured at about 100 meters (325 feet). Lobate scarps were first spotted near the lunar equator in the 1970s bypanoramiccameras aboard the Apollo 15, 16 and 17 missions. Fourteen new faults have been been spotted inhigh-resolutionimages taken by NASA's Lunar Reconnaissance Orbiter. The new discoveries show that the scarps are globally distributed and not clustered in equatorial regions, and this provides powerful evidence for the contraction scenario. The investigation was headed by Thomas Watters of the Center for Earth and Planetary Studies at the Smithsonian Museum's National Air and Space Museum, Washington. “月球人”成为月球“房地产市场”紧缩的最新受害者。 天文学家于上周四在美国《科学》杂志发表的报告中称,他们发现了月球上出现了一些之前未被勘测到的地貌,这些地貌表明地球的这颗卫星正在缩小——尽管幅度很小。 这些被称为“叶状陡坡”的有趣的地貌特征是在月球一度熔化的内核开始冷却的过程中形成的断层,这一过程使得月球表面发生收缩,并出现褶皱。 这一收缩过程是在“近期”发生的,相对于月球45亿年的高龄,这个“近期”指的是不到10亿年前。但据测算这一收缩的幅度仅为约100米(325英尺)。 “叶状陡坡”于上世纪70年代在月球赤道附近首次被发现,是阿波罗15号、16号、17号飞船上的全景照相机拍到的。 之后又有14处新的断层被发现,美国宇航局的月球勘测轨道飞行器拍摄了这些断层的高清照片。 这些新发现表明,叶状陡坡分布在月球各地,并非只是集中在月球的赤道地区,这也为月球正在缩小这一假设提供了有力证据。 这项研究由华盛顿史密森国家航空航天博物馆地球与行星研究中心的托马斯沃特斯负责开展。 |
原文地址:http://www.tingroom.com/lesson/gwmtxw/513302.html |