二十世纪最令人惊奇的成就之一是从一颗人造卫星上的实验所收集的资料中提供了一些最引人注目的地球行星的影像。这颗卫星是美国宇航局(NASA)在1978年夏天发射的海洋卫星。虽然,它在太空仅逗留了三个月,但是,它所收集的关于地球形状的资料却比以前三个世纪还要多。许多研究所的地球物理学家已经分析和解释了大量离地面800公里的高空所采集的雷达测高计资料。卫星上装载的雷达测高计如此精密,以至卫星飞行高度可以用大约 One of the most amazing achievements of the twentieth century was the availability of some of the most dramatic images of Earth’s planet from the data collected from experiments on a satellite. The satellite is a marine satellite launched by NASA in the summer of 1978. Although it lasted only three months in space, it collected more information about the shape of the Earth than it had in the past three centuries. Many geophysicists at the Institute have analyzed and interpreted radar altimetry data collected at high altitudes over a distance of 800 kilometers from the ground. The radar altimeter mounted on the satellite is so precise that satellite flight altitudes can be approximated