Downs G S, Goldstein R M, Green R R, Morris G A
Science. 1971 Dec 24;174(4016):1324-7. doi: 10.1126/science.174.4016.1324.
Radar observations of a narrow belt of the surface of Mars, centered at 16 degrees south latitude, show a very rugged terrain, with elevation differences greater than 13 kilometers from peak to valley. For nearby points, the relative altitude is measured to 40 meters at best; the precision is worse for points at different latitudes, or widely separated in longitude, because of orbital uncertainties. Some of the larger craters have been resolved, and their depth and, in some cases, the height of the raised rim have been measured. Where high resolution photographs, are available, the correlation is excellent.
对火星表面一条以南纬16度为中心的狭窄地带进行的雷达观测显示，该区域地形极为崎岖，从山峰到山谷的海拔落差超过13千米。对于附近的点，相对海拔测量精度最高可达40米；由于轨道不确定性，不同纬度或经度相距较远的点的测量精度更差。一些较大的陨石坑已被分辨出来，并且测量了它们的深度，在某些情况下还测量了凸起边缘的高度。在有高分辨率照片的地方，两者的相关性非常好。
