Lunar topography from Apollo 15 and 16 laser altimetryIn the orbital plane of Apollo 15 the mean lunar radius is 1737.3 km, the mean altitude of terrae above maria is about 3 km, and the center-of-figure is displaced from the center-of-mass by about 2 km away from longitude 25 E. The Apollo 16 laser altimeter obtained a total of about 7.5 revolutions of partially overlapping data. The principal difference in results from Apollo 16 is the absence of any great far-side basin similar to the 1400-km wide feature found by Apollo 15, 1200 km to the south. This absence of a far-side depression in the Apollo 16 orbital plane largely accounts for a greater mean radius: 1738.1 km; a greater mean altitude of terrae above maria: about 4 km; and a greater offset of centers: about 3 km, also away from 25 E. In the Apollo 16, as well as Apollo 15, data the far-side terrae are much 'rougher' than the near-side terrae. Mare surfaces are generally smooth to within plus or minus 150 m, and have slopes of 1:500 to 1:2000 persisting over distances as great as 500 km.
Document ID
19740040250
Acquisition Source
Legacy CDMS
Document Type
Conference Proceedings
Authors
Kaula, W. M.
Schubert, G.
Lingenfelter, R. E. (California, University Los Angeles, Calif., United States)
Sjogren, W. L. (California Institute of Technology, Jet Propulsion Laboratory, Pasadena Calif., United States)
Wollenhaupt, W. R. (NASA Johnson Space Center Houston, Tex., United States)