Topography of the lunar south polar region: Implications for the size and location of permanently shaded areas
Abstract
We analyze Clementine altimetry to constrain the size and location of proposed permanently shadowed regions in the vicinity of the lunar south pole. Long and short wavelength topography in the vicinity of the pole, in combination with measurements of depths of well-preserved craters and basins and the lunar topographic power spectrum, have direct bearing on the nature of elevations in the south polar region. A criterion based on geometric considerations and altimetry demonstrates that the existence of permanent shadowing is not very sensitive to the elevation of the south pole. In addition, permanent shadowing cannot be a consequence of large structures such as the South Pole-Aitken Basin and/or a 300-km degraded polar basin. Perennially dark regions, if they exist, are most likely associated with craters or other axisymmetric features with diameters of at most 80 km centered at the pole. For structures displaced 2° from the pole the maximum allowable diameter decreases to ∼30 km.
- Publication:
-
Geophysical Research Letters
- Pub Date:
- September 1997
- DOI:
- 10.1029/97GL02111
- Bibcode:
- 1997GeoRL..24.2183Z
- Keywords:
-
- Clementine Spacecraft;
- Polar Regions;
- Position (Location);
- Moon;
- Lunar Surface;
- Backscattering;
- Electromagnetic Scattering;
- Planetology: Solid Surface Planets: Surface materials and properties;
- Planetology: Solid Surface Planets: Erosion and weathering;
- Planetology: Solid Surface Planets: Origin and evolution