Elliptical structure of the lunar South Pole-Aitken basin
نویسندگان
چکیده
The South Pole-Aitken basin (SP-A) is the largest and oldest basin on the Moon. The basin has usually been interpreted to exhibit a degraded circular structure, but here we demonstrate that the topography, iron and thorium signatures of the basin are well described by ellipses with axes measuring 2400 by 2050 km and centered at 53 , 191 E. Topography, abundances of iron, thorium, and the distribution of mare basalts are all elevated in the northern halves of the ellipses. We also identify an outer topographic ellipse whose semiminor axis scales with the main topographic ellipse by approximately ffiffiffi
منابع مشابه
Volumes of lunar lava ponds in South Pole-Aitken and Orientale Basins: Implications for eruption conditions, transport mechanisms, and magma source regions
In an effort to characterize individual eruptive phases and events, 86 isolated mare deposits (ponds) in the lunar South Pole-Aitken and Orientale regions were analyzed to obtain information on areas, volumes, and other characteristics. Deposits likely to represent single eruptive episodes have area mean values of-2000 km 2 in the South Pole-Aitken Basin and -1100 km 2 in the Orientale Basin. P...
متن کاملConnecting Lunar Meteorite Dhofar 961 to the South Pole Aitken Basin through Lunar Prospector Gamma-ray Data
Introduction: Lunar meteorite Dhofar 961, a complex, lithic-clast-rich impact breccia [1,2], was called out by [3-6] as a candidate for an origin in the South Pole – Aitken (SPA) Basin region of the Moon (the SPA Terrane) on the basis of its relatively mafic, but nonmare lithologic and major-element chemical composition. It also has an incompatible-element signature that differs from the KREEP-...
متن کاملTopography of the Lunar South Polar Region Implications for the Size and Location of Permanently Shaded Areas
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...
متن کاملSurviving the heavy bombardment: Ancient material at the surface of South Pole-Aitken Basin
[1] The oldest, deepest, and largest basin recognized on the lunar surface is the South Pole-Aitken (SPA) basin. In the time since its formation, several processes have modified the original interior of the basin, including the introduction of foreign material by impact basins during the period of heavy bombardment. These later basins redistributed material ballistically across the lunar surfac...
متن کامل