South Pole-Aitken basin. Mosaic image of the Constellation region of the South Pole-Aitkin (SPA) basin, the largest and oldest crater on the Moon. The

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South Pole-Aitken basin. Mosaic image of the Constellation region of the South Pole-Aitkin (SPA) basin, the largest and oldest crater on the Moon. The SPA basin, on the far side of the Moon, measures approximately 2,500 kilometres in diameter, which is nearly one quarter of the Moon's circumference. The Constellation region is of interest because it is in a deep area of the basin where some original material from the impact may still be found. Melting caused by the impact would have changed the composition of materials, allowing the date of the impact to be determined. Imaged by the NASA's LROC (Lunar Reconnaissance Orbiter Camera) wide angle camera (WAC).

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Size: 3820px × 6304px
Photo credit: © NASA/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: angle, astronomical, astronomy, basin, biggest, black--white, camera, constellation, crater, cratered, craters, impact, largest, lroc, lunar, monochrome, moon, mosaic, oldest, orbiter, pole-aitken, reconnaissance, region, solar, south, space, surface, system, wac, wide