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Mead (crater)
Encyclopedia
Mead is an impact crater
on Venus
named in honor of the cultural anthropologist Margaret Mead
.
Mead crater is the largest impact crater on Venus, with a diameter of 280 kilometres (174 mi). The crater has an inner and an outer ring and a small ejecta blanket surrounding the outer ring. The crater floor looks very similar in morphology to the surrounding plain.
Mead is classified as a multi-ring crater with its innermost, concentric scarp being interpreted as the rim of the original crater cavity. No inner peak-ring of mountain massifs is observed on Mead. The presence of hummocky, radar-bright crater ejecta crossing the radar-dark floor terrace and adjacent outer rim scarp suggests that the floor terrace is probably a giant rotated block that is concentric to, but lies outside of, the original crater cavity. The flat, somewhat brighter inner floor of Mead is interpreted to result from considerable infilling of the original crater cavity by impact melt and/or by volcanic lavas. To the southeast of the crater rim, emplacement of hummocky ejecta appears to have been impeded by the topography of preexisting ridges, thus suggesting a very low ground-hugging mode of deposition for this material.
Impact crater
In the broadest sense, the term impact crater can be applied to any depression, natural or manmade, resulting from the high velocity impact of a projectile with a larger body...
on Venus
Venus
Venus is the second planet from the Sun, orbiting it every 224.7 Earth days. The planet is named after Venus, the Roman goddess of love and beauty. After the Moon, it is the brightest natural object in the night sky, reaching an apparent magnitude of −4.6, bright enough to cast shadows...
named in honor of the cultural anthropologist Margaret Mead
Margaret Mead
Margaret Mead was an American cultural anthropologist, who was frequently a featured writer and speaker in the mass media throughout the 1960s and 1970s....
.
Mead crater is the largest impact crater on Venus, with a diameter of 280 kilometres (174 mi). The crater has an inner and an outer ring and a small ejecta blanket surrounding the outer ring. The crater floor looks very similar in morphology to the surrounding plain.
Mead is classified as a multi-ring crater with its innermost, concentric scarp being interpreted as the rim of the original crater cavity. No inner peak-ring of mountain massifs is observed on Mead. The presence of hummocky, radar-bright crater ejecta crossing the radar-dark floor terrace and adjacent outer rim scarp suggests that the floor terrace is probably a giant rotated block that is concentric to, but lies outside of, the original crater cavity. The flat, somewhat brighter inner floor of Mead is interpreted to result from considerable infilling of the original crater cavity by impact melt and/or by volcanic lavas. To the southeast of the crater rim, emplacement of hummocky ejecta appears to have been impeded by the topography of preexisting ridges, thus suggesting a very low ground-hugging mode of deposition for this material.