Secondary craters on Europa and implications for cratered surfaces
Article Abstract:
A comparatively sparse crater population on Jupiter's icy moon Europa is analyzed. The findings show that secondary craters comprise about 95% of the small craters on Europa and hence it can be concluded that large primary impacts into a solid surface produce far more secondaries than previously believed, implying that the small crater populations on the Moon, Mars and other large bodies must be dominated by secondaries.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 2005
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Magnetic impact craters
Article Abstract:
The hypothesis of demagnetized impact basins and all that it implies about Mars evolution is discussed. Though they measure unusually strong magnetizations of bedrock samples in the giant Vredefort impact crater of South Africa, aerial measurements of magnetic fields over the crater are lower than over surrounding areas.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 2005
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A more ancient shield
Article Abstract:
Studies are conducted to explore the start-up date of Earth's magnetic field that has protected atmosphere from erosion by the solar wind. Thermodynamic model calculations give a most likely starting date of 3.5 billion years ago for inner-core solidification.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 2007
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