Neugrund crater

Boulder of gneiss breccia on Osmussaar, Estonia, apparently thrown there by the Neugrund impact.

Neugrund is a meteorite crater in Estonia. It is 8 km (5.0 mi) in diameter and is estimated to have been formed 470 million years ago in the Ordovician period. The crater is at the bottom of the sea and is not exposed at the surface. Boulders of gneissic breccia found on the coast of Osmussaar, a nearby island, are believed to have been thrown there by the explosion.[1] It has been proposed that the Neugrund crater was created during the Ordovician meteor event when a hypothetical large asteroid transferred directly into a resonant orbit with Jupiter, which shifted its orbit to intercept Earth.[2][3][4]

References

  1. ↑ "Neugrund". Earth Impact Database. University of New Brunswick. Retrieved 2009-08-19.
  2. ↑ Heck, Philipp; Birger Schmitz, Heinrich Baur, Alex N. Halliday. Rainer Wieler (15 July 2004). "Fast delivery of meteorites to Earth after a major asteroid collision". Nature 430 (6997): 323–325. Bibcode:2004Natur.430..323H. doi:10.1038/nature02736. PMID 15254530. Cite uses deprecated parameter |coauthors= (help)
  3. ↑ H. Haack et al. Meteorite, asteroidal, and theoretical constraints on the 500-Ma disruption of the L chondrite parent body, Icarus, Vol. 119, p. 182 (1996).
  4. ↑ Korochantseva et al. "L-chondrite asteroid breakup tied to Ordovician meteorite shower by multiple isochron 40Ar-39Ar dating" Meteoritics & Planetary Science 42, 1, pp. 3-150, Jan. 2007.

Coordinates: 59°20′N 23°40′E / 59.333°N 23.667°E / 59.333; 23.667


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