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Астронет: Астрономическая картинка дня Ударный кратер Мёлнир http://www.variable-stars.ru/db/msg/1163090/eng |
Credit & Copyright: F. Tsikalas,
S.T. Gudlaugsson, J.I. Faleide, O. Eldholm
(Geology Dept., Univ. Oslo)
Explanation:
The stark surface of
Earth's moon is pocked with large craters,
records of a history of fierce bombardment by the solar system's
formative debris.
It may be difficult to imagine, but nearby
planet Earth itself has endured a
similar cosmic pounding, though
oceans, weathering, and geological activity
have removed or hidden many of the telltale scars.
For example, this false color image produced from seismic data shows
a recently discovered ringed structure
about 24 miles wide
on the floor of the Barents Sea.
It is most probably the result of the impact,
roughly 150 million years ago,
of a mile or so wide asteroid-like body.
Estimates indicate that
the energy released in the
impact could have
been as high as a million megatons of TNT,
resulting in immense earthquakes and tidal waves.
Drawing on Norse mythology, the crater has been
aptly named
Mjølnir - Thor's hammer.
Authors & editors:
Robert Nemiroff
(MTU) &
Jerry Bonnell
(USRA)
NASA Web Site Statements, Warnings,
and Disclaimers
NASA Official: Jay Norris.
Specific
rights apply.
A service of:
LHEA at
NASA /
GSFC
& Michigan Tech. U.