Article,
Martian meteorite launch: High-speed ejecta from small craters
Science, 298 (5599): 1752--1756 (2002)
Abstract
We performed high-resolution computer simulations of impacts into
homogeneous and layered martian terrain analogs to try to account
for the ages and characteristics of the martian meteorite collection
found on Earth. We found that craters as small as similar to3 kilometers
can eject similar to10(7) decimeter-sized fragments from Mars, which
is enough to expect those fragments to appear in the terrestrial
collection. This minimum crater diameter is at least four times smaller
than previous estimates and depends on the physical composition of
the target material. Terrain covered by a weak layer such as an impact-generated
regolith requires larger, therefore rarer, impacts to eject meteorites.
Because older terrain is more likely to be mantled with such material,
we estimate that the martian meteorites will be biased toward younger
ages, which is consistent with the meteorite collection.
