Study: Asteroids show signs of aging

September 6, 2006

U.S. space scientists say they've determined asteroids show varying signs of aging -- a vital clue to the origin of meteorites.

Takahiro Hiroi and colleagues at Brown University discovered an asteroid has patchy surfaces in different stages of aging. Since meteorites come from asteroids, the finding suggests the aging process may be the reason why most meteorites look different from most asteroids.

The discrepancy between meteorites found on Earth and the composition of asteroids, as judged from their surface appearance, has been interpreted as a possible indication asteroid surfaces become altered over time -- a process called space weathering. It is thought that process makes asteroids gradually darker and redder.

The team was able to test that idea thanks to the close observation of the 1,800-foot-wide asteroid 25143 Itokawa by the Japanese Hayabusa spacecraft at the end of last year.

The researchers attribute the differences in appearance to varying amounts of very small particles of iron that are changed by space weathering since the meteorites were chipped off the asteroids long ago.

The research is described in the journal Nature.

Copyright 2006 by United Press International

Explore further: International study identifies the process of rock formation by meteor strikes or nuclear blasts

Related Stories

Recommended for you

Asteroid 2002 AJ129 to fly safely past Earth February 4

January 22, 2018

Asteroid 2002 AJ129 will make a close approach to Earth on Feb. 4, 2018 at 1:30 p.m. PST (4:30 p.m. EST / 21:30 UTC). At the time of closest approach, the asteroid will be no closer than 10 times the distance between Earth ...

A new bound on axions

January 22, 2018

An axion is a hypothetical elementary particle whose existence was postulated in order to explain why certain subatomic reactions appear to violate basic symmetry constraints, in particular symmetry in time. The 1980 Nobel ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.