people to the hospital with
lacerations from the flying
glass.
Originally, astronomers
thought that the Chelyabinsk
meteor came from a 1.24mile-wide (2 kilometers)
near-Earth asteroid called
1999 NC43. But a closer look
at the asteroid's orbit and
likely mineral composition,
gained from spectroscopy,
suggests few similarities
between it and the Russian
meteor
"These two bodies shared
similar orbits around the sun,
and initial studies suggested
even similar compositions,"
lead study author Vishnu
Reddy, a scientist with the
nonprofit Planetary Science
Institute in Tucson, Arizona,
said in a statement.
However, "the composition
of [the] Chelyabinsk
meteorite that was recovered
after the event is similar to a
common type of meteorite
called LL chondrites," he
added. "The near-Earth
asteroid has a composition
that is distinctly different
from this."
More generally, Reddy and
his colleagues' work showed
that it is difficult to make
predictions about what
particular asteroid could have
shed pieces that slammed into
Earth. Because most asteroids
are so small and their orbits
are "chaotic," it's hard to
make a firm link, the authors
said.
A paper based on the
research appears in the
journal Icarus.