1999 JM8: A Rock Too Close
Explanation:
Nearly four kilometers across,
the huge rock known as
1999 JM8 silently passed only 8.5 million kilometers
from the Earth in early August.
The small
asteroid was completely unknown before May.
Every few centuries, a rock like this impacts the Earth,
with the potential to disrupt modern civilization.
Radar from two of the largest
radio telescopes,
Arecibo and
Goldstone, tracked
and imaged the
Apollo asteroid as it approached
to only 22 times the distance to the Moon.
Although
1999 JM8 missed the Earth, thousands of similar but
unknown asteroids
likely exist that cross Earth's orbit.
In fact, four asteroids have
passed inside the orbit of the Moon within the last decade.
Possibly of larger
concern to humanity are the more
numerous rocks near 100 meters across. Were one of
these to strike an ocean, a dangerous
tidal wave might occur.
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.
