|
Approximately 2,000 near-Earth objects
(NEOs) larger than one km diameter revolve around
the sun on short-period orbits that can occasionally
intersect the orbit of the Earth. Only about 7%
of this estimated population has been discovered.
There is about one chance in a thousand that one
of these undiscovered objects is destined to collide
with Earth during the lifespan of the average
American. Such a collision has the potential of
injecting sufficient dark material into the atmosphere
to cause...
Impacts by Earth-approaching asteroids
and comets pose a significant hazard to life and
property. Although the annual probability of the
Earth being struck by a large asteroid or comet
is extremely small, the consequences of such a
collision are so catastrophic that it is prudent
to assess the nature of the threat and prepare
to deal with it. The first step in any program
for the prevention or mitigation of impact catastrophes
must involve...
|
