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Friday the 13th Might Be Pretty
Frightening After All -- in 2029
By Linda Orlando, Buzzle.com
If scientists and astronomers
have it calculated correctly,
Friday, April 13, 2029, could be
a very unlucky day for Earth if
the asteroid Apophis continues
on its path toward Earth, as
Costa Rica, Nicaragua, and
Venezuela are all potential
targets for total destruction,
Apophis was the name of the
ancient Egyptian god of darkness
and destruction. So there is no
more appropriate moniker
astronomers could have chosen to
assign to a 25-million-ton,
820-ft. wide asteroid that is
expected to slice across the
orbit of the moon and hurtle
toward Earth at more than 28,000
miles per hour on Friday the
13th of April, 2029, at 4:36
a.m. Greenwich Mean Time.
Scientists are 99.7% certain
that Apophis, a huge pockmarked
rock that carries the energy of
65,000 Hiroshima bombs, will
pass the Earth at a distance of
only 18,800 to 20,800 miles.
That distance is shorter than a
round-trip flight from
Melbourne, Australia, to New
York City, and well inside the
orbits of many of the
geosynchronous communications
satellites that are now circling
the Earth. Just after dusk on
April 13, people in Europe,
Africa, and parts of Asia will
be able to see what looks like a
star slowly making its way
westward through the sky.
Apophis will be the first
asteroid in human history to be
clearly visible to the naked
eye.
The asteroid will be packing
enough power to wipe out a small
country or churn up an 800-ft.
high tsunami. Current
projections show the asteroid’s
impact occurring somewhere along
a 30-mile-wide path stretching
from Russia across the Pacific
Ocean into Central America and
then across the Atlantic.
Although San Jose, Costa Rica,
Nicaragua, and Venezuela are all
potential targets for total
destruction, scientists believe
the most likely target to be
several thousand miles off the
West Coast of the United States,
where the impact would create a
5-mile wide crater in the ocean
floor. The impact would trigger
tsunamis that could pound the
coast of California with 50-foot
waves.
Scientists believe that if
Apophis passes the Earth at a
distance of exactly 18,893
miles, it will go through a
"gravitational keyhole," where
the Earth’s gravity could pull
Apophis off track just enough to
cause it to enter an orbit that
is seven-sixths as long as the
Earth’s orbit. If that happens,
then exactly seven years later,
as Apophis comes back around,
the planet would be dead center
in the path of the behemoth.
Fortunately, current tracking
estimates put the odds of that
happening at about 45,000 to 1.
However, former astronaut Rusty
Schweickart, now 71, who served
on the Apollo 9 mission in 1969,
feels that even a tiny risk
cannot be ignored. Through his
B612 Foundation, which he
co-founded in 2001, Schweickart
has been urging NASA to start
now making preparations to do
something about the asteroid.
"We need to act," he said. "If
we blow this, it’ll be
criminal."
Despite Hollywood’s imaginative
cinematic escapades, current
technology does not provide any
way for Apophis to be deflected
by some 5000 miles to miss the
Earth in 2036, if it does go
through the gravitational
keyhole and comes back around
with our planet in its
crosshairs. Not even Bruce
Willis and his crew of
roughnecks would be able to do a
thing about it. Unless some
revolutionary new technology
emerges, there would be little
scientists could do other than
plotting the precise impact
point and begin evacuating
people.
In 2005, Schweickart began
urging NASA administrator
Michael Griffin to start
planning a mission to land a
radio transponder on Apophis, in
an effort to track the
asteroid’s path to confirm that
it will not hit the
gravitational keyhole. If that
data shows that the path will
bring it into the keyhole, there
would still be time to do
something about it and launch a
deflection mission. Using
current technology, we could
nudge it slightly off course by
hitting it with a simple 1-ton
"kinetic energy impactor"
spacecraft. An alternative
solution would be to use a
"gravity tractor" spacecraft to
hover above the asteroid and
gently pull it slightly off
course using its own gravity.
For now, NASA has decided to
wait and see what’s going to
happen. According to an analysis
by Steven Chesley of the Near
Earth Object program at the Jet
Propulsion Laboratory in
Pasadena, CA, there is no cause
for alarm yet. Apophis will be
swinging by the Earth in 2013,
when it will be in perfect
position to be tracked by the
1000-ft. diameter radio
telescope in Arecibo, Puerto
Rico. The data obtained during
that pass could rule out the
asteroid hitting the keyhole in
2029. But if it isn’t able to
rule out the possibility, there
will still be enough time to
launch a deflection mission.
Schweickart estimates that such
a mission could take as long as
12 years to complete. But for
now, most scientists are content
to wait until we get a better
idea of exactly what the risks
are.
"There’s no rush right now,"
says Chesley. "But if it’s still
serious by 2014, we need to
start designing real missions."
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