[meteorite-list] Former Astronaut, Engineers Hope to Deflect Asteroid

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Fri Dec 17 12:16:31 2004
Message-ID: <200412171716.JAA19981_at_zagami.jpl.nasa.gov>

http://www.voanews.com/english/2004-12-17-voa3.cfm

Former Astronaut, Engineers Hope to Deflect Asteroid
By Mike O'Sullivan
Voice of America News
17 December 2004

Hollywood films have dramatized an event that scientists say could one
day happen. An asteroid approaches the earth, threatening the planet,
and a team of daring astronauts travels to space to stop it. Some
scientists and engineers say the films were not realistic, but that the
threat is real.

In the 1998 film Armageddon, Bruce Willis and his team landed on an
asteroid and used a nuclear weapon to destroy it. Scientists say the
movie was not accurate in its science, but that its central premise was
authentic. An asteroid could one day strike the earth with devastating
results.

Damage from 1908 asteroid that exploded over Siberia
Trees lay strewn across the Siberian countryside 45 years after a
meteorite struck the Earth near Tunguska, Russia

In the past 600 million years, collisions with space objects have caused
five mass extinctions. The best-known collision, 65 million years ago,
helped kill off the dinosaurs. But the worst, nearly 200 million years
before that, eliminated more than 90 percent of life on the planet. More
recently, the 1908 explosion of an asteroid over Siberia flattened 2,000
square kilometers of forest.

Two years ago, a group of scientists, engineers, and astronauts created
an organization to prevent another cosmic collision. Called the B612
foundation, it takes its name from the asteroid that was home to the
fictional Little Prince in the story by French writer Antoine de
Saint-Exupery.

Former astronaut Rusty Schweickart, chairman of the foundation, spoke
about its goal at the Planetary Society in Pasadena, California. "To
deflect an asteroid in a controlled manner by 2015. And we're not saying
to write a paper about it, to think about it, to talk about it. We're
saying our goal is to deflect an asteroid, that is, to move an asteroid,
to change its orbit, by 2015," he says.

Mr. Schweickart was the lunar module pilot on the Apollo Nine mission in
1969, and he is urging the U.S. space agency, NASA, to support the
deflection project.

He says it could be incorporated into an existing NASA program called
Prometheus, which will send a nuclear-powered spacecraft to explore
three of Jupiter's icy moons, and has a scheduled launch date of 2011 or
later.

Scientists believe there are more than 1,000 near-earth asteroids at
least one kilometer in size, but the likelihood is low that one that big
will hit earth in the near future. So Mr. Schweickart wants the
demonstration done on a smaller asteroid. "The smaller they are, the
more frequent, therefore we pick not the crowd-killer of a one kilometer
or something like that. It's only going to come once every million or
two million or 10 million years. Instead, we wanted to pick something
that was relatively frequent, a 200 meter object," he says.

A collision of an object of that size with the earth would cause a blast
equivalent to hundreds of megatons of explosives.

Advocates of the project say an asteroid can be deflected to a safer
trajectory with a tiny nudge of less than one centimeter per second, if
the mission is undertaken at least a decade before the projected collision.

In the movie Armageddon, the astronauts used a nuclear bomb to destroy
the approaching asteroid, but that, says Mr. Schweickart, is not a good
idea. Most 200 meter asteroids are piles of rubble, and one or more of
the pieces could hit the planet. Moreover, says Dan Durda, senior
scientist with the Southwest Research Institute, asteroids are rich in
minerals and offer opportunities for extraterrestrial mining. "You can't
mine an asteroid by nuking it. The same technologies that we're going to
be demonstrating or hope to demonstrate in this particular case to move
or deflect an asteroid to protect the planet, are exactly the same
technologies and capabilities and techniques that we're going to be
using to move an asteroid around the solar system to mine them and
utilize them for their resources," he says.

It is not likely a large asteroid will collide with earth soon, but Mr.
Schweickart and his colleagues say it is only a matter of time before
one hits us. They add that for the first time in our planet's history,
we have the technology to prevent it.
Received on Fri 17 Dec 2004 12:16:23 PM PST