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Credit & Copyright: Dan Durda (FIAAA,
B612 Foundation)
Explanation:
How would you change the course of an
Earth-threatening
asteroid?
One possibility - a massive spacecraft that uses gravity as a towline -
is illustrated in this artist's vision of a gravitational
tractor in action.
In the hypothetical
scenario worked out
in 2005 by Edward Lu and Stanley Love at NASA's
Johnson
Space Center, a 20 ton
nuclear-electric
spacecraft tows a 200 meter diameter asteroid by simply hovering
near the asteroid.
The spacecraft's
ion drive
thrusters are canted away from the surface.
Their slight but steady thrust would gradually and
predictably alter the course of the tug and asteroid, coupled by their
mutual gravitational attraction.
While it sounds like the stuff of science fiction,
ion drives do
power existing spacecraft.
One advantage of using a gravitational tractor is that
it would work regardless of the asteroid's
structure.
Given sufficient warning and time,
a gravitational tractor could
deflect the path of an asteroid known to be on a collision course
enough to miss planet Earth.
APOD Public Talk Tonight:
Howard Astronomical League,
Columbia, MD
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NASA Web Site Statements, Warnings, and Disclaimers
NASA Official: Jay Norris. Specific rights apply.
A service of: LHEA at NASA / GSFC
& Michigan Tech. U.
Based on Astronomy Picture
Of the Day
Publications with keywords: asteroid
Publications with words: asteroid
See also: