April 4, 2003
Samples of the Future
Credit: The crew of the International
Space Station, NASA
Explanation: Many years from now, space travelers
will zip around the solar system in extraordinary spaceships.
Meteoroids? No problem. Punctures in the hull will heal themselves.
Radiation? Astronauts will be shielded from the most powerful
cosmic rays. Low on fuel? Impossible. The craft will be propeled
by inexhaustible sunlight pressing against a lightweight solar
sail–kilometers wide yet only a few molecules thick.
How do you make such a super-spaceship?
The first step is to find the right building materials. That’s
the goal of MISSE (pronounced "Missy"), short for the
Materials International Space Station Experiment. Pictured
above, MISSE consists of two suitcase-like containers filled
with hundreds of advanced materials. The suitcases are opened
and mounted outside the space station’s Quest airlock where the
samples are exposed to the ravages of space.
MISSE was delivered to the ISS
in late 2001 and "it’s doing great," says Bill Kinard
of NASA’s Langley Research Center. "Frequent crew
photographs show that most of our test specimens are not
being adversely affected by the space environment, just as we
hoped. A few samples have been physically damaged–perhaps from
meteoroid or man-made debris impacts, atomic
oxygen erosion, or even rocket blasts from docking spacecraft.
We’ll find out more when they are retrieved by astronauts during
a future spacewalk."
A new batch of MISSE samples
is ready for launch when the space shuttle returns to flight.
"They’ll replace the samples that are on the ISS now,"
says Kinard. Among the new samples will be some stowaways: "approximately
4 million Basil seeds
that we plan to distribute to students for science projects on
the effects of the space exposure," he explains. It’s a
little something extra for the future passengers of those super-spaceships. | 
