- Researchers believe they can now produce
a form of antimatter, which could one day be used to propel spacecraft,
according to the U.K.'s The Guardian newspaper.
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- Results of antimatter experiments, the
power behind the fictional warp drive on Star Trek's USS Enterprise, are
due out this week.
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- Researchers from Fermilab, the U.S. Department
of Energy's particle accelerator laboratory in Illinois, think it's possible
to create atoms of antihydrogen with an efficiency that allows them to
at least study its properties and investigate ways in which it could be
put to use.
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- Antimatter is comprised of antiparticles
that have the same mass and spin as their particle counterparts but have
opposite charge.
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- When antimatter comes into contact with
"normal" matter, the two states annihilate each other, producing
pure energy. Its potential has long been known in science fiction, but
it had yet to be taken seriously since antimatter doesn't naturally exist
on Earth and is extremely difficult to make.
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- Current experimental methods produce
high energy anti-atoms traveling at enormous speeds. One of the researchers'
next aims is to produce antimatter that is almost stationary, allowing
it to be trapped and held within a "magnetic bottle." Confined
in this way, the antihydrogen could be transported into space to provide
power for extended missions.
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- As yet, the quantities required for matter-antimatter
energy creation can't be made, according to The Guardian.
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- "If you want to use pure antimatter
for propulsion you need milligrams and more, and we simply don't have that
yet," says Gerald Smith of Pennsylvania State University's Laboratory
for Elementary Particle Science.
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- Instead, Smith is proposing that smaller
quantities of antihydrogen could be used to trigger nuclear fusion reactions.
"You could store a microgram of antihydrogen and take it into space,"
he says. "That would be enough for a mission."
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- Producing a microgram of antihydrogen
is not beyond the realms of possibility, and storage methods are already
being developed.
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- Funded by NASA's Jet Propulsion Laboratory
and the US Air Force, the Pennsylvania researchers are currently building
a prototype antimatter trap. They also plan to confine antiprotons, one
of the constituents of antihydrogen, within similar magnetic bottles.
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- These antiprotons are easier to produce
than antihydrogen (but more difficult to trap) and could, like antihydrogen,
be used to catalyze nuclear fusion reactions for space propulsion.
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- For the moment, producing enough antimatter
for space propulsion is not on Fermilab's agenda -- federal funds are currently
directed towards making antihydrogen as a means of testing fundamental
theories of physics.
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- "There are not going to be applications
that come directly out of this; it has more to do with the theories we
have about the properties of physical matter," says David Christian
of the Fermilab team.
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- Having improved their production methods,
the Fermilab researchers are now ready to begin a serious investigation
of antihydrogen's properties, The Guardian reports.
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- They are developing ways of examining
the light emitted by antihydrogen atoms when its electrons return to their
standard energy levels after being forced into "excited states."
Hydrogen's behavior in this area is extremely well understood.
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- If antihydrogen's behavior turns out
to be even slightly different, physicists would have to rethink or abandon
many established theories describing the symmetry between matter and antimatter
in the universe.
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