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starship-design: antimatter fountain: popsci article


it sounds like science fiction: a fountain of antmatter
spewing from the center of our galaxy. but that is just what
astronomers claim they have discovered, using nasa's compton
gamma ray observatory satellite. 

launched into eart orbit six years ago, the observatory 
monitors the heavens for emissions of gamma rays. in april,
a research team led by astronomers at northwestern univ. 
and the naval research lab. in washington announced that the
observatory had foudn gamma rays emanating from a fountain-
shaped region that appears to originate at the milky way's
center. the high energy gammy-ray emissions were measured
at 511,000 electron volts - precisely the energy produced
when positrons (the antiparticles of electrons) are 
annihilated by collisions with normal matter. "its an 
unmistakable signature of the annihilation" says charles
dermer, a theorist at the navy lab who is helping to 
interpret the findings. 

what could be generating the positrons? on earth, positrons
are produced by the decay of certain radioactive isotopes
but are quickly destroyed when they collide. dermer and 
colleague jeff skibo point out that positrons are also
produced by supernovas, explosions of massive stars. 
successions of supernovas at the milky way's center could
have sent a fountain of hot gases, mixed with positrons,
shooting high above the galactic plane. mingling with the
hot gad would destroy the positrons and produce the observed
gamma rays, astronomers say.

however, other scientists have proposed a different source for
the positrons: one or more black holes believed to exist at 
the galaxy's center.

by andrew chaikin

so guys, what do you think of this? id like to hear
what you think... if its true or not, if they got anything
wrong... etc etc.