StarDate: October 30, 2009

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A hidden pulsar may lurk nearby, beaming energy and charged particles into the galaxy like a cosmic lighthouse. The particles carom off other particles of matter and twirl through strong magnetic fields, hiding the pulsar's location. But a space-based telescope may have detected its presence in the form of high-energy cosmic rays -- the charged particles flung into space by the pulsar's own strong magnetic field.

The observatory is the Fermi Gamma-Ray Space Telescope. It was launched last year to study some of the most powerful objects in the universe -- from exploding stars to "jets" of energy shooting away from black holes. Earth's atmosphere prevents gamma rays from reaching the surface, so the only way to see them directly is to loft a telescope above the atmosphere.

Fermi can also search for cosmic rays -- solid particles that are flung into space by some of the same objects that create the gamma rays.

During its early months of operation, Fermi detected a lot more of the most powerful cosmic rays than expected. Another satellite found the same thing.

These cosmic rays could come from collisions between particles of dark matter. But several ground-based experiments have found no evidence of these collisions.

Another possible explanation is a nearby pulsar -- the crushed remnant of an exploded star. It spins rapidly, beaming energy and particles into space -- particles that may have been detected by the Fermi telescope.

Script by Damond Benningfield, Copyright 2009

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