gamma rays

Whilst carrying out its normal workaday duties of scanning corners of the universe billions of light years from Earth, the Fermi Gamma-Ray Space Telescope has made a discovery that hits decidedly closer to home: lightning strikes on Earth carry the signature of antimatter.

Gamma ray flashes detected in terrestrial storms were of the decaying-positron variety, indicating not only that lightning can produce the antimatter equivalent of electrons, but also that somehow the electric field normally produced by a lightning storm somehow reversed.

NASA's Fermi Gamma Ray Space Telescope spent a year collecting data from a thousand gamma ray sources and came up with this, the best map to date of the extreme universe. It also gave Einstein a shot in the arm by confirming the scientist's theories of space-time.

Friends of the Dark Side, your time may soon be at hand. It seems we have a literal death star aiming in our general direction. The culprit is part of a binary star system—two stars which orbit each other—by the name of WR 104. Both are massive and very, very hot. One will eventually explode into a harmless supernova, providing us with a lovely astronomical light show. The other, however, might be deadly.

Swift is the first satellite explicitly designed to solve the mystery of gamma-ray bursts, the enigmatic explosions that have puzzled astronomers for decades. Practically every day, another burst randomly appears in the sky, flashing powerful gamma rays for anywhere from a fraction of a second to two minutes. Before the burst fades, Swift quickly locates it, rotates its telescopes and other satellites for observation, and relays the burst's location to ground-based telescopes, which study it in detail.