A Field Guide to Alien Planets

Pulsar planets

The first true discovery of extrasolar planets came in 1994, when radio astronomers discovered worlds around the pulsar PSR B1257+12, about 980 light-years away in the constellation Virgo. A pulsar is not a normal star, but a dense, rapidly spinning remnant of a supernova explosion. The oldest exoplanet known yet, PSR B1620-26 b, nicknamed Methuselah, is also a pulsar planet, located 5,600 light years from Earth in the constellation Scorpius.

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Ragnar Larsen