First confirmed discovery of planets outside our solar system, 1990
PSR B1257+12 was discovered by the Polish astronomer Aleksander Wolszczan in 1990 using the Arecibo radio telescope. In 1992 Wolszczan and Dale Frail published a famous paper on the first confirmed discovery of planets outside our solar system. Read more
The first extrasolar planets were detected around pulsars. These neutron stars in rapid rotation, with a period of one millisecond to one second, emit relativistic stellar wind, carrying a magnetic field that interacts with the bodies orbiting the pulsar. Electromagnetic phenomena were calculated by two astronomers, one of the Paris Observatory. They showed that the planets could then emit radio waves that would detect them, and that the small bodies could undergo rapid changes orbit in less than 10 000 years. The first three planets were discovered outside the solar system (in 1992) revolve around a very strange star with the sweet name "PSR 1257 +12": if its mass is comparable to our sun, its diameter would not exceed 40 km (as against 1.4 million km for the Sun).
PSR B1257+12, sometimes abbreviated as PSR 1257+12, is a pulsar located 980 light-years from the Sun. As of 2007, it is confirmed that three extrasolar planets orbit the pulsar. Read more
Three small bodies were found in orbit around the pulsar PSR 1257+12. They have been designated "PSR1257+12 AA ..BA and ..C". These planets are believed to have formed after the supernova that produced the pulsar.