       psr b1257+12 (psr 1257+12), is a pulsar located 1000 light years from the sun. in 1992, two planets were discovered orbiting the pulsar, and a third was confirmed in 1994. == pulsar == psr b1257+12 is in the constellation of virgo. the designation psr b1257+12 refers to its coordinates in the b1950.0 epoch and it being a pulsar. psr b1257+12 was discovered by the polish astronomer aleksander wolszczan in 1990 using the arecibo radio telescope. it is a millisecond pulsar, a kind of neutron star, and was found to have anomalies in the pulsation period, which led to investigations as to the cause of the irregular pulses. in 1992 wolszczan and dale frail published a famous paper on the first confirmed discovery of planets outside our solar system. using refined methods one more planet was found orbiting this pulsar in 1994. the discovery stimulated a search for planets orbiting other pulsars, but it turned out such planets are rare; only one other pulsar planet, orbiting psr b1620-26, has been confirmed. psr b1257+12 has a rotation period of 6.22 milliseconds (9,650&nbsp;rpm). == planetary system ==      === planets === thumb|right|artist's impression of the planets orbiting psr b1257+12. in 1992, [[aleksander wolszcza
Millisecond_pulsars Planetary_systems_with_three_confirmed_planets Science_and_technology_in_Poland Virgo_(constellation)