First super-Earth extrasolar planet discovered

In 1992, two "super-Earths" – planets more massive than Earth but substantially less massive than our own gas giants – were discovered orbiting the pulsar PSR B1257+12 (also known as Lich). The two planets were named Poltergeist and Phobetor by the International Astronomical Union in 2015.

These two planets are around four times as massive as Earth. Their parent pulsar, which is around 2,300 light years away, is the remnant of a supernova – an event that nearby planets were not thought to be capable of surviving. It is possible that debris from the supernova led to a second round of planet formation around the pulsar.

As of January 2016, a third planet in this system, Draugr, is the least massive of any known extrasolar planet.