THE PULSAR PLANET

PSR B1257+12 B

The first ever exoplanet outside of our Solar System to be uncovered by Dale Frail and Aleksander Wolszczan in 1992 completely turned our ideas of how planets are made on their head. This is because it was found around a dead, radio and X-ray jet-beaming pulsar; these are essentially the corpses of massive stars that have endured the almighty explosion of a supernova. Frail and Wolszczan used pulsar timing measurements to look for irregularities in its otherwise regular pulsations and they struck lucky, uncovering two planets – one over three times the mass of Earth and the other just over four.

In a supernova explosion, the star is obliterated, leaving behind a tiny dense core that becomes the pulsar. The shock waves that erupt in this event’s wake would destroy any orbiting planets. So how were planets able to still exist around the pulsar after such a violent event? One suggestion is that the gas and dust set to make the planet arrived at the end of the star’s life, blown off the star in outbursts, or possibly part of the debris from the explosion.