There’s no smoke without a fire, and there’s no supernova remnant without some evidence of a past supernova explosion. The Jellyfish Nebula, also known as IC 443, is a supernova remnant that has so far remained without a culprit, but scientists have finally observed where the nebula started from.
Astronomers have discovered a pulsar (a rapidly rotating neutron star) on the edge of the nebula by observing IC 443 using the Chandra X-ray telescope. The object is surrounded by a ring of material and it’s emitting a powerful jet. The pulsar has a comet-like tail of dispersed hot gas, which is due to the fact that the star is moving at 800,000 kilometers per hour (about 500,000 miles per hour).
The tail of the pulsar is misaligned compared to the trajectory of the pulsar, which could be due to interactions with the material of the nebula. The tail has also been put forward as an indication that the pulsar is moving inside the nebula and it’s not the remnant of the original supernova. The tail doesn’t show any shock waves (likes a sonic boom in the material), indicating that the pulsar is part of the nebula and the cinder of the supernova that created it.
The Jellyfish nebula is 70 light-years across and it is 5,000 light-years from Earth. It probably formed 30,000 years ago (although some astronomers have suggested a much earlier age of 3,000 years). The new composite image released by NASA reveals a circular structure made of particles from the pulsar wind suddenly being slowed down.
Pulsars form when a star more massive than the Sun goes supernova. Stars at the end of their lives collapse on themselves, and if their mass is right (too big and it will become a black hole), an object made exclusively by neutrons will be left behind after the explosion. Pulsars are incredibly dense: a teaspoon weighs about 5,000 million metric tonnes (5.5 billion US tons).
The research is published in The Astrophysical Journal.