Astronomers have made an exciting new discovery, identifying a newborn pulsar that may possibly be only 14 years old. Scientists were finally able to observe the pulsar after the dense debris and bright energy emissions from the supernova explosion that created the pulsar finally thinned enough. This celestial formation is known as a pulsar wind nebula or a plerion. Found in a dwarf galaxy 395 million light-years from Earth, the object, called VT 1137-0337, was first observed in 2018 through the Very Large Array Sky Survey (VLASS) located in New Mexico, USA. “Based on its characteristics, this is a very young pulsar, possibly as young as only 14 years, but no older than 60 to 80 years,” said Gregg Hallinan, professor of astronomy at Caltech and one of the astronomers who identified the object.
“What we’re most likely seeing is a pulsar wind nebula,” said Dillon Dong, Hallinan’s PhD student and the co-finder of this discovery.
Pulsars are a type of neutron star that is still spinning. As a result of this spin and the extremely heavy density of a neutron star, at least 1.5 times the mass of our Sun but compacted in a radius that is only as wide as a city on Earth, these celestial objects are highly magnetised and shoot out energetic electromagnetic radiation from either of its magnetic poles. These super-dense celestial objects are so dense that a teaspoon of neutron star material would be 900 times heavier than the Great Pyramids of Giza.
Neutron stars are formed when a massive main-class star is compressed under the weight of its own size after it burns through all possible fuel in its core and collapses in a supernova explosion, some of the brightest and most energetic cosmic events. As a result, most of the material of the formerly massive star is expelled while the remainder is compressed down to a neutron star.
VT 1137-0337 is a particularly strong neutron star, being several times more powerful than a similar supernova remnant called the Crab Nebula, which had emitted gamma-ray beams that exceeded measurements of 100 billion electron volts.
“The object we have found appears to be approximately 10,000 times more energetic than the Crab, with a stronger magnetic field. It likely is an emerging ‘super Crab,’” said Dong.
In fact, VT 1137-0337 can be so powerful that it may be classified as a different entity altogether – a magnetar. Magnetars are pulsars that have a magnetic field that are many magnitudes stronger than normal pulsars. But not much is known about magnetars apart from theories about magnetars being the origin of mysterious bursts of radio energy known as fast radio bursts, or FRBs. But VT 1137-0337’s discovery may shed some light on that aspect as well.
“Our discovery of a very similar source switching on suggests that the radio sources associated with FRBs also may be luminous pulsar wind nebulae,” explained Dong.