Media Release from ICRAR, International Centre for Radio Astronomy Research
A super-dense star formed in the aftermath of a supernova explosion is shooting out powerful jets of material into space, research suggests.
In a study published this week聽a team of scientists in the Australia and the Netherlands discovered powerful jets blasting out of a double star system known as PSR J1023+0038.
It was previously thought that the only objects in the Universe capable of forming such powerful jets were black holes.
PSR J1023+0038 contains an extremely dense type of star astronomers call a neutron star, in a close orbit with another, more normal star nearby.
It was first identified as a neutron star in 2009 but it was only when the research team observed the star with the Very Large Array radio telescope in the United States in 2013 and 2014 that they realised the star was producing much stronger jets than expected.
Astronomer James Miller-Jones, from the International Centre for Radio Astronomy Research (ICRAR), says neutron stars can be thought of as stellar corpses.
鈥淭hey鈥檙e formed when a massive star runs out of fuel and undergoes a supernova, and the central parts of the star collapse under their own gravity,鈥� he says.
鈥淭hese things are typically about one and a half times the mass of the Sun and yet they鈥檙e only 10-15km across, so they鈥檙e incredibly dense.鈥�
ASTRON astronomer Adam Deller, who led the research, says neutron stars and black holes are sometimes found in orbit with a nearby 鈥渃ompanion鈥� star.
鈥淕as can then flow from the companion star to the neutron star or black hole, producing spectacular displays when some of the material is blasted out in powerful jets at close to the speed of light,鈥� he says.
鈥淔rom what we had seen previously, black holes were previously considered the undisputed kings of forming powerful jets, even when they were only fed by a little bit of material from their companion star.鈥�
鈥淚n comparison, neutron stars seemed to make relatively puny jet, which only became bright enough to see when the neutron star was gobbling gas from their companion at a very high rate.鈥�
Dr Deller says when the team looked at PSR J1023+0038 it was only consuming a trickle of material and should have been producing a very feeble jet.
鈥淏ut our observations suggest its jets are nearly as strong as you鈥檇 expect from a black hole,鈥� he says.
Dr Miller-Jones says PSR J1023+0038 is a 鈥渢ransitional鈥� neutron star, spending years at a time powered mainly by the rotation of the neutron star but transitioning occasionally into an active gathering state, when it gets much brighter.
鈥淭wo other transitional systems are now known and both of these have also been shown to exhibit powerful jets,鈥� he says.
鈥淭his is casting neutron stars in a new light and showing that in fact they can sometimes launch jets to rival those coming from black holes.鈥�
The research was published in the Astrophysical Journal.
聽ICRAR is聽a joint venture between 麻豆直播 and The University of Western Australia with support and funding from the State Government of Western Australia.
