SPACE — Scientists were stunned when they watched a dying neutron star with one of the strongest magnetic fields in the cosmos suddenly come back to life. The reactivation of highly magnetic neutron stars or magnetars does not fit the current understanding of such exotic celestial objects.
The research team discovered the magnetar’s return from the dead when they noticed a strange radio signal from the remains of the closest star to Earth, XTE J1810-197, located about 8,000 light years away. The team used the CSIRO Parkes Radio Telescope, Murriyang and the results have been published in the journal Nature Astronomy.
Most magnetars emit polarized light, light with waves oriented in one particular direction. However, the new findings show that the magnetar’s light is circularly polarized, appearing to spiral as it moves through space. This was not only unexpected, but also unprecedented.
“Unlike radio signals we’ve seen from other magnetars, this magnetar emits a large amount of rapidly changing circular polarization. We’ve never seen anything like this before,” research team leader and CSIRO scientist Marcus Lower said in a statement.
Also read: New findings, baby stars shoot out wisps of magnetic flow during their formation
XTE J1810-197 Very Extreme
Illustration of a magnetar with a strong magnetic field and jets. Image: Space.com
Magnetars, like all neutron stars, are born when massive stars die. When stars run out of fuel for the nuclear fusion of hydrogen into helium in their cores, they no longer have the energy to resist the pull of their own gravity.
When the tug-of-war between gravity and radiation pressure ends, the star’s outer layers are thrown outward in a supernova explosion, causing the dying star to lose most of its mass. This leaves the star’s core with a mass between one and two times the mass of the sun, collapsed until it is only about 20 kilometers wide.
Because of this, the material that makes up a neutron star is so dense. One teaspoon of material from the star’s corpse weighs up to 10 million tons.
Rapid core collapse also causes neutron stars to increase their rotation rate significantly. Some newly formed neutron stars can rotate as fast as 700 times per second.
Also read: New research reveals the condition of the Earth when the sun dies
The collapse of the star’s core has other consequences. The magnetic field lines of the dying star are squashed, causing the strength of the magnetic field to increase. As a result, some neutron stars have magnetic fields one quadrillion (1 followed by 15 zeros) times stronger than the sun’s magnetic field. This qualifies them to be magnetars.
Detections of streams of radio waves from magnetars are extremely rare, and XTE J1810-197 is only one of a handful of magnetars known to produce them. The XTE J1810-197 was first seen emitting radio waves in 2003, then went silent for more than a decade.
2024-04-13 01:04:02
#Wreck #Extreme #Star #Universe #Suddenly #Life #Space #Space
