A magnetar called XTE J1810-197, discovered in 2003, has just woken up after 10 years of dormancy, blasting out radio waves. In 2008, it simply disappeared from our field of vision.
See also: Dead star comes back to life, astronomers observe
Then, in 2018, it woke up. Only this time, there was something strange about the radiation it was emitting.
Now, scientists have analyzed these radio waves in two separate studies, and the results are terrifying. These low-frequency electromagnetic emissions are twisted in a way we've never seen before, and the star appears to be wobbled.
"Unlike the radio signals we've seen from other magnetars, this one is emitting huge amounts of rapidly changing circular polarization," says astrophysicist Marcus Lower of CSIRO in Australia, who led the original work. "We've never seen anything like this before."
See also: James Webb may have spotted the universe's first stars
All stars are special in their own way, but Magnetars are perhaps the strangest. They are very young neutron stars, which are themselves the destroyed cores of massive dead stars that have gone supernova and ejected most of their material in a colossal explosion. The core that remains collapses under gravity and is dense – up to 2.3 times the mass of the Sun, compressed into a sphere just 20 kilometers wide.
After this collapse process, neutron stars briefly possess an insanely strong magnetic field. They're basically the most magnetic things in the Universe, with magnetic fields 1,000 times stronger than a regular neutron star and a quadrillion times stronger than Earth's.
See also: J0613+52: A special galaxy without stars was discovered!
This makes them behave somewhat strangely. For example, scientists believe that the constant tug-of-war between a magnetar's magnetic field and gravity causes it to explode in giant earthquakes from time to time, sending out bursts of radio waves called fast radio bursts. The recent activity, however, is unprecedented—and could provide new insight into these mysterious stars.
Source: sciencealert
