A team of national and international astronomers have found clues of giant and extremely rare eruptions happening for as long as 3.5 milliseconds and has its genesis from a magnestar located 13 million light years ahead. The report of the eruption was published in Nature and occurred on April 15, 2020. The single vent released energy that is as huge as what the Sun emits in one lakh years.
The research was carried out by astronomers from the Aryabhatta Research Institute of Observational Sciences, Nainital, and from institutes in Norway and Spain.
What are magnetars and how they erupt
Magnetars are isolated stars several light years away and possess intense magnetic fields. When they erupt, they burst in the form of intense eruptions like transient X-ray pulses several notches higher than that of the Sun. Even the most inactive magnetars are thousands of times brighter than the Sun. About 30 magnetars has been discovered in our galaxy, the Milky Way.
The eruption that was recently identified was from a magnetar named GRB2001415.
Magnetars witness starquakes at its crust due to a highly unstable environment due to their magnetospheres. The instability forms Alfven waves familiar to the Sun’s interiors as well and the interaction of multiple Alfven waves releases massive energies, resulting in giant flares that last for a few milliseconds.
What did the detection of the eruptions reveal
Alberto J Castro-Tirado, scientist at the Instituto de Astrofísica de Andalucía, Spain and leda author of the report said, the observations revealed that eruptions can take place for about tens of microseconds and can be much faster than extreme astrophysical transients. The discovery of the eruptions is further significant as GRB2001415 found in a sculptor group of galaxies is the farthest magnetar eruption found so far.
Shashi Bhushan Pandey, one of the co-authors of the study and astronomer at ARIES said detection of eruption of magnetars outside the Milky way is rare.
The detection was made possible by the Atmosphere-Space Interactions Monitor (ASIM) at the International Space Station and its wide effective area and scientists working with complex data analysis. With this the scientists will get to understand how magnetic stresses are formed around neutron stars, said the researchers.