Magnetar: a cataclysmic explosion in 13 million light years

Magnetar: a cataclysmic explosion in 13 million light years


Several million years ago, a magnetar broke loose, releasing as much energy as a billion suns in a fraction of a second. Last year, an instrument available to the Lord of the ISS was able to capture this incredible event. Astronomers believe these high-energy explosions are caused by “starquakes”.

Neutron stars and magnetars

A neutron star is formed when the core of a massive star collapses at the end of its life under the effect of gravity. As the star dies in a supernova, it ultimately leaves behind a small object composed almost entirely of neutrons held together. Physically, a neutron star represents approximately 1.3 to 2.5 solar masses (approximately 330,000 Earths) crammed into a sphere measuring only twenty kilometers in diameter.

Magnetars are neutron stars whose magnetic fields are at least a thousand times stronger than those of other neutron stars.

We know that these objects, which can be thousands of times brighter than our Sun, can “ignite” dramatically. Unfortunately for researchers, these rashes are often very sudden and incredibly brief, and therefore difficult to study. However, difficult does not mean impossible. Recently, a team of astrophysicists recorded one of these events.

A cataclysmic eruption

The magnetar in question is located in the Sculptor’s Galaxy, a spiral galaxy found about thirteen million light years from Earth. The eruption was detected on April 15, 2020 by the Atmosphere-Space Interactions Monitor (ASIM) instrument, available on the International Space Station.

Analyzes show that this distant object released as much energy as our Sun produces in 100,000 years, in just 0.16 seconds, before suddenly “extinguishing” itself.

“It is as if this magnetar had decided to reveal its existence” from its cosmic solitude “by shouting in the void of space with the force of a billion suns”, underlines Alberto J. Castro-Tirado, of the ‘Institute of Astrophysics of Andalusia of the Spanish Council.

In the journal Nature, the authors point out that they spent more than a year analyzing data from ASIM, dividing the event into four phases based on the energy output of the magnetar and changes in its magnetic field.

This new study is important because only about 30 magnetars have been identified out of around 3,000 known neutron stars. In addition, it is the most distant eruption detected to date for such an object. Astrophysicists suspect that these events could be caused by so-called “starquakes” capable of disrupting the very “elastic” outer layers of magnetars.