Astronomers document ‘failed’ supernova in the Milky Way

Supernovae are not always supernovae. The explosions, which mark the death of a star, are often spectacularly energetic. But every now and then they are a complete failure.

Scientists detailed this Wednesday (1st) one of these failures: an immense star, which had so much of its material deflected by the gravitational force of a companion star in a stellar marriage —called a binary system—, that, when it exploded at the end of its life cycle, he barely managed a groan.

Its final explosion was so tame, in fact, that the collapsed star — now an incredibly dense object called a neutron star — remains in a docile circular orbit with its companion. A more powerful explosion, at the very least, would have resulted in a more oval orbit and might even have sent the star and its companion in opposite directions.

This binary system, studied using a telescope at the Cerro Tololo Inter-American Observatory, based in Chile, is located about 11 light-years from Earth in our galaxy, the Milky Way, in the direction of the constellation Puppis. A light year is the distance that light travels in one year, 9.5 trillion kilometers.

The anemic stellar explosion that occurred has been called an “ultra-stripped” supernova. This happens when a massive star collapses when it runs out of fuel in its core, but fails to explode strongly because a companion star has sucked in much of its outer layers and removed material that would otherwise be violently ejected into space.

“Since there is little material in the stellar envelope, there is almost no material ejected from the collapse shock,” explains astronomer Noel Richardson of Embry-Riddle Aeronautical University, lead author of the study published in the journal Nature.

Study co-author Clarissa Pavão, a physics student at Embry-Riddle, described the explosion as “weak, subtle and passive.”