This artist's illustration shows supernova 2013ge, with its companion star at lower right. The companion star is impacted by the blast wave from the supernova, but not destroyed. Over time astronomers observed the ultraviolet (UV) light of the supernova fading, revealing a nearby second source of UV light that maintained brightness. The theory is that the two massive stars evolved together as a binary pair, and that the current survivor siphoned off its partner's outer hydrogen gas shell before it exploded. Eventually, the companion star will also go supernova. Credit Artist Illustration: NASA, ESA, Leah Hustak (STScI)

Supernova Survivor Revealed by Hubble

By Carolyn Mathas Last updated May 12, 2022

NASA’s Hubble Space Telescope uncovered a companion star previously hidden in the glare of its partner’s supernova. The discovery marks the first time astronomers have found a supernova without evidence of the star’s atmosphere in its makeup.

Astronomers can detect the signature of the elements propelled through space in supernova explosions. A star’s outmost layer contains hydrogen. If there is no hydrogen in the expulsion, there was none when the star exploded. Hydrogen loss was a mystery, and astronomers have been using Hubble to search for clues and test theories to explain these stripped supernovae.

The new Hubble observations support the theory that an unseen companion star siphons off the gas envelope from its partner star before it explodes.

Now that astronomers have been lucky enough to identify the surviving companion star, they can use it to work backward and determine the characteristics of the star that exploded and now have the unprecedented opportunity to watch the survivor and the aftermath of the supernova.