Hubble discovers 'zombie star' haunting the universe
Astronomers discover what could be a supernova survivor, a white dwarf star that may have defied a fiery death.
Quick, call Rick Grimes! It looks like we may have a cosmic zombie on our hands.
Typically, a supernova wipes out the exploding white dwarf star that is unfortunate enough to be caught in the middle of it. It turns out that some stars may survive their own personal apocalypses, leaving behind what NASA describes as a "zombie star."
A team of astronomers combed through data from the Hubble Space Telescope and found a star that appears to have survived (after a fashion) a weak supernova. This type of weak supernova is called a Type Iax, not to be confused with its brighter brethren, which are supernovas called Type Ia. The zombie-producing supernova has been named "SN 2012Z." It sits about 110 million light-years away from Earth.
Hubble managed to capture images of the star's host galaxy several years before the supernova occurred, giving astronomers a before-and-after view of the event. Finding the star remnant was an ah-ha moment.
"I was very surprised to see anything at the location of the supernova," said Curtis McCully, a Rutgers graduate student and lead author of a paper about the discovery which appeared in this week's Nature journal. "We expected the progenitor system would be too faint to see, like in previous searches for normal Type Ia supernova progenitors. It is exciting when nature surprises us."
The existence of a zombie star is currently a hypothesis. The astronomers hope further observations of the area in 2015, after the light from the supernova has dimmed, will confirm the finding. The zombie star may well have more brethren just like it out in the universe. Astronomers have already identified over 30 mini-supernovas that could have survived white dwarfs. That may not be enough to qualify for a zombie-star apocalypse, but it sure sounds like it would make for a great episode of "Star Trek."