An international team, led by astrophysics professor Peter Garnavich of the University of Notre Dame in Indiana, found two instances of a breakout of a supernova from the center to the surface for the first time.
Only possible because of the Kepler Observatory
Generally speaking, astronomers react to events in space and then train telescopes in response. This however, is not the case with the Kepler Observatory which is trained in a single place and stares at it for years. It was because of this technique and vigilance that the team was able to analyze the data from the Kepler space telescope over a three year period and capture the precise moment when two stars exploded in 2011. These explosions were caused by the core collapse of the stars creating an explosion called a Type II supernova.
This stationary use of telescope for years is the reason that the Kepler has also captured exoplanets as they pass in front of their host stars and why they were able to capture these two breakouts that only lasted about 20 minutes from the core collapse until the shockwave.
While supernovae are largely viewed as explosions that destroy a star but that is not the case with type II supernovae which are caused by the collapse and explosions of the star’s core.
The team was able to study data from three years where the Kepler takes an image every half an hour. The Kepler over this time was covering more than 500 galaxies containing around 50 trillion stars.
The first of the two type II supernovae explosions happen to KSN 2011a located about 700 million light-years from earth and was a star roughly 300 times the size of the our sun. The second happened to KSN 2011d about 1.2 billion light-years from Earth and was an even bigger star about 500 times bigger than the Earth’s sun.
Scientists speak about the supernovae find
With any luck, the Kepler will witness a stars exploding but for now we’re stuck with these two instances. As they are the only two events of these events it’s tough to much in the way of subtlety but if Kepler captures additional”In order to see something that happens on timescales of minutes, like a shock breakout, you want to have a camera continuously monitoring the sky,” Garnavich said in a statement ahead of the study’s publication in Astrophysical Journal. “You don’t know when a supernova is going to go off, and Kepler’s vigilance allowed us to be a witness as the explosion began.”
“That is the puzzle of these results,” said Garnavich. “You look at two supernovae and see two different things. That’s maximum diversity.”
Only KSN 2011a saw a shock breakout.
“All heavy elements in the universe come from supernova explosions. For example, all the silver, nickel, and copper in the Earth and even in our bodies came from the explosive death throes of stars,” said Steve Howell, project scientist for NASA’s Kepler and K2 missions.
“Life exists because of supernovae.”
While the Kepler’s primary job is the search for life on other planets, it’s quite the bonus that it’s helping scientists get a better understand of supernovas which would also be responsible for any live that Kepler might find outside of our solar system.
As Kepler keeps up its mission, things will continue to get interesting as it continues its discoveries.