The shockwave resulting from an explosion of a giant star, also called as a “shock breakout,” has been captured for the first time by the Kepler space telescope.
An international team of scientists, headed by Peter Garnavich, a University of Notre Dame professor, analyzed and studied the light captured by Kepler from 500 galaxies every 30 minutes for a period of three years. This, NASA notes, amounted to some 50 trillion stars. Through this study, the team was looking for signs of stellar death explosions that are also called supernovae.
Brad Tucker, of the Australian National University who was also the study co-author, said the latest discovery will help scientists understand and study the life cycles of stars.
“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. “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.”
The explosion of two stars in 2011 was caught by Kepler’s view. While the first of these stars (also called as red supergiants), the KSN 2011a, is 300 times the size of the sun and is as many as 700 million light years away from our planet, the second, KSN 2011d, is 500 times the size of the sun and 1.2 billion light years away.
“To put their size into perspective, Earth’s orbit about our sun would fit comfortably within these colossal stars,” Garnavich said.
The shockwave was observed around the smaller star, which started collapsing and contracting as its fuel started running out.
“It’s like packing in dirt,” Tucker said, explaining how a supernova occurs. “You keep pressing it till it’s so dense you can’t get it in anymore, and that’s when you create a neutron star. But you reach a limit when you can’t pack it in anymore, and that force pushing in bounces back and it triggers a shockwave to go through the star, causing the star to actually blow up.” This is when elements like gold, silver and platinum are created by the supernova.
According to Discovery News, the first Kepler space observatory mission, K1, discovered the first exploding red giants. Three supernovae that have been previously found in the mission came from old white dwarfs; with another one that is yet to be analyzed. The second Kepler mission, K2, began in 2014 after repairs were made to the telescope. It has since found in excess of 20 supernovae.