Photo credit: YouTube/NASA Ames/ STScI/G.Bacon
By Michael Slezak
The final violent death throes of a star has been seen with visible light for the first time and provided a fresh mystery for astronomers.
Scientists think shock breakouts – a shockwave and flash of light that rocks a massive star just before it explodes into a “supernova” – allow the stars to finally explode, spewing out all the heavy atoms that exist in the universe.
But actually watching that process occur and seeing how it progresses has proved elusive, leaving scientists guessing about exactly how it happens.
By sifting through three years of data collected by Nasa’s now half-broken Kepler space telescope, an international team of scientists have now seen the elusive shock breakout occur. The problem is, it seemed to happen in only one of two exploding stars observed.
In data collected in 2011, they found two supernovae begin, potentially capturing the crucial moment. However only one star seemed to have the shockwave. An author on the paper, Brad Tucker from the Australian National University, said that was a mystery. He said the shockwave was thought to ripple across the surface and actually allow the supernova to explode.
“We’ve always thought that this is the physical mechanism that allows the star to blow up,” he said. “So gravity collapses the core down, and once the pressure is too much, you create a neutron star or sometimes a black hole, the rest of the energy rebounds and causes the star to blow up.
“It’s been this fundamental thing that we’ve always thought occurs but we’ve never seen it take place.”