It’s virtually impossible to comprehend the scale of a supernova explosion. When a dying star finally explodes into oblivion, the energy emitted is so great that merely writing out the measure of its power becomes surreal: an average bulb will have about 60 watts whereas the biggest supernova explosions have about 220,000,000,000,000,000,000,000,000,000,000,000,000 watts. That’s 580 billion times brighter than the sun.
How about comparing a supernova explosion to an atomic bomb? Surely that’ll make things easier. Well, the Hiroshima blast was created with a piece of uranium smaller than a pea. The biggest supernovas would be equivalent to a bomb created with a hunk of uranium the size of the moon.
And that power has now been captured in visible form for the first time ever.
Using light readings from NASA’s Kepler space telescope, a team led by Peter Garnavich, professor of astrophysics at the University of Notre Dame in Indiana, are able to present our first look at a star’s shockwave, also known as shock breakout, during a supernova explosion.
The particular star in question is KSN 2011d, a red supergiant approximately 500 times bigger and 20,000 times brighter than the sun and about 1.2 billion light years from Earth. “To put their size into perspective, Earth’s orbit about our sun would fit comfortably within these colossal stars,” said Garnavich. This massive star exploded in 2011 and, thankfully, the Kelper was there to capture it.
As for what specifically Kelper captured above, in NASA’s own words:
“When the star’s internal furnace can no longer sustain nuclear fusion its core to collapses under gravity. A shockwave from the implosion rushes upward through the star’s layers. The shockwave initially breaks through the star’s visible surface as a series of finger-like plasma jets. Only 20 minute later the full fury of the shockwave reaches the surface and the doomed star blasts apart as a supernova explosion.”
While finally capturing such a blast is a revelation in and of itself, Garnavich and his team are now investigating why a similar supernova explosion also captured by Kepler in 2011 did not produce a shockwave like the one above. They’re hoping that analyzing these Kelper readings, and many others (some from Kepler’s recent K2 reboot mission), will provide more clues about exactly how and why supernova explosions happen.
Of course, what we already know about supernova explosions is not only wondrous and astounding, but far more relevant to all of us down here on Earth than you might think. In the words of Steve Howell of NASA’s Ames Research Center:
“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. Life exists because of supernovae.”