Supernova 4-in-1: Hubble Captures Four Views of One Exploding Star With a Warp in Space-Time
Four supernovas for the price of one? Kind of. For the first time ever, scientists were able to witness multiple angles -- four to be exact -- of a single exploding star.
According to a report from the Hubble Space Telescope website, an international team of researchers from the Stockholm University in Sweden were able to spot a distant type of supernova dubbed the "supernova iPTF16geu" using the Hubble Space Telescope.
The exploding star is far, far away -- so distant that its light took 4.3 billion years to get to Earth. However, the most remarkable feature of this supernova isn't its distance from the planet nor the time it spanned to travel here.
A report from Popular Mechanics revealed that the astronomers were initially puzzled at the unnatural brightness of the supernova. Further analysis led them to realize that the magnified supernova was merely the effect of a galaxy passing in front of it.
The passing galaxy warped the space-time fabric surrounding the exploding star, acting as a lens. It split the light four ways and bent it in a way that boosted its intensity. Lead author Ariel Goobar, professor at the University of Stockholm's Oskar Klein Centre, explained that tracking the arrival times of the four separate images can actually help measure the expansion rate of the universe.
These four images form a circle with a radius of 3,000 light years around the lensing galaxy.
Type Ia supernovae -- also known as standard candles -- consistently shine at the same intrinsic brightness, so astronomers can approximate its distance by how bright it appears. With the newly discovered supernova iPTF16geu, scientists can learn also more about the warping of spacetime on smaller extragalactic scales.
"Resolving, for the first time, multiple images of a strongly lensed standard candle supernova is a major breakthrough," Goobar explained. "We can measure the light-focusing power of gravity more accurately than ever before, and probe physical scales that may have seemed out of reach until now."
This findings are available in a paper published in the journal Science.