DES-SN Astronomers Baffled by 72 Super-Bright Cosmic Flashes While Searching for Dark Energy
In the world of astronomy, spotting a change in brightness (usually from a star) can be the key to identifying a new planet or set off speculation about alien megastructures.
More recently, however, 72 bright flashes of light have stirred up a mystery among the team of astronomers on the Dark Energy Survey Supernova Program, or DES-SN.
Despite being as bright as supernovas, these flashes are very short—they only last for about a month at a time, while the afterglow from normal supernovas can last for several months.
The flashes were picked up at the Cerro Tololo Inter-American Observatory, situated in the Andes Mountains, and weren't the initial target of the observations—instead, the DES-SN team were looking for genuine supernovas, which may help give insight into the nature of dark energy.
"The DES-SN survey is there to help us understand dark energy, itself entirely unexplained," said Miika Pursiainen of the University of Southampton. "That survey then also reveals many more unexplained transients than seen before."
We do know two things about these mysterious flashes: they're extremely hot, ranging from 10,000 to 30,000 degrees Celsius, and they're very, very big—they range in size from "several up to a hundred times the distance from the Earth to [the] Sun," which is a distance of 150 million kilometers.
Despite have a much shorter period of brightness, these bright flashes might still be supernovas—astronomers recently discovered the fastest, brightest supernova yet, and even created a hypothesis for what made it so brief: instead of a normal death, the star "exhaled" a dying breath of dense gas, which enshrouded it.
Upon the actual explosion of the star, the shroud of gas ignited, creating a quick, bright flash, rather than an extended glow.
Short, fast supernovas are rare, but this new discovery may point to the existence of many more.