The last star to go supernova in the Milky Way—that astronomers know of—exploded in 1604, before Galileo first turned a telescope to the heavens. But with a neutrino detector now being built within a Japanese mountain that could come online as early as 2016, researchers might be able to do something as yet undone: Make detailed observations of a supernova in our galaxy before it visibly explodes. First, astronomers would be alerted to the unfolding event by the flood of neutrinos generated when a supernova collapses. Within minutes, they could determine the general area of the sky where the explosion would occur, point their infrared telescopes in that direction, and wait for the fireworks. (Outer portions of a supernova aren’t disrupted until anywhere from a few minutes to a few hours after the core collapse and neutrino burst occur, the researchers note.) An exploding star known as Tycho's supernova (image) brightened the Milky Way in 1572. With the new sensor in place, instruments—especially infrared telescopes—would have an almost 100% chance of observing the next supernova in our galaxy, the researchers report in an upcoming issue of The Astrophysical Journal. But because the Milky Way contains a lot of dust, which effectively blocks visible light, the chances of anyone seeing that explosion in the nighttime sky are 20% or less, the researchers note. Odds are somewhat higher for people in the Southern Hemisphere, though, because many more of the galaxy’s stars are visible from there. At current estimated rates of supernova formation in the Milky Way, the odds of one popping off in the next 50 years could be as high as 90%.
*Correction, 1 November, 11:19 a.m.: This article has been revised to more accurately reflect the probabilities of a supernova occurring in the next 50 years.