Twitter Helps Astronomers Zero-In On M51 Supernova

astroengine writes "A tweet about last week's M51 (the 'Whirlpool Galaxy') 14-magnitude bright stellar explosion was picked up by University of California, Berkeley, astronomers... who just so happened to be enjoying some observing time on one of Keck Observatory's monster telescopes. Although the weather wasn't perfect, the Berkeley team were able to quickly observe a spectrum from the M51 brightening to quickly confirm that it was a Type II supernova — the core collapse of a massive star, some 8 times the mass of the sun. 'This is the first time that we've been alerted via a tweet,' Alex Filippenko, lead astronomer of the UC Berkeley team, told Discovery News."