Alicia Soderberg and Edo Berger of Princeton University were the alert astronomers: on January 9 they were using NASA’s Swift satellite’s X-ray telescope to observe a distant spiral-shaped galaxy, known as NGC 2770. Thanks to the telescopes high sensitivity, at 9:33AM the scientists noticed a powerful burst of X-rays coming from the galaxy, which lasted for 5 minutes before fading away. The lucky part is that the telescope happened to be directed towards the right place at the time the star burst – even before Soderberg and Berger saw the after-effects of the X-rays. The scientists immediately realized the importance of their observation and quickly organized a plan to use telescopes in space and on Earth to follow-up Swift’s discovery. 

Over the next few weeks, observations made by NASA’s Hubble Space Telescope and Chandra X-ray Observatory, along with Swift and other major telescopes, showed beyond a shadow of a doubt that the January 9 X-ray burst indicated the explosion of a giant star.The X-rays were due to a powerful blast wave bursting through the star’s outer layers. The blast wave itself was triggered deep inside the star, when the “nuclear engine” at its center ran out of fuel and collapsed. 

"For years we have dreamed of seeing a star just as it was exploding, but actually finding one is a once in a lifetime event," says Soderberg." This newly born supernova is going to be the Rosetta stone of supernova studies for years to come." Neil Gehrels, Swift lead scientist of NASA’s Goddard Space Flight Center, adds: "It was a gift of nature for Swift to be observing that patch of sky when the supernova exploded. But thanks to Swift's flexibility, we have been able to trace its evolution in detail every day since." 

TFOT has covered other X-ray related space-stories, such as the observation of a light echo from an enormous X-ray flare, which was apparently produced when a single star was disrupted by a super-massive black hole, and the youngest known pulsing neutron star, which has been observed to produce magnetar-like X-ray bursts on two separate occasions. Other related TFOT stories include the Brightest Supernova Ever, observed by NASA's Chandra X-ray Observatory, and the Red Novae, which is a new type of supernovas. 

More information on the NGC 2770 burst can be found in NASA's press release.