Keith Miller/Caltech/IPAC – SELab The end of a star’s life can be an extremely violent event. Once it runs out of fuel, its core collapses, and if its original mass is large enough, it can erupt in a supernova, a runaway nuclear fusion event that can release as much energy as the Sun will produce over its entire lifespan of roughly ten billion years. The remains are either a neutron star, an immensely dense lump of matter, or a black hole. Now, scientists believe they may have observed a star dying in real time. They watched as the star, once one of the brightest in the Andromeda galaxy, quietly winked out of existence. Columbia University astronomer Kishalay De and his colleagues analyzed 15 years’ worth of data collected by NASA’s NEOWISE spacecraft as part of an effort to measure changes in the amount of infrared radiation millions of stars emit over the years. One star, dubbed M31-2014-DS1, stood out like a sore thumb — brightening in 2015, fading roughly a year later, and eventually disappearing …