Mysterious object near center of Milky Way may be unusual star

Science : Objects at the center of the Milky Way are obscured by dense clouds of gas and dust. One of those objects, G2, was detected to be on a near-collision course with the supermassive black hole believed to be at the center of the Milky Way. Initial observations suggested that G2 was a gas cloud, so it was expected that, as it neared the black hole, it would be torn apart and release bright radiation. But it didn’t. Andrea Ghez of UCLA and her colleagues used the Keck Observatory to study G2 as it passed by the galactic center. Because IR images revealed that G2 had continued along its orbit, Ghez’s team concluded that G2 must instead be a large star hidden inside a cloud of dust. Their calculations indicate that the star has a mass twice that of the Sun, but a radius 100 times larger. Other researchers argue that even if G2 were just a cloud of gas, it would have stretched and compressed without any significant release of radiation. Further evidence is likely necessary to clearly prove which hypothesis is correct.