Rare luminous blue variable provides stellar spectacle for Hubble anniversary

Marking the Hubble Space Telescope’s 31st year in space, astronomers focused on AG Carinae, a rare luminous blue variable with up to 70 times the mass of the Sun and a million times the luminosity. One of the brightest stars in the Milky Way, AG Carinae is one of only about 50 luminous blue variables in the local group of nearby galaxies. Like its brethren, it will live fast and die young, burning through its nuclear fuel at a prodigious rate to generate the outward pressure needed to offset the inward crush of gravity. About 10,000 years ago, the star experienced a titanic eruption, blowing off its outer layers and creating a spectacular cloud of debris now some 5 light years across containing roughly 10 times the mass of the Sun. Such outbursts occur once or twice in the short lifetime of a luminous blue variable, a result of the constant tug-of-war between gravity and the radiation pressure generated by nuclear fusion in its core. When the fuel runs out and fusion finally halts, the core likely will implode in a supernova blast.

AG Carinae. Image: NASA, ESA, STScI

A video produced by NASA’s Goddard Space Flight Center highlights the Hubble observation and looks back on 31 years in space: