The Eta Carinae system is not only one of the brightest and most spectacularly large stars in our galaxy, but it’s also one of the most famous. If you, for whatever reason, are not familiar with it, this ticking time-bomb is situated between 7,500 to 8,000 light-years from Earth in the constellation of Carinae.
Calling it a ticking time-bomb refers to the fact that this high-mass star system, which has the combined mass of 90 Suns, has reached the point in its evolution that it could literally go supernova (maybe even hypernova) at any moment, hurtling its guts out into space in a catastrophic way.
Back in the 19th century, for a solid twenty years, this system spat out so much light, it became more luminous than pretty much any other star hanging in our sky. It was so bright, in fact, that, because of the frequency of its ‘supernova-esque’ outbursts, astronomers now refer to this period of time as “the great eruption.”
Since then, astronomers have learned that, over the course of those two decades, the system ejected the mass of well over ten Suns. To this day, it continues to shed material, but at a much slower rate (it’s estimated that it’ll lose another Sun-worth of mass if it continues unabated in 1,000 years).
This image of the system, which shows “low energy X-rays in red, medium energy X-rays in green, and high energy X-rays in blue,” showcases several notable features, including the bow shock that’s produced when each star’s solar winds combine, along with the expanding shell of material that encompasses them.
"The blue point source is generated by the colliding winds, and the diffuse blue emission is produced when the material that was purged during the Great Eruption reflects these X-rays. The low energy X-rays further out show where the winds from the two stars, or perhaps material from the Great Eruption, are striking surrounding material. This surrounding material might consist of gas that was ejected before the Great Eruption," according to NASA.