Astronomers have found a large, fast aging star that has never been seen in the Milky Way galaxy. They have found this star using Hubble Space Telescope.
Since the star is so different, astronomers have named it Nasty 1, a play on its catalog name of NaSt 1, it is located 3,000 light years from Earth.
Astronomers believe that the strange star may represent a brief transitory stage in evolution of extremely massive stars.
The star was first discovered decades ago, and identified as Wolf Rayet star, a rapidly evolving star that is more massive than the sun. The star losses its hydrogen out layers quickly and exposing its super hot and bright helium burning core.
But Nasty 1 doesn’t look like a typical Wolf Rayet star.
Jon Mauerhan of the University of California, Berkeley, and study leader said, “We were excited to see this disk-like structure because it may be evidence for a Wolf-Rayet star forming from a binary interaction, there are very few examples in the galaxy of this process in action because this phase is short-lived, perhaps lasting only a hundred thousand years, while the timescale over which a resulting disk is visible could be only ten thousand years or less.”
The star evolves quickly but as is begins to run out of hydrogen, it swells. Researchers believe that this can happen much faster compared to the life of other stars and Nasty 1 is believed to be only few thousand years.
Nathan Smith of the University of Arizona in Tucson, and co-author of the study said, “We’re finding that it is hard to form all the Wolf-Rayet stars we observe by the traditional wind mechanism, because mass loss isn’t as strong as we used to think, mass exchange in binary systems seems to be vital to account for Wolf-Rayet stars and the supernovae they make, and catching binary stars in this short-lived phase will help us understand this process.”
It was not an easy task to observe Nasty 1. The star is heavily covered by gas and dust and it even blocked the view of Hubble telescope.
Mauerhan said, “What evolutionary path the star will take is uncertain, but it will definitely not be boring, Nasty 1 could evolve into another Eta Carinae-type system. To make that transformation, the mass-gaining companion star could experience a giant eruption because of some instability related to the acquiring of matter from the newly formed Wolf-Rayet. Or, the Wolf-Rayet could explode as a supernova. A stellar merger is another potential outcome, depending on the orbital evolution of the system. The future could be full of all kinds of exotic possibilities depending on whether it blows up or how long the mass transfer occurs, and how long it lives after the mass transfer ceases.
