Astronomers used images from two Hawaii Island telescopes to identify a rare blue supergiant star.
Researcher Youichi Ohyama, of the Institute of Astronomy and Astrophysics, Academia Sinica in Taiwan, said the star, found in the constellation Virgo, beyond the Milky Way Galaxy, would have emerged more than 55 million years ago in a “wild” environment.
“If our interpretations are correct, this is possibly the farthest star ever discovered with spectroscopic observation,” Ohyama said. “It shows the huge potential for stellar spectroscopy with extremely large telescopes, e.g., the Thirty-Meter Telescope, being planned for the future.”
Suzanne Frayser, spokeswoman for Subaru Telescope, described the discovery as a “rare thing and a rather dramatic context.”
Even more exciting, she said, is that the discovery “may change our ideas of how stars are formed.”
Subaru officials described blue supergiants as extremely large, bright, hot stars that are 10 times larger than our sun. Less than one in 10,000 stars is a blue supergiant.
Officials described the environment in which the star emerged as “within the long trail of gas stripped from a galaxy (IC 3418) as it sped rapidly into the Virgo cluster and interacted with the hot plasma of the surrounding intercluster medium.”
Ohyama and other researchers used the Subaru Telescope’s Faint Object Camera and Spectrograph, the Canada-France-Hawaii Telescope, and the NASA Galaxy Evolution Explorer to see “unprecedented views of the star formation process in this intergalactic context and showed the promise of future investigations of a possibly new mode of star formation, unlike what occurs in our Milky Way Galaxy,” Subaru officials said.
Another researcher on the project, Ananda Hota, said the exotic system is important for astronomers.
“Precisely because the thermal and dynamic contrast to typical star formation that our research shows cannot be observed within our Milky Way, the details revealed by the Subaru Telescope’s spectroscopy and the deep, sharp imaging of Canada-France-Hawaii Telescope are opening up a new avenue for investigating the baffling fundamentals of star formation,” Hota said.