The universe’s largest known star has gotten its best close-up yet, revealing that the star may be much smaller than astronomers previously thought.
Astronomers using the Gemini South telescope in Chile captured the image of the star R136a1It lies at its center, about 160,000 light years from Earth Tarantula Nebula into Large Magellanic Cloud — A dwarf companion galaxy of the Milky Way. Their observations suggest that the giant star (and others like it) may not be as massive as previously thought.
“Astronomers still don’t fully understand how the largest stars — stars 100 times the mass of the Sun — form,” he said. statement (opens in new tab) From the National Science Foundation’s (NSF) NOIRLab, which operates the Gemini South telescope. “A particularly challenging part of this puzzle is obtaining observations of these giants, which usually reside in the densely populated hearts of dust-covered star clusters.”
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Gemini South’s Zorro instrument uses a technique known as speckle imaging, which combines thousands of short exposure images of stars. universe cancel the blurring effect Earth’s atmosphere. This technique allowed astronomers to more precisely separate the brightness of R136a1 from its nearby stellar companions, resulting in the sharpest image ever obtained of the giant star.
Previous observations suggested that R136a1 is 250–320 times its mass. they arethe new Zorro observations suggest that the giant star may have a mass between 170 and 230 times that of the sun, making it still the largest known star.
“Our results show us that the largest star we currently know is not as big as we previously thought,” said Venu M. Kalari, lead author of the study and an astronomer at NSF’s NOIRLab. “This suggests that the upper limit of stellar masses may also be smaller than previously thought.”
A the brightness of the star and temperature is based on its mass. In other words, more massive stars appear brighter and hotter. Astronomers estimated the mass of R136a1 by comparing the observed luminosity and temperature with theoretical predictions. Because the new Zorro images more accurately separate R136a1’s luminosity from its nearby stellar companions, astronomers were able to estimate that the star has a lower luminosity and, in turn, a lower mass than previous measurements, according to the statement.
Giant stars like R136a1 grow rapidly, burning through their fuel reserves in only a few million years, leading to a fiery death. supernova explosions, which seed galaxies with heavy elements responsible for the formation of new stars and planets. Such is the fate of most stars with a mass 150 times that of the sun. If stellar masses are smaller than previously thought, then supernovae may also be rarer than expected, the researchers noted.
There was an investigation accepted for publication (opens in new tab) In The Astrophysical Journal.
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