Scientists reveal the largest star in the universe
The star called R136a1 is considered the largest and most massive star discovered in terms of mass, as its mass is estimated at 265 to 355 times the mass of the Sun, and it is 163 thousand light-years away from us in the Large Magellanic Cloud galaxy.
Note that this star is classified as a super blue star. Its surface temperature is 53 thousand Kelvin and it is located in the direction of the Swordfish constellation.
Astronomers said that the largest star ever observed in the universe is not as large as previously estimated, based on what new observations have shown that indicate that this applies to other large stars.
The star "R136a1" (R136a1) is located in the Tarantula Nebula, within a group of stars in what is known as the Magellanic Cloud, near the Milky Way Galaxy, which includes Earth. Its discovery dates back to 1985. In 2010, a team of astronomers classified it as the largest star. The largest size ever observed so far.
Scientists believed that the mass of the star was 320 times greater than the size of the sun, but previous modern observations forced these estimates to be modified, as they showed that its size is only 250 times larger than the sun.
As for the most recent study, which will be published in the Astrophysical Journal, which specializes in astrophysics, a team using the North Gemini telescopes in Hawaii and the South Gemini telescopes in Chile reduced the estimate of its mass to between 170 and 230 solar masses.
“Our results show that the most massive star we currently know is not as massive as we thought,” said the study’s lead author, an astronomer at the American NOIRLab center that runs the Gemini and Fenno-Callari telescopes.
He added in a statement issued by the center on Thursday, “This indicates that the upper limit of stellar mass may also be smaller than we thought.”
The largest and brightest stars in the universe, such as R136A1, are difficult to detect.
This is due, firstly, to the fact that its life span is relatively very short, as it is limited to a few million years, while the life expectancy of the Sun is ten billion years.
The second reason is that they are generally located within compact star clusters surrounded by stellar dust, which makes it difficult to accurately measure their brightness, knowing that this brightness is precisely what allows determining the mass of the star.
The Noir Lab team obtained the most accurate image of the stars in the group and therefore of the star R136A1 using a technique called speckle interferometry.
The center's "Zorro" imaging device captured a very large number of images, amounting to 40,000, with a very short exposure time, which enabled it to avoid interference by the Earth's atmosphere in the shots.
Given that the observation technology used has not previously been applied to this type of target, the study’s authors treat its results “with caution,” according to Kalari, while waiting for more efficient tools to improve the measurement, such as the Extremely Large Telescope (ELT), which is expected to enter service in a year. 2027.
Source: websites