Astronomers take the most accurate picture ever of the largest star in the universe

Astronomers have produced the sharpest shot ever of the largest star ever discovered in the universe. These new images indicate that its mass may not be as large as previously thought.

Read also: Mystery The Star Is 570 Billion Times Brighter Than Our Sun Is About To Shine

R136a1 is located in the heart of the Tarantula Nebula, in a cluster of stars in the Magellanic Cloud, near our galaxy, and has been detected since 1985.

In 2010, a team of astronomers ranked it as the most massive ever observed, with a mass of 320 times the mass of the Sun. Recent observations have revised the figure to 250 solar masses.

Stars that are hard to see

This time, a team using the Gemini North and Gemini South telescopes, located in Hawaii and Chile respectively, reduced its mass to between 170 and 230 solar masses, according to a study to be published in The Astrophysical Journal.

“Our results show that the most massive star we currently know is not as massive as we thought.”said Venu Kalari, lead author of the study and an astronomer at US NOIRLab, which operates the Gemini Telescopes.

“This suggests that the upper limit of stellar mass may also be smaller than we thought,” added in a NOIRLab press release issued on Thursday.

40,000 shots

Stars like R136a1, which are the most massive and massive in the universe, are difficult to observe.

First, because their lifespan is very short, counted in a few million years, when the Sun, a more common star, has a life expectancy of ten billion years.

Then because they are generally located in compact star clusters shrouded in stellar dust, which makes it difficult to accurately measure the brightness of their members. However, it is this luminosity in particular that makes it possible to determine the mass of the star.

The NOIRLab team obtained the most accurate image of the stars in the cluster and therefore of R136a1, using a technique called specular interferometry. The Zorro photographer took a very large number of shots, 40,000 in this case, with a very short exposure time, 60 milliseconds. This allowed him to overcome the influence of the Earth’s atmosphere, which disturbed the observations.

The monitoring technology used before has never been used for this kind of thing. This leads the study authors to take their findings with ” to caution “According to Mr. Kalari. While waiting for more efficient instruments, such as the Extremely Large Telescope (ELT), expected in 2027, to improve the measurement.