WASHINGTON: A new study has revealed that age of a galaxy can be determined by considering increasing and decreasing brightness some of its stars. When stars reach the end of their life, they start to pulsate and this can help in finding a galaxy’s age, as per a study published in the journal Nature.
Astronomers who conducted the study said they have successfully measured pulses of many stars of a supergiant galaxy Messier 87, which is present about 53,490,000 light years away from earth. According to the astronomers, they used measurements to discover that the galaxy in the constellation Virgo is about 10 billion years old.
While providing details on the study, Dr. Charlie Conroy, a professor from Harvard University and lead author of the study, said there are many ways to find age of a galaxy, but the new study has given a new tool to do that. The tool is important to find age of ancient galaxies like Messier 87.
“The stars in this galaxy probably formed a very long time ago — maybe 10 billion years ago — and if that’s true then this galaxy is a fossil relic from a much earlier time in the universe”, according to Conroy.
The astronomers examined images of the galaxy captured by a telescope in low earth orbit, Hubble Space Telescope, in 2006. They noted that the galaxy’s stars varied after every 270 days. It was happening due to increasing and decreasing brightness of the stars, as per the astronomers.
