Messier 87 is around 10 billion years old.
(Mirror Daily, United States) – Astronomers just tracked the galaxy with a heartbeat and thousands of stellar pulses, successfully proving that galaxies vary in light even from millions of light years away. It’s an exceptional discovery that could essentially help scientists determine the age of ancient galaxies.
Researchers and astronomers at the universities of Harvard and Yale decided to investigate if the pulsation of stars could affect the brightness of the galaxy as a whole. Even though they’re just a small part of a bigger picture, perhaps they could make a change. And, even more, it could indicate the age of their entire system of stars as a whole.
Their study was prompted by the fact that while stars reach the end of their life, they begin to undergo certain changes. The brightness shifts, from higher to lower, and their sizes swell up. They become large enough to swallow any planets around them, within a radius that is equal to the distance between Earth and the Sun. These modifications can be noticed.
The starts essentially pulse with light every few hundred days, giving the impression of a heartbeat. Many in our very own Milky Way are in that particular phase of their life.
However, until now, no one has measured if these natural events affect the entire galaxy as a whole. Meaning, if the pulsing light of a dying star could join in with others and essentially show when looking at their entire system from a distance.
The astronomers used NASA/ESA’s Hubble Space Telescope in 2006 to take pictures of the galaxy Messier 87 (M87) over the course of three months. It’s located 53 million light years away from our planet, in the constellation Virgo. All estimations have agreed upon the fact that M87 is also around 10 billion years old, which meant changes were incoming.
Amazingly, the researchers were able to spot a difference, and essentially find a common pulse of the dying stars. Their suggestions were correct. They found that 25%, or 1 in 4 pixels of the images they took varied in brightness. Once every 270 days, the galaxy as a whole essentially featured a heartbeat, due to the multiple dying stars pulsating light. According to Peter Van Dokkum, the initial concept saw galaxies as “steady beacons” in our skies.
However, they are actually “shimmering” because of stars within them that throb.
Even more, astronomers believe that younger galaxies will feature stronger pulses. This means that they could innovate a new way of determine their based on their ‘heartbeat’. It’s like “taking the pulse of the galaxy”, where each one has its own distinctive pattern. Their next goal is to do the same for other galaxies around us.
Even the older galaxies will keep going for a long time though. As Dokkum jokes, it will take them around a trillion years before cardiac arrest.
Image source: mcmahanphoto.com