New Delhi | Jagran News Desk: Astronomers have now detected a planet transiting a star outside of the Milky Way galaxy. The unique discovery was led by Nasa’s Chandra X-ray Observatory that has peaked into the spiral galaxy Messier 51 (M51), also called the Whirlpool Galaxy.

According to Nasa, the Astronomers over the years have detected over 4,000 such exoplanets, some Earth-like, some hot Jupiters, and others decaying due to astronomical events in their region. Exoplanets are defined as planets outside of our Solar System.

“We are trying to open up a whole new arena for finding other worlds by searching for planet candidates at X-ray wavelengths, a strategy that makes it possible to discover them in other galaxies,” said Rosanne Di Stefano of the Center for Astrophysics | Harvard & Smithsonian (CfA) in Cambridge, Massachusetts, who led the study, which was published today in Nature Astronomy.

To detect the newest candidate, astronomers studied X-rays. Since the region producing bright X-rays is small, a planet passing in front of it could block most or all of the X-rays, making the transit easier to spot because the X-rays can completely disappear. The team used it to detect exoplanet candidates in a binary system called M51-ULS-1, located in M51.

The team used this method to detect the exoplanet candidate in a binary system called M51-ULS-1, located in M51. This binary system contains a black hole or neutron star orbiting a companion star with a mass about 20 times that of the Sun. The X-ray transit they found using Chandra data lasted about three hours, during which the X-ray emission decreased to zero. Based on this and other information, the researchers estimate the exoplanet candidate in M51-ULS-1 would be roughly the size of Saturn, and orbit the neutron star or black hole at about twice the distance of Saturn from the Sun, revealed Nasa.

“Unfortunately to confirm that we’re seeing a planet we would likely have to wait decades to see another transit,” said co-author Nia Imara of the University of California at Santa Cruz. “And because of the uncertainties about how long it takes to orbit, we wouldn't know exactly when to look.”

As per the Astronomers, if a planet actually exists in this massive system it likely had a tumultuous history and violent past since it would have had to survive a supernova explosion that created the neutron star or black hole. They further speculate that at some point the companion star could also explode as a supernova and blast the planet once again with extremely high levels of radiation.

Posted By: Ashita Singh