From its expansion and acceleration to dark matter and energy, the universe is full of surprises. Recently astronomers have discovered signs of an alien world in a star system outside the Milky Way.
So far, astronomers had only discovered planets that are beyond our solar system but are within the Milky Way. These are known as exoplanets.
However, now researchers found signs of a planet outside of the Milky Way galaxy using NASA’s Chandra X-ray Observatory. If it’s confirmed, it would be the first-ever found in another galaxy.
The potential exoplanet is called M51-ULS-1b. It lies in the spiral galaxy Messier 51 (M51), also known as the Whirlpool galaxy.
Most of the exoplanets found so far are within 3,000 light-years of Earth But this potential exoplanet is about 28 million light-years away.
This discovery relied on the transit method of observing distant exoplanets. The same technique is often used to find exoplanets in the Milky Way. The technique involves watching stars for tiny dips in brightness created by the planets passing in front of them.
To spot this planet, researchers used Chandra to look for dips in the brightness of X-rays. X-rays are generated by small areas on stars. And planets passing in front of those stars could suppress those X-ray emissions. So researchers could see a more obvious transit, which could make farther away things clearer.
Rosane Di Stefano, the Lead Author of the study, said, “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,”
