A planet has been detected outside of Earth’s Milky Way galaxy for the first time.
Astronomers have spotted the planet, which may be the size of Saturn, some 28 million light years away.
The planet of M51, a spiral galaxy also known as the Whirlpool galaxy, is said to be the first “extraplanet” to be detected.
An “extraplanet” lies outside our home galaxy.
It is thousands of times farther away than the 4,000 “exoplanets” – those that orbit a star outside the Earth’s solar system – that have been discovered in the Milky Way.
Researchers using NASA’s Chandra X-ray Observatory believe that an x-ray attenuation in the system they were observing was caused by a planet passing in front of the collapsed core of a supergiant star or black hole.
“We know we are making an exciting and bold claim, so we expect other astronomers to examine it very carefully,” said Julia Berndtsson of Princeton University in the United States, co-author of the research published in Nature astronomy.
“We think we have a strong case, and this process is how science works. “
The research paper details their research for X-ray transits in three galaxies beyond the Milky Way, using both Chandra and the European Space Agency’s XMM-Newton. Searching for over 200 systems resulted in only one successful discovery.
The research could open a new window to search for “extraplanets”.
“We are trying to open up a whole new arena to find other worlds by looking for candidate planets at x-ray wavelengths, a strategy that allows them to be discovered in other galaxies,” said Rosanne Di Stefano of the Center for Astrophysics, Harvard and Smithsonian (CfA) in Cambridge, Massachusetts, who led the study.
Update: October 26, 2021 9:01 am