By Theodore Bunker
NASA announced this week that scientists at the Chandra X-ray Observatory have discovered the signs of a planet orbiting a star outside of the Milky Way, which would make it the first planet discovered outside of our galaxy.
The potential exoplanet, which is the name for a planet located outside of our solar system, is located in the Whirlpool Galaxy, also known as Messier 51a.
All other exoplanets that have been discovered were located in the Milky Way, with most of them being within 3,000 light-years of Earth. However, if this potential exoplanet is confirmed, it would be located about 28 million light-years from Earth.
“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,” Rosanne Di Stefano, instructor in astronomy at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts and the study’s leader, said in a statement Monday, the same day the study was published by Nature Astronomy.
“Unfortunately to confirm that we’re seeing a planet we would likely have to wait decades to see another transit,” said Nia Imara of the University of California at Santa Cruz, co-author of the study. “And because of the uncertainties about how long it takes to orbit, we wouldn’t know exactly when to look.”
Another co-author, Princeton University’s Julia Berndtsson, added, “We know we are making an exciting and bold claim, so we expect that other astronomers will look at it very carefully. We think we have a strong argument, and this process is how science works.”
