We may have found a planet in another galaxy for the first time
Scientists may have discovered a planet in another galaxy for the very first time!
The new planet – if it exists – is in the galaxy M51, also known as the Whirlpool Galaxy. That means it’s about 28 million light-years away, which is thousands of times further away than any other planet we’ve ever discovered. Every other planet found so far has been inside our own Milky Way Galaxy.
The researchers behind this discovery used a twist on a common technique for finding planets. Since most exoplanets (planets outside our solar system) are too far away to see, we have to find them in other ways, like looking at the star and measuring its light. This is effective, but not sensitive enough to detect planets in other galaxies. So this time, the scientists used X-rays instead of visible light.
“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 Harvard Smithsonian Center for Astrophysics, the lead author of the new study, which was published in the journal Nature Astronomy.
After searching 238 star systems across three galaxies, the scientists finally found a system with a drop in the X-rays lasting three hours – suggesting this was, in fact, a planet!
It’s estimated to be as big as Saturn, and won’t be observable again for another 70 years. Despite the long wait, this discovery paves the way for amazing new observations in distant galaxies!
Interested in more space stories like this one? Catch a show this weekend in LSC’s Jennifer Chalsty Planetarium, the biggest planetarium in America. Click here to see what’s currently playing.
