We’re not alone. At least when it comes to solar systems with the same number of major planets as ours.
NASA today announced details about the recent discovery of an eighth planet circling Kepler-90, a sunlike star that’s 2,545 light years from Earth.
The planet, dubbed Kepler-90i, is a sizzling hot, rocky planet that orbits its star once every 14.4 days, the space agency says. It was found in data from NASA’s Kepler Space Telescope with the aid of machine learning technology from Google.
Computers learned to identify planets by plowing through Kepler’s data and finding subtle variations in light associated with the passage of Kepler-90i across the disk of its parent star.
“Just as we expected, there are exciting discoveries lurking in our archived Kepler data, waiting for the right tool or technology to unearth them,” Paul Hertz, director of NASA’s Astrophysics Division in Washington, D.C., said in a news release. “This finding shows that our data will be a treasure trove available to innovative researchers for years to come.”
Here’s more from NASA:
The discovery came about after researchers Christopher Shallue and Andrew Vanderburg trained a computer to learn how to identify exoplanets in the light readings recorded by Kepler – the minuscule change in brightness captured when a planet passed in front of, or transited, a star. Inspired by the way neurons connect in the human brain, this artificial “neural network” sifted through Kepler data and found weak transit signals from a previously-missed eighth planet orbiting Kepler-90, in the constellation Draco.
While machine learning has previously been used in searches of the Kepler database, this research demonstrates that neural networks are a promising tool in finding some of the weakest signals of distant worlds.
Vanderburg called the Kepler system a miniature version of our own, with smaller planets that are closer in and bigger planets that are farther out. “Everything is scrunched in much closer,” he said.
Don’t hold out hope that scientists — or artificial intelligence — will find life on Kepler-90i anytime soon.
NASA said the planet is about 30 percent larger than Earth, but it’s so close to its star that its average surface temperature is believed to exceed 800 degrees Fahrenheit, on a par with Mercury.