AI finds solar system with 8 planets like ours
MIAMI: A solar system like ours, with eight planets, has been discovered with the help of a Kepler Space Telescope and artificial intelligence from the National Aeronautics and Space Administration (Nasa), the United States space agency said on Thursday.
“Our solar system now is tied for most number of planets around a single star,” Nasa said in a statement. But, none of the planets are expected to be hospitable to life.
The eight-planet system, the largest known outside of ours, orbits a star called Kepler-90 some 2,545 light years away.
“The Kepler-90 star system is like a mini version of our solar system,” said Andrew Vanderburg, an astronomer at University of Texas at Austin.
“You have small planets inside and big planets outside, but everything is scrunched in much closer.”
A newly-identified planet, Kepler-90i, is a rocky planet like Earth, but orbits its star once every 14.4 days, meaning a full year there is the same as two weeks on Earth.
“Kepler-90i is not a place I would like to go visit, though. Its surface is likely far too hot,” said Vanderburg.
Nasa calculated its average temperature about 426°C, as hot as Mercury, the closest planet to the Sun.
Scientists found it by using machine learning from Google.
The process involved teaching a computer to scan a trove of 35,000 possible planetary signals collected from Nasa’s Kepler Space Telescope to search for signs of planetary transits.
Transits are the dimming of light when planets pass in front of a star.
The Kepler Space Telescope was launched in 2009 and had scanned some 150,000 stars.
Astronomers have confirmed the existence of some 2,500 faraway worlds using Kepler data.
“I became interested in applying neural networks to astronomy when I learnt that the Kepler mission had collected so much data that it was impossible for scientists to examine it all manually,” said Christopher Shallue, a senior software engineer with Google’s research team.
“Instead, scientists selected the strongest signals, which are the most likely to be actual planets, to receive the most attention.”
Shallue likened this process to “looking for a needle in a haystack”.
More planets are expected to be found because researchers plan to apply their neural network to Kepler’s full set of more than 150,000 stars.
“There is a lot of unexplored real estate in the Kepler-90 system,” said Vanderburg.
“It would be surprising to me if there were not any more planets in around that star.”
One day, artificial intelligence might be used to search specifically for more Earth-like planets, which have proven difficult to pin down.
“For the first time since our solar system planets were discovered thousands of years ago, we know for sure that the solar system is not the sole record holder for the most planets, and we have just scratched the surface,” Vanderburg said.
“There may be systems out there with so many planets that they make our eight-planet solar system seem ordinary.”
The findings are published in The Astronomical Journal. AFP