Shallue recruited Andrew Vanderberg, an astrophysicist and doctoral fellow at the University of Texas at Austin, for help on the project, which took about nine months.

Together the pair used 15,000 NASA data points to create a neural network, or artificial intelligence organized in a similar way to neurons in the brain. It learned to recognize small light patterns indicating the existence of an planet that previous automated and manual tests had missed.

AI takes on a new mission: planet hunting. See how we used machine learning to hunt for new planets in @NASAKepler data–and actually found one

To verify that the neural AI was accurate, Vanderberg used it on a set of photos of 670 stars, then compared that to manually sorted results. What took Vanderberg eight hours to complete took the neural network only a few minutes, the astronomer tells CNBC Make It.

Shallue and Vanderberg had taught the system “how to identify planets around faraway stars,” says Shallue in the Google statement.

The two planets Shallue and Vanderberg discovered are “exoplanets,” or planets rotating around sun-like stars other than the one Earth revolves around. Kepler-90i was found to be the eighth planet circling the Kepler-90 star, 2,545 light-years from Earth. The only other solar system known to have eight planets rotating around a sun is our solar system. The other planet identified is Kepler 80g.

2/2 So excited to share 2 newly-discovered planets ID’d by Google AI models: Kepler-80 g, and Kepler-90 i — which is in the first 8-planet system outside our own! Amazing example of how AI can help w/ new scientific discoveries. Next stop, hyperspace:) http://goo.gl/4fuWG2

“We got lots of false positives of planets, but also potentially more real planets,” says Vanderburg, in the NASA statement. “It’s like sifting through rocks to find jewels. If you have a finer sieve, then you will catch more rocks but you might catch more jewels, as well.”

Beyond discovering new planets, this technological development is a step toward discovering alien life, explains Vanderberg to CNBC Make It.

“The main reason we decided to work on this project was to help us measure how common Earth-sized planets in Earth-like orbits around Sun-like stars are,” Vanderberg tells CNBC Make It. He estimates finding alien life could be possible somewhere between 2030 and 2050.

With the discovery of an 8th planet orbiting another star 2,500 light years away, we now have another solar system that ties ours for number of worlds! Learn about the #Kepler90 system:

Both Google CEO Sundar Pichai and Alphabet chairman Eric Schmidt celebrated the 20 percent project on Twitter.

AI can even help astronomers discover new planets – excited to see what they’ll find next! This is huge…

Google isn’t the only company that cultivates innovation with a 20 percent ethos. 3M had a 15 percent time policy going back to the 1990s, Ryan Tate, author of “The 20% Doctrine: How Tinkering, Goofing Off, and Breaking the Rules at Work Drive Success in Business,” points out. Famously, 3M employee Art Fry invented the Post-it via the flex time, according to Wired.

And other top tech companies regularly host hackathons, where employees are encouraged to create solutions to problems under time pressure. The first iteration of Facebook’s Safety feature came out of a hackathon, for example.

As for Google and Shallue, clearly sky’s not even the limit.

See also:

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