Google's research team Google AI has applied machine learning [nasa.gov] to data from NASA's Kepler [wikipedia.org] space observatory, finding an 8th exoplanet orbiting Kepler-90 [wikipedia.org] (2,545 ly away). The team also found a sixth exoplanet orbiting Kepler-80 [wikipedia.org] (1,100 ly away):
Our solar system now is tied for most number of planets around a single star, with the recent discovery of an eighth planet circling Kepler-90, a Sun-like star 2,545 light years from Earth. The planet was discovered in data from NASA's Kepler Space Telescope.
The newly-discovered Kepler-90i – a sizzling hot, rocky planet that orbits its star once every 14.4 days – was found using machine learning from Google. Machine learning is an approach to artificial intelligence in which computers "learn." In this case, computers learned to identify planets by finding in Kepler data instances where the telescope recorded signals from planets beyond our solar system, known as exoplanets.
[...] Kepler-90i wasn't the only jewel this neural network sifted out. In the Kepler-80 system, they found a sixth planet. This one, the Earth-sized Kepler-80g, and four of its neighboring planets form what is called a resonant chain – where planets are locked by their mutual gravity in a rhythmic orbital dance. The result is an extremely stable system, similar to the seven planets in the TRAPPIST-1 system [nasa.gov].
Their research paper [harvard.edu] reporting these findings has been accepted for publication in The Astronomical Journal. [Christopher] Shallue and [Andrew] Vanderburg plan to apply their neural network to Kepler's full set of more than 150,000 stars.
The size of Kepler-90i is estimated at 1.32 ± 0.21 Earth radii. Surface temperature is estimated at 435°C (709 K).
Kepler-80g is likely smaller at 1.13 ± 0.14 Earth radii, with a cooler surface temperature of 144°C (418 K).
The outermost known exoplanet in the Kepler-90 system, Kepler-90h [wikipedia.org], has a mass under 1.2 Jupiter masses and a temperature of around 292 K (19 °C; 66 °F), so it may be a good candidate for hosting life on a moon.
NASA will host a Reddit AMA [reddit.com] at 3 PM EST to discuss the findings.
Related: Seven Earth-Sized Exoplanets, Including Three Potentially Habitable, Identified Around TRAPPIST-1 [soylentnews.org]
Previously: Google and NASA to Reveal Mysterious New Space Find [soylentnews.org]