NASA recently announced the discovery of an eighth planet around a star system called Kepler-90, which now officially ties our own solar system for number of planets. NASA has also discovered a sixth planet orbiting Kepler-80. These discoveries were made using a machine learning system that was “taught” how to recognize the small dips of starlight that might indicate the presence of an exoplanet.
The new Kepler-90i exoplanet is only 30% bigger than Earth and orbits a star 2,545 light years away. It orbits its star once every 14.4 days. Obviously this planet is too close to its host star, and therefore too hot at 435 degrees Celsius (about 800 degrees Fahrenheit), to be able to support “life as we know it”. All eight planets in the Kepler-90 system are closer to their host star than Earth is to our sun.
Andrew Vanderburg described the Kepler 90 system as “a mini version of our solar system. You have small planets inside and big planets outside, but everything is scrunched in much closer.”
Kepler-80g has a similar orbital period of 14.6 days and orbits a star about 1,100 light years from Earth. Kepler-80g is locked in a resonance chain with four other planets in the Kepler-80 system in which the planets’ gravities interact with one another to cause a rhythmic dance in these planets’ orbits. There appears to be little danger of this gravitational dance kicking a planet into the sun, as the resonance chain creates a very stable system.
The discovery of these two planets has resulted in a research paper written by Christopher J. Shallue and Andrew Vanderburg which will be published in The Astronomical Journal. The scientists involved in the discovery of these exoplanets also answered question in a recent Reddit Ask Me Anything event. With the successful discovery of two exoplanets using a machine learning program, scientists intend to feed more data from the Kepler Space Telescope into the same program.