ch as carbon dioxide, methane, or other ices and gases, the Caltech team said. However, those volatile compounds could not have existed in the hotter zones close to the star.
Finally, the Caltech astronomers discovered that three of the planets have orbits that are related to one another in a very specific way. One planet’s orbital period lasts twice as long as another’s, and the third planet’s lasts three times as long as the latter’s. Planets don’t fall into this kind of arrangement immediately upon forming, Johnson said. Instead, the planets must have started their orbits farther away from the star before moving inward over time and settling into their current configuration.
“You look in detail at the architecture of this very special planetary system, and you’re forced into saying these planets formed farther out and moved in,” Johnson said.
The implications of a galaxy chock full of planets are far-reaching. “It’s really fundamental from an origins standpoint,” said Swift, who notes that because M dwarfs shine mainly in infrared light, the stars are invisible to the naked eye. “Kepler has enabled us to look up at the sky and know that there are more planets out there than stars we can see.”