Kepler shows small exoplanets are either super-Earths or mini-Neptunes
Tally from the prolific space telescope adds 10 more potentially habitable rocky planets to count
PLANETARY COUSINS Planets may be lumped into two groups: smaller and rocky like Kepler-452b (left), or bigger and gassy like Kepler-22b (right).
W. Stenzel/NASA Ames