Kepler-22b is a super-Earth that could be covered in a super ocean. The jury is still out on Kepler-22b’s true nature; at 2.4 times Earth’s radius, it might even be gaseous. But theoretically an ocean world tipped on its side – a bit like our solar system’s ice giant, Uranus – turns out to be comfortably habitable based on recent computer modeling. Researchers found that an exoplanet in Earth’s size range, at a comparable distance from its sun and covered in water, could have an average surface temperature of about 60 degrees Fahrenheit (15.5 Celsius). Because of its radical tilt, its north and south poles would be alternately bathed in sunlight and darkness, for half a year each, as the planet circled its star.

PLANET TYPE
Super Earth
DISCOVERY DATE
2011
MASS
9.1 Earths
PLANET RADIUS
2.1 x Earth
ORBITAL RADIUS
0.812 AU
ORBITAL PERIOD
289.9 days
ECCENTRICITY
< 0.72
DETECTION METHOD