Kepler-85 b: 1.8 Earth Masses
Super-earth around Kepler-85
It is 1.78 times Earth's radius, closest in size to Earth, and 1.8 times Earth's mass, at 1.82 g/cm3, less dense than Earth. A year there lasts 8.30 days. The host star Kepler-85 runs at 5505 K with 0.93 times the Sun's mass.
Radius
1.78 Earth radii
Mass
1.8 Earth masses
One year
8.30 days
Host star
Kepler-85 at 5505 K
Distance
2495 light-years
Starlight blocked
0.035% at each transit
The state of the record for this planet
A measured radius. Yes.
A mass. Yes.
A density, the one clue to composition. Yes.
A semi-major axis. No.
A measured temperature rather than a derived one. No.
An eccentricity, so the orbit shape is known. Yes.
What you get from the shadow
How deep the star dims fixes the planet's size relative to it.
Two independent measurements sit behind this page: a dip in starlight for the size, and something else entirely for the mass. Together they make a density.
Kepler-85 has 4 known planets. A crowded system is worth more than the sum of its planets: the timing of each transit constrains the others.
Found by Kepler in 2012. Kepler stared at one patch of sky for four years, which is why so many of its planets have short periods: a planet only counts once you have seen it cross several times.
