Second Most Earth-Like Planet to Date Found

[Cray]

According to this paper, Kepler 452b has a radius 1.63 times that of Earth (10,396.303 km) and a mass between 3.0 and 7.0 times that of Earth (1.792e+25 to 4.182e+25 kg), giving a bulk density between 3807.431 and 8884.005 kg/m^3 (indicating a solid, rocky planet). At the low end of the mass scale, Kepler 452b has a mean surface gravity of 1.128 g, while at the high end, it is 2.633 g.

Kepler 452, the planet's host star, is 1.037 times as massive as Sol, has a radius 1.11 times that of Sol, and has an effective temperature of 5757 Kelvin; this gives a luminosity 1.216 times Sol's.

Kepler 452b orbits Kepler 452 at a semi-major axis of 1.046 AU, with an orbital eccentricity of 0.03, once every 384.843 days. At this distance, the planet receives 11.128% more insolation than does Earth. With an equilibrium temperature of 260.821 Kelvin (assuming an Earth-like albedo of 0.306) and, if an Earth-like amount of atmospheric radiative forcing is assumed, a mean surface temperature of 294.945 Kelvin, then the planet is eminently habitable and has been for most of its six billion year history.

Such...awesome...crunchy...math...

Radtech, some of that mass range gets into the "lots of internal heat and surface vulcanism ranges." What ranges of density and mass give the most Earth-like surface conditions for a 6-billion year old star and planet?