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New Large Rocky Planet Found
An anonymous reader writes "Discovery News is reporting the discovery of a super-sized rocky planet orbiting a red-dwarf. The star is located about 9000 ly from the sun. The planet consists of rock and ice and orbits at around the distance of asteroid belt. The planet could not grow to Jupiter size because the star is small and the system ran out of gas. The planet is about 13 earth masses and was discovered using the microlensing technique. Since most of the stars in the Milky Way are smaller than the sun, we should expect more of similar findings."
Go back to your high school physics, g is proportional to the mass and the inverse of the distance squared. Assuming a sphere, mass equals density x 4/3 x pi x R^3. Apply the inverse R^2 term and you end up with g proportional to density x R.
The planet might be 13 times the mass but if the density is the same as Earth then g is only 2.35 times that of Earth (cube root of 13).
ZombieEngineer