[SpookyZalost]

wanted to post some new interesting information here.

so everyone's heard about all those exoplanets they keep finding, the so called "super earth's" I'm sure when looking at the 2 to 8 earth masses you probably think... nah we can't go there, that's 2x to 8x earth gravity.

well that's partially right...

see the equation for surface gravity is the mass divided by the radius Squared.

g = G * M / r^2

let's apply that equation to the closest exoplanet, proxima centauri B.

mass: 1.27

Approximate Radius: 1.1

g = G * 1.27 / 1.1^2

first you convert those numbers to metric.

Earth:

Mass: 5.98 * 1024kg

Radius: 6378 km

Proxima Centauri B:

Mass: 7586472000000000kg

Approximate Radius: 7008.1km

so the surface gravity is
0.0000000103089776 m/s^2

or just under 1 G

Earth's surface gravity is

0.0000000010495868 m/s^2

so while the planet is bigger, and more massive it's surface gravity is lower.

keep that in mind next time you hear about an exoplanet, because you may weigh less not more than you do here on earth... and even if it is higher, it might not be by as much as you think Density play's a key role here, the less dense, the greater the surface area and thus the lower the surface gravity.