G is the gravitational constant
M is the mass of the planet
m is the mass of the object being weighed
r is the radius of the planet / distance between the centers of mass of two objects

The equation shows that gravity scales linearly with mass, and scales inversely with the square of distance. The article says K2-18 b is 8.6 times Earth's mass, and 2.6 times Earth's radius. So the weight of a 100 kg mass would be:

F = 100 × 8.6 / (2.6)²

which works out to a weight of about 127 kg, or 1.27 times heavier.

[–] The_Che_Banana@beehaw.org 2 points 2 months ago

Neat! Thanks!

[–] eestileib@sh.itjust.works 0 points 2 months ago

I read this as "weeb discovers..." and was a little disappointed.