Well, yeah, sometimes we have that weird feeling that our guts know the answer but we don't know why. Let me show you how I got mine.
Gravitational force obeys an inverse square law - as in the gravitational force depends on the distance asF = GMm/r²
Small m is the mass of astronaut, M the planet, etc. equate the two forces to have the astronaut in equilibrium. G, m cancel, then arrange to get the Mass ratio:Mx / My =140²/581²
