Talk:Gravitational parameter

Alternate value of mu

I would like to point out that mu also equals g*r^2. Gravity, g, = G * m₁/r^2. So G = g * r^2 /m₁. Substituting that into mu = GM, we get mu = g*r^2, QED. This is the form of mu that I have been in the habit of using since gravity and radius are usually more available to me than G and m₁. I have done paper missions with less accurate values but they were sufficient for my purposes. See People from Earth to Mars in 30 days - Farred 04:35, 19 February 2013 (UTC)