1. The problem statement, all variables and given/known data A projectile is fired straight away from the moon from a base on the far side of the moon, away from the earth. What is the projectile's escape speed from the earth-moon system? m_earth= 5.97x10^24kg m_moon= 7.348x10^22kg radius_earth= 6.371x10^6m 2. Relevant equations V_esc=√(2GM/R) KE=.5mv^2 PE=mgh 3. The attempt at a solution My thought was that you would use the escape velocity equation and take into account the mass of both the earth and moon, and for the radius, sum the radius of Earth, the distance between the earth and moon, and the diameter of the moon. That wasn't right. I then considered the kinetic energy required to escape both systems separately, and then went to sum those and solve for the velocity using KE=.5mv^2, but without a mass for the body that won't work. I also know that escape velocity isn't dependent on mass of the object escaping, so I also disregarded this method.