# Work/Energy to go from surface of moon to mars orbit

1. Mar 9, 2008

### killercatfish

Hello,

This is my first post on this site, but I find that I have gotten myself in to a nice confusion as to where I should go in solving this problem.

I am trying to figure out the amount of energy needed to leave the moons surface and arrive in orbit around mars. Assume all the average values of orbit and radii.

Im finding two main conceptual issues, when (and how mathematically) do I represent gravity from the moon and then gravity from the sun for the voyage over.

Next, if I want to make the "easy" transition into mars orbit, my goal velocity when arriving at mars, is the same velocity as mars' orbit around the sun, i believe. How do i then understand the oribital speed of my object around mars.

I have done some written computations, and its rather confusing, as i would expect. just interested to see if there is anyone on here with any idea to kick me in a direction.

Thanks.