# Earth->Mars: Porkchop, departure burn and orbit inclination

My goal is to get a graph "spaceport latitude"<>"delta-v to reach mars".

Using "Trajectory Optimization Tool" (Matlab one) I have successfully generated porkchop graph for Earth->Mars transfer. It does not take into account orbital parameters around Earth i.e. it is the trajectory we are going to use regardless of space port location. Is that correct to assume that spaceport latitude would not affect optimal Earth->Mars trajectory?

To get to this specific trajectory, I do departure burn calculation in the same tool for initial circular 200km LEO with different inclinations of the orbit.

I found that lowest delta-v is needed to depart from 21° orbit inclination, although I assume achieving this orbit will require more energy than 0° one from equator.

My further thinking is that I need to record delta-v requirements for all orbital inclinations, calculate all possible delta-v's for all spaceport latitudes to reach initial orbit with all inclinations, try all orbital plane changes on LEO and by combining all this (i.e. finding optimal combinations of initial inclination and plane change for each spaceport location) with delta-v I got for departure burn to Mars for all inclinations I might get the graph I want.

Is there a more straightforward way of doing so? Maybe there was already some research done on this topic which I am overlooking?

• Wow! Does the optimization include low-energy transfers and ballistic capture? – uhoh May 9 '16 at 3:28
• @uhoh As far as I understand it calculates only for 1 burn departure. With regards to delta-v/C3 1 burn is more efficient than low-energy transfer. So different program would be needed for that. With regards to capture, program allows you to set a specific maximum velocity on arrival. – BarsMonster May 9 '16 at 3:32
• Looks like the 2018 opportunity. – Mark Adler May 9 '16 at 5:55
• @uhoh If this is the same tool, then it is just a Lambert solver using patched conics. – fibonatic May 9 '16 at 11:55
• @fibonatic Yes, this is the one. – BarsMonster May 9 '16 at 16:35

For the selected the departure conditions, the parking orbit velocity and radius can be used to easily compute the $\Delta V$ from that orbit to the departure C3.