Mission Timing?

By KAGE13, in Merchant of Venus

When are missions completed?

Our first game, I completed a mission and pulled a new one that I figured I "auto" completed because I was already on the planet and had what I needed.

Then I pulled another mission where it said to pay for your level 3 pilot. Either I can never complete that mission or I "auto" get that one as well.

Do I pull a new mission if I can't complete one?

Can I just keep completing as many missions as I want in a single turn? I potentially could have completed 3 or more missions in 1 turn.