If you pick up the minefield mission and go to Teenebia(sp?) first (I was exploring, I didn't know I had to go there later.) then you are able to do the second half of this mission (clearing the asteroids, deploying the minefield and defending the minefield) all without ever picking up the scientist. You don't get any credit for doing all that. Once I went back to the outpost and did the first half, I discovered that I had to do the second half over again.
Has anyone else ever noticed this sort of thing with other missions? If you go to a future location, you end up with a later part of your current quests even without going through the first parts?