A lot of people (cough cough nutters cough cough) point to the terrible ratio of successful to unsuccessful Mars missions and claim that NASA (and evidently the European Space Agency, which they forget about) is covering up something.
I don't think anything is covered up. But what's not getting out is how hard it is to get to Mars. The problem is that Mars has planetary gravity, so touching down means lots of thrust to slow the probe, but it also has air, and just enough to make that difficult as well. NASA has actually done pretty well getting things down to the surface (when dumb engineering mistakes don't interfere), despite the difficulty.
But as payloads increase, things get harder. And we're now talking about landing people there. That's not just hard; it turns out that we really aren't sure how to do it at all.
So says Rob Manning, the Chief Engineer for the Mars Exploration Directorate, and you can read more about this fascinating topic at Universe Today, in an article written by Nancy Atkinson. It's worth reading about current plans, future notions, and all the pains taken just to set down on the Red Planet. You may be surprised. And if you're a conspiracy theorist, you may just learn something.
Well, probably not. But now we have someplace to link to when CTers rave about NASA and Mars.