Regardless of whether or not it was a mistake it peeves me off too. Either way they were saddling NASA with another failed Mars probe that they don't deserve the (dis)credit for. It wouldn't surprise me if it were intentional though, they even went to the trouble of making it look like a MER rover. I wonder how many people who saw that movie now think that NASA really was responsible for the real life Beagle 2 failure? The mistake in the teaser trailer of Beagle 2 depicted as a MER rover driving around a blue-skied Mars made me laugh, and I was kinda hoping they'd fix it for the movie or just cut the scene (yeah, unrealistic expectation, I know). Not only did they not fix or cut it, they made the blunder so large that the whole rover mistake seems like a nit-pick by comparison.