Clever idea! And there's some story behind it, that's nice. And visually great too, I only think the flashing light on the rover itself wasn't necessary... actually the rover whole would be made much better (visually).
I miss some objects according to which I can orient in the world.
And I am pretty sure that the delay is more than 2.5 sec! It's around 4 sec which is way too much.
But it's really a good game, nice work.