One of the annoying things about the Doctor was that he often ducked questions whose answers were too complicated or too difficult to manage. The ships however, there was some thing he saw no reason not to explore further.

"It might be real but amazingly difficult to find... Or a story like you've said. I suppose we won't know that until we start looking for it.

There. That looks like an old Mars lander. I haven't seen one of those since, well, it has been a while."