Can I get definition of "Rover" that you'll work with?

I'm assuming it is something like "The space agency that launches it calls it a 'rover'." or perhaps "It was designed for surface travel capabilities and has a mission that largely involves use of such capbilities."

You woudln't, for instance, count an orbiting space-ship, nor a lander that is incapable (or only minimally capable) of surface ground travel as a rover?

@MatthewLeong I would not count an orbiting space-ship. but a lander that is capable of moving a small distance would count

@AmmonLam - with wheels/treads or other land-based motion?
i.e. if a lander had some gliding or re-launching (to leave the planet) capabilities (but no wheels/treads/etc, that wouldn't count as a rover?

@MatthewLeong
rover: a vehicle for driving over rough terrain, especially one driven by remote control over extraterrestrial terrain.

I think I would count a gliding rover. If the machine can only launch on mars and relaunch to leave the planet that wouldn't count

@AmmonLam - Sorry to keep bugging you, but I aim to be able to answer your question as best as I can.

What about a helicopter designed for very short-range tasks?
For instance, imagine that NASA put a lander/launcher on Mars meant to retrieve samples from the current rover (Perseverence).

Suppose that Perseverence is hoped to be able to be able to deliver the samples to the lander/launcher (perhaps with a claw or some-such).

However, as insurance, the lander/launcher has some little helicotpers designed to be able to snatch things out of Perseverence's inventory, so that they can be loaded up and launched off Mars.

Those helicopters are surely not 'rovers', right?
To me it would seem a mischaractisation to consider such a mission as a 'rover landing on mars', and I imagine that you agree but I wnat to make sure.

@MatthewLeong You have put a lot of thought into this question.

I'll resolve this question according to the criteria you decided. If you would like, you can type out a criteria for resolving in this comment.

Or even better, given the effort you've put in, you could create a new market and I can direct traders of this market to your market with a more clearly defined resolution criteria

@AmmonLam I have a vested interest due to having bet already, so I don't think it would be fair for me to tell you how to resolve it.

I think I've given my opinion on what counts as a rover, and if you agree then so be it.

I may have given the illusion that I've thought about this a lot, but my example was merely my rushed understanding of NASA's next planned Mars mission from died reading NASA's website. (I might have misunderstood it since I did hurry to buy in order to get a better price.)

@MatthewLeong I think you creating a new market would be good. you can lay out the resolving criteria and it would be fair for others to bet according to the laid out resolving criteria.