I was going to say build a space plane that can land on the mun.It can be multi-stage. You could do most accurate sputnik recreation. Build it to look like the real thing, then put it into orbit. Or my personal favorite, Launch a rocket into orbit and try to land it back at the space center.Closest proximity to the launch pad wins. Rule 1. Must be a 130,000 Km orbit Rule 2. The spot where your craft touches the ground is where it counts. Rule 3. Crew must survive. If you end up using this one, and I see the video. I will make a special flag for the winner. If you could just please message me in advance.