In Artemis program SpaceX Starship is going to be used as Human Landing System (HLS), landing on the Moon with Artemis astronauts. When launched from land, Starship doesn't have enough propellant to get to Moon orbit, let alone Moon surface. To solve this problem, Starship will have to be refueled in orbit.
On Starship 3rd flight SpaceX plans to demonstrate propellant transfer within one spacecraft. So far there have been no announcement of the first attempt of propellant transfer between two ships.
For this market to resolve positively, the following should happen:
One Starship has to be launched and reach orbit.
The second Starship has to be launched while the first Starship is still in orbit.
It has to be announced either ahead of time or after the fact that propellant transfer is planned or has been attempted.
The attempt doesn't have to be successful. It will count even if the second Starship fails to reach orbit.
If the market gets popular and the timeframe proves to be too short, I'll add extra options.
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I do not bet on my own questions.