Have they tried sending a GoPro by itself into space yet? That'd be fun.
I'd wait until the GH5 comes out before making an informed decision between the top options out there right now. Always did find the ergonomics of the Lumix series to be a significant plus against the Sony lineup (much stronger battery life and fantastic handling as both a stills and video camera) - if the GH5 is able to close the image quality gap, I'd say it would stand as a very worthy option to consider.
Gotta wonder which part of the market this is targeting, because I would wager most folks starting out/don't need specialized motorized solutions will be more than happy to take one of the many ~$100 slider options that are already out there.
Passed along - one of the best visualizations on this I've seen to date.