I'm currently in a PBeM game with a bunch of randos. Its going well but slooow. 3 of us are good at getting our turns in quickly but there's always one. Sometimes takes him 3-4 days....
It's IGO-UGO but in phases. Each turn is a year. First, in reverse initiative order, each player builds and pays for launch vehicles, crewed vehicles, robotic explorers, and raw materials they want to ship to space.
Second, in reverse initiative order (although high initiative players an jump the queue), each player launches payloads and moves vehicles already in space (and rolls for catastrophic failures for vehicles that use their engines. Vehicles relying on inertia just kind of glide along).
Third, in initiative order, players explore celestial bodies and, if successful, possibly discover anomalies and search for life. They also check for malfunctions and crew endurance.
Fourth, build and/or expand bases.
Later in the game, there is also trading, mining, and combat but it takes a while to reach that stage.
At the start of each new decade, players develop (and steal) new technologies, get funding for the next decade, enact new political policies, and spend political capital on diplomacy and bidding for initiative.
That's basically it.
I think the rules are available from Compass Games's web page. There are also a lot of good 2-3 page summaries on BGG as well as in the VASSAL module.
