From the back of the book/PDF:
The year is 2268, and humans have settled Mars,
the asteroid belt, and the moon systems of the outer
planets. On Neptune’s moon Triton, a mysterious alien
gate leads to a network of wormholes spanning
hundreds of star systems. But this is a dangerous
time to be alive: crime lords, despotic governments,
and corrupt megacorps are all fighting to control the
future. Choose your friends—and enemies—carefully.
The Mission Guide is the perfect companion for the
Alternity® Science Fiction Roleplaying Game. This
adventure anthology and campaign sourcebook
• An overview of the power groups, villains, and
technology of the Protostar setting.
• A description of the Solar System in the 23rd
• Five ready-to-play adventure episodes set in the
Solar System . . . and beyond.