Why DayTrippers Has No Setting
You may have noticed that DayTrippers has no Setting and no Timeline, only a handful of important companies and a list of optional Tech Advances for the GM to choose from. Admittedly, this is an unusual approach to the exposition of a campaign world.
It is typical for Players to expect something like "The History and Atlas of the Home World", but I refuse to write such a thing. I paint DT's Home-Earth only ironically, and with the slightest touch of the brush. Why? Several reasons...
First, it's not really that important in any given session; PCs don't spend a lot of detailed time on Home-Earth. All the adventure happens out there.
Second, it would force me to make predictions about technology and politics that I don't want to make for you as a GM, especially given that some GMs may want to instill their own personal politics, or use future histories written by SF authors as the backgrounds of their own campaigns. I wouldn't want to be "wrong" (like I was in 1988's "CyberSpace", when I predicted that the Cold War would last into the 2050s). Better to be suggestive and optional than literally wrong.
Third, DT is really about episodes, even though they may be strung together as campaigns. But most of the "color" is intended to occur "out there" in intraspace, not on Earth. The color comes in the adventure modules themselves, as well as the Nodes you create on your own, and your multiverse will be the gestalt of all the modules and Nodes you've chosen to include or create.
Ultimately (and related to the above): My Home-Earth is not your Home Earth. I refuse to say "The Mars Colony is an important part of interplanetary trade in 2116", because you might want the Mars Colony to be that, or you might want it to be a barely-functional installation with technical problems for the PCs to solve, or an uncharted expanse of potential build sites for the PCs to survey, or a small struggling base camp where soldiers are at war against a hostile planet, etc. Depends what sort of science fiction you and your Players are into.
DayTrippers wants to empower your creativity, not mandate mine.