It is the year 2016, in America. For the last several years, strange artifacts have falling from space. Some are devastating weapons, others create weird unexplainable effects. Nobody knows exactly where they come from, but the consensus is that they are alien in origin.
No signs of alien biology have been discovered, but these artifacts have a mostly consistent energy signature and design patterns.
The game is set in a modern metropolis somewhere in the United States. The players are superheroes whose powers may be influenced or caused by interaction with the alien artifacts.