The United Planetary Space Fleet, or Fleet for short, is the military body formed out of the remnant of the UN Peacekeeping Force of the late 20c. It is a military force the reports directly to the Admiralty on Earth and JHQ (Joint Headquarters), which is located aboard the Daedalus Space Station.

Fleet is the military space arm of the United Nations (UN) alliance of member countries committed to fulfilling the goals of the Walsingham Treaty, signed on March 12th, 2112. In accordance with the Treaty, the fundamental role of UPSF is to safeguard the freedom and security of its member countries, their co-dependents and commercial interests, by political and military means, in space.