The Apollo Eleven
"All I see is they were once human, dammit -- they were once as human as your or me, and now --"
Originally a team of human astronauts sent to the moon to establish an international station, Earth's first moon base. Instead, while moon-side, they made contact with extraterrestrials who transformed their physiologies and retrained them as emissaries to represent them on Earth. The Apollo Eleven became wanted criminals after escaping from a Federal Research Facility and operated while on the run from the law from 1972-1974.
In 1972, were part of a celestial convergence with an Omni-Brain. They were also a part of the group of heroes defending Astro City during Madame Majestrix's Invasion during the Spring of 1973. In 1976 they saved Australia from the Golden Horde.
The Apollo Eleven had been charged a task by an alien collective known as the Continuum: to guide and prepare humanity to join the wider community of extraterrestrial civilizations. The Continuum communicated with the ex-astronauts via their agent, the cosmic being called Xosmos. They group can also call upon The Incarnate, a near omnipotent being formed when the Apollo Eleven come together as one individual energy force.
LGM, is an actual alien entity and not a member of the ten-person moon group. He was placed on the team as an observer for Xosmos and the Continuum.
In 1982, the crime organization Pyramid captured them in an attempt to harness and use the powers of the Incarnate. Pyramid's abortive attempt unleashed a destructive personality called Kerresh the Devastator. In the aftermath of an intense battle, the group lost their powers and were returned to human form. L.G.M.'s fate remains unknown.
All members of the Apollo Eleven have been shown in flight. Whether this is a power within each of them or some members are being levitated by the powers of others is unknown.
Kahoutek and Aquarina are a couple. As are Arthro and Gas Giant, though their relationship is complicated by the latter's incorporeal state.
Kurt Busiek considered "Saturn Five" as an alternate name for the group, as it would require fewer members, but Alex Ross convinced him that "Apollo Eleven" was more specifically tied to the time period.
Physically, the members of the team seem to be based either on different popular conceptions of what aliens look like (Greys, little green men, etc.) or on cosmological phenomena (black holes, comets, etc.) Kahoutek's name is a reference to the real-life Comet Kohoutek (spelled with an o as the first vowel).