Sea Star MSLV

IOS' Neptune will support a number of human spaceflight and other pay-load launch missions. In November 2004, IOS entered as a competitor for America's Space Prize, the $50-million contest sponsored by Bigelow Aerospace for a privately developed launch of a piloted vehicle to orbit.

Neptune will be powered by two high-thrust bipropellant liquid rocket engines. Like Sea Star, Neptune is designed to launch from the sea using a two-stage booster and an orbital stage. Its first two booster stages will each use a single hypergolic engine, burning WFNA and HX, with four steering rockets per stage. The orbital stage will use a single cryogenic LOX/HX engine. The booster stages are designed to be water-recov-erable with a parachute landing and reusable.

The orbital stage and crew capsule will allow for stays on orbit of up to 7 days. Fuel tanks of the orbital stage can be outfitted for habitation and may even serve as future modules for an orbiting space hotel. The crew capsule can be reused after a parachute landing. The crew compartment includes an aft escape and service module to pull passengers away from the vehicle and to a safe landing in the event of vehicle failure.