Aquarius is a launch vehicle concept designed for low-cost by Space Systems/Loral to carry small, inexpensive payloads into low earth orbit.

[2] Space Systems/Loral teamed with Microcosm, and Wilson Composite Technologies to study Aquarius under a $110,000 grant awarded by the state of California in April 2001 and delivered a final report in June 2002.

Funding of $1 million was provided in the FY 2004 Defense Appropriations Act to develop a prototype of the low-cost engine for the vehicle.

For the engine development, Space Systems/Loral is partnered with Aerojet, ORBITEC and Microcosm, under the auspices of the Air Force Research Laboratory and was completed in 2006.

[3][4] It confirmed that an ORBITEC engine design with inherently low cost can be scaled up to an intermediate thrust level, from which the next scale-up step to Aquarius should be achievable.