NASA 1999 SBIR Phase I


PROPOSAL NUMBER 99-1 24.01-0890 (Chron: 991580 )


Mars Gas Hopper


The Mars Gas Hopper, or "gashopper," is a novel concept for propulsion of a robust Mars surface hopper vehicle which utilizes indigenous CO2 propellant to provide Mars exploration with greatly enhanced mobility. The gashopper will first retrieve CO2 gas from the local Martian environment, compressing it with a pump to store it in liquid form at a pressure of about 10 bar. When enough CO2 is stored to make a substantial ballistic trajectory hop to another Mars site location of interest, the CO2 propellant will then be moderately heated to form a very high pressure supercritical gas which is then expanded through a simple rocket thruster system. An alternative gashopper concept uses liquified CO2 which is passed through a heated particle bed heat exchanger which heats and gasifies the CO2 for propulsion. The gashopper shall use its CO2 propulsion system for major liftoff, attitude control, and landing propulsive burn(s), as required. Unlike chemical rocket propellants, the gashopper's CO2 propulsion system will not contaminate the landing site with organic molecules or water. Thus, this Mars surface exploration system is uniquely appropriate for astrobiological research. Inthis study, Pioneer Astronautics proposes to demonstrate the feasibility of the gashopper concept.


the gashopper concept is primarily designed to enable greatly enhanced mobility for robotic Mars exploration vehicles. However the gashopper CO2 rocket system (CRS) has many potential important commercial applications for application in the space. Currently there is a spectacular boom in the commercial satellite market supporting global communications. Small CRS thrusters could be used for stationkeeping and reaction control system (RCS) propulsion for satellites. Currently the propellant of choice for such applications is monopropellant hydrazine, which is toxic, dangerous, expensive, and offers a rather low performance (Isp=220 s). CRS based propulsion systems will be much cheaper, safer, and easier to integrate than hydrazine, and while offering comparable specific impulse performance. There likely could be a substantial reduction in launch system processing servicing cost for a CRS when compared to a state-of-the-art hydrazine RCS. Thus, development of a gashopper CRS technology could result in a major cost saving to the commercial industry.



Robert Zubrin

Pioneer Astronautics

445 Union Blvd., Suite 125

Lakewood , CO 80228 - 0000

NAME AND ADDRESS OF OFFEROR (Firm Name, Mail Address, City/State/Zip)

Pioneer Astronautics

445 Union Blvd, Suite 125

Lakewood , CO 80228 - 0000