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NASA has developed and tested a large parafoil for use in landing the International Space Station crew return vehicle. A series of tests using low-velocity airdrop pallets and prototype lifting bodies ights has demonstrated that the parafoil recovery system is a viable option for safely landing a crewed vehicle. The aerodynamic characteristics of the parafoil system have been determined through a series of ight-test maneuvers and subsequently successfully modeled using an eight-degree-of-freedom simulation program. An introduction to the requirements for the crew return vehicle, a description of the parafoil system, an overview of the testing performed including several signi cant ndings, a description of the techniques used to assess the aerodynamic performance of the parafoil system, and a discussion of the simulation of the parafoil system are presented. Nomenclature AR= aspect ratio b= parafoil span C L ; C D = lift and drag coef cients Cm c=4= parafoil system pitching moment coef cient about c=4 Cn r = yawing moment due to yaw rate Cn ± f = yawing moment due to control line de ection difference between left and right aps c = parafoil chord c=4 = quarter chord point on the parafoil keel HR = velocity vector heading rate HR wc = wind-corrected heading rate N q = dynamic pressure RA, µ r = parafoil rigging angle (X pf to parafoil keel) R=b = line length ratio (average suspension line length divided by span) S = parafoil reference area t = time, where t 1 is time at rst data point and t 2 time at second data point V h wc = wind-corrected horizontal velocity V tot = total velocity V w = wind velocity V x = east velocity V y = north velocity V z = vertical velocity W pf = weight of the parafoil system, including rigging, but not payload W sys = weight of the parafoil system and payload W =S = wing loading (payload weight divided by parafoil area) X cg ; Y cg = distance from the con uence to the parafoil system c.g. in parafoil coordinates X PL = payload body axis parallel to payload's bottom surface X pf ; Z pf = parafoil coordinate system, Z axis originating at the con uence point with Z extending up through c=4 Z c=4 = distance from the con uence to the c=4 ® = parafoil angle of attack relative to keel ® PL = payload angle of attack relative to X PL°= wind-corrected ight-path angle (V wc to horizon) ± f = control line de ection delta µ = parafoil pitch angle (X pf to horizon) ½ = atmospheric density Á w = direction of the wind measured from the north, that is, wind is coming from Á w 9 & b = body yaw rate

The making of oxygen from resources in the Martian atmosphere, known as In Situ Resource Utilization (ISRU), has the potential to provide substantial benefits for future robotic and human exploration. In particular, the ability to produce oxygen on Mars for use in propulsion, life support, and power systems can provide significant mission benefits such as a reducing launch mass, lander size, and mission and crew risk. To advance ISRU for possible incorporation into future human missions to Mars, NASA proposed including an ISRU instrument on the Mars 2020 rover mission, through an announcement of opportunity (AO). The purpose of the the Mars Atmosphere Resource Verification INsitu or (MARVIN) instrument is to provide the first demonstration on Mars of oxygen production from acquired and stored Martian atmospheric carbon dioxide, as well as take measurements of atmospheric pressure and temperature, and of suspended dust particle sizes and amounts entrained in collected atmosphere gases at different times of the Mars day and year. The hardware performance and environmental data obtained will be critical for future ISRU systems that will reduce the mass of propellants and other consumables launched from Earth for robotic and human exploration, for better understanding of Mars dust and mitigation techniques to improve crew safety, and to help further define Mars global circulation models and better understand the regional atmospheric dynamics on Mars. The technologies selected for MARVIN are also scalable for future robotic sample return and human missions to Mars using ISRU.