PROJECT EXODUS ENAE 412: NASA/USRA Project Dr. Mark Lewis, Advisor Period: January 23,1990 - UM-AERO-90-28
Overall Mission Concept: Project Exodus
Goal: To design a manned Mars mission for the year 2025, focusing on addressing major challenges in propulsion, life support, structure, trajectory, and cost.
Architecture: Employs a three-part system involving:
A Hypersonic Waverider (passenger vehicle)
A Cargo Ship (unmanned supply vehicle)
A NIMF (Nuclear Indigenous Martian Fuel) Shuttle/Lander
Key Features: Venus aero-gravity assist for the waverider, a nuclear-electric propulsion for the cargo ship, and a nuclear-thermal (solid core) propulsion for the NIMF and waverider return.
I. Waverider (Passenger Vehicle)
Design Philosophy: Emphasizes a shock-wave riding design for optimal lift and minimal pressure leakage with high L/D ratios. Uses a semi-active heat pipe cooling system with multiple layers for protection during atmospheric maneuvers. Double leading edge design; the first leading edge is jettisoned in low Mars orbit.
Materials: Primarily uses three-dimensional Advanced Carbon-Carbon (ACC) composite due to its lightweight, stiffness, strength, and high temperature performance. Iridium coating on the leading edge for oxidation resistance. Refractory ceramic coatings are used on other portions of the vehicle.
Trajectory:
Earth to Venus: Launched from Space Station (chemical boosters), performs aero-gravity assist (AGA) maneuver at Venus, resulting in delta-v and deflection angle for Mars transit.
Venus to Mars: Docks with cargo ship in low Martian orbit (LMO).
Mars to Earth: Uses a nuclear-solid core engine, and aero-braking at Earth to slow down for docking.
Aero-Gravity Assist (AGA): A high-lift vehicle, capable of balancing the gravitational and centrifugal forces to maintain a constant altitude. L/D ratios of 7-10 are achievable in the Citherean atmosphere, thus maximizing the time spent in the atmosphere for velocity change.
Propulsion (Mars transit): Uses chemical boosters to leave Earth, jettisoning them before Venus maneuver. Return propulsion uses a solid core nuclear engine (jettisoned before aero-braking at Earth).
Propulsion (Earth Departure): Fuel module uses liquid oxygen and hydrogen tanks with lightweight chemical engines.
Propulsion (Mars Return): Uses a solid core nuclear engine model derived from the Phoebus 2-A engine with composite modifications for an 1150 sec Isp. A high mass flow rate for shortened burn time and U-235 fuel will be used. A pure beryllium reflector will replace the standard materials for improved neutron leakage control.
Life Support: Integrated system involving carbon dioxide removal, oxygen and nitrogen generation, and water reclamation. Uses an electrochemical depolarization carbon dioxide concentrator (EDC) to remove carbon dioxide and static feed water electrolysis for oxygen generation, combined with the Sabatier process for CO2 reduction. VAPCAR (vapor phase catalytic ammonia removal) is used for water reclamation.
Power: Utilizes a deployable advanced photovoltaic array to power life support, communications, and onboard computers.
Microgravity Countermeasures: On-board centrifuge (rotating beds) for each astronaut to combat muscle atrophy and bone thinning. Injections of a calcium based drug for help with bone demineralization.
Crew: A mixed-gender international crew with strict requirements. Contraceptives will be part of the mission.
Medical Facilities: Onboard medical bay (HMF) with diagnostic and treatment equipment, including specialized equipment for use in micro-gravity and for treatment of bone demineralization and calcium loss.
Radiation Shielding: A "hot" room for solar flares and sufficient shielding for transit thru Van Allen Belts. For the surface, base will be buried to shield from radiation.
Key Challenges: Managing hypersonic heating during Venus AGA, and long-term effects of microgravity on crew.
II. Cargo Ship (Unmanned Supply Vehicle)
Design: A long truss structure designed to carry Martian base equipment, the NIMF, and return fuel to Low Mars Orbit (LMO). Modular design to ease assembly in space.
Materials: Primarily titanium, graphite epoxy, and aluminum alloys for the truss, fuel tanks, and capsules.
Propulsion: Employs a nuclear-electric propulsion (NEP) system with Magnetoplasmadynamic (MPD) thrusters and ion attitude control engines using argon as a propellant. Provides a low thrust but a high specific impulse.
Trajectory: Follows a low-thrust spiral path to Mars with a total transit time of 601 days.
Key Contents: Unassembled Martian base, NIMF shuttle/lander, surface life support system, and return fuel/engine for the waverider.
Reentry: The NIMF, cargo capsules and nuclear reactor will have ballistic reentries in the Martian atmosphere using a blunt heat sink shape for thermal protection.
Power: Multi-megawatt nuclear power plant. The reactor is a 5MW distributor heat transport design which will also be used on the Martian base. A neutron reflector is used to prevent leakage of neutrons from the core. The radiator system is used as both a thermal control device as well as a heat shield.
Key Challenges: Integrating large and diverse payloads into the cargo vehicle, as well as shielding from radiation.
III. NIMF (Nuclear Indigenous Martian Fuel) Shuttle/Lander
Design: A nuclear powered vehicle that acts as a shuttle as well as a lander. Constructed of ACC, Kevlar and Graphite-Epoxy materials and with an aluminum honeycomb for its internal structure.
Propulsion: Utilizes an indigenous Martian fuel of liquid carbon dioxide for ascent and descent propulsion, and uses hydrogen during the initial descent. Employs a solid core nuclear engine (based on a Phoebus 2-A model) as its power source.
Fuel: Utilizes liquid carbon dioxide(LCO2) which will be extracted from the Martian atmosphere.
Missions: Transports astronauts to the surface from LMO, transports astronauts across the surface (hops) for exploration, and returns them to LMO for rendezvous with the waverider.
Exploration: Has a 650 mile range and a limited number of 5 missions before refueling.
Key Challenges: Providing a reliable nuclear-thermal engine, and the design of a system that can produce propellant from indigenous Martian materials.
IV. Surface Mission
Base Construction: A prefabricated geodesic dome designed to be partially buried using robotic rovers and explosives. An internal lining will provide an airtight seal from the external atmosphere.
Radiation Protection: The base will be partially buried and additional sandbagging will be used to reduce radiation exposure to the crew.
Energy: The 5 MW power plant from the cargo ship will be used to power the base operations, including gas extraction.
Rover: A legged vehicle will be used to transport cargo, assist in construction, and for exploratory missions near the base.
Scientific Objectives: A wide variety of geological, biological, paleontological, and meteorological experiments, with an open invitation for external research proposals.
Key Challenges: Radiation protection for crew, life support, establishing an effective communications network, and the long term effects of low gravity on humans.
V. Mission Cost
Analysis: Model based on vehicle mass and personnel. The 1990 costs will be inflated to 2012 values.
Cost Breakdown (2012 $):
Waverider: $92.56 billion
Cargo ship: $101.243 billion
Total mission cost = $193.803 billion.
Factors: Costs were calculated for Earth to Space Station launches, construction at the Space Station, and fuel storage costs. Personnel, research and development and systems integration are included.
Key Considerations: Keeping mass at a minimum is paramount to controlling costs.
Key Technological Considerations Throughout the Mission
Advanced Materials: Primarily ACC for weight reduction and thermal management.
Nuclear Technology: Solid core and nuclear-electric propulsion, plus the use of a reactor to generate power on the surface.
Autonomous Operations: Use of robotic systems for assembly and planetary surface activities.
Indigenous Resources: The capability to extract propellant from Martian atmosphere is key for long term operations.
Overall Conclusions:
Project Exodus is a complex and ambitious plan to land a manned mission on Mars. The system design is highly reliant on advanced technology, particularly in new materials, propulsion systems and autonomous systems.
It emphasizes a multi-part strategy, including separate launch systems for the crew and cargo, as well as the utilization of indigenous resources on Mars.
The long term success of the mission hinges on research and development progress in many areas and international cooperation to finance the mission.
Overall Mission Concept: Project Exodus
Goal: To design a manned Mars mission for the year 2025, focusing on addressing major challenges in propulsion, life support, structure, trajectory, and cost.
Architecture: Employs a three-part system involving:
A Hypersonic Waverider (passenger vehicle)
A Cargo Ship (unmanned supply vehicle)
A NIMF (Nuclear Indigenous Martian Fuel) Shuttle/Lander
Key Features: Venus aero-gravity assist for the waverider, a nuclear-electric propulsion for the cargo ship, and a nuclear-thermal (solid core) propulsion for the NIMF and waverider return.
I. Waverider (Passenger Vehicle)
Design Philosophy: Emphasizes a shock-wave riding design for optimal lift and minimal pressure leakage with high L/D ratios. Uses a semi-active heat pipe cooling system with multiple layers for protection during atmospheric maneuvers. Double leading edge design; the first leading edge is jettisoned in low Mars orbit.
Materials: Primarily uses three-dimensional Advanced Carbon-Carbon (ACC) composite due to its lightweight, stiffness, strength, and high temperature performance. Iridium coating on the leading edge for oxidation resistance. Refractory ceramic coatings are used on other portions of the vehicle.
Trajectory:
Earth to Venus: Launched from Space Station (chemical boosters), performs aero-gravity assist (AGA) maneuver at Venus, resulting in delta-v and deflection angle for Mars transit.
Venus to Mars: Docks with cargo ship in low Martian orbit (LMO).
Mars to Earth: Uses a nuclear-solid core engine, and aero-braking at Earth to slow down for docking.
Aero-Gravity Assist (AGA): A high-lift vehicle, capable of balancing the gravitational and centrifugal forces to maintain a constant altitude. L/D ratios of 7-10 are achievable in the Citherean atmosphere, thus maximizing the time spent in the atmosphere for velocity change.
Propulsion (Mars transit): Uses chemical boosters to leave Earth, jettisoning them before Venus maneuver. Return propulsion uses a solid core nuclear engine (jettisoned before aero-braking at Earth).
Propulsion (Earth Departure): Fuel module uses liquid oxygen and hydrogen tanks with lightweight chemical engines.
Propulsion (Mars Return): Uses a solid core nuclear engine model derived from the Phoebus 2-A engine with composite modifications for an 1150 sec Isp. A high mass flow rate for shortened burn time and U-235 fuel will be used. A pure beryllium reflector will replace the standard materials for improved neutron leakage control.
Life Support: Integrated system involving carbon dioxide removal, oxygen and nitrogen generation, and water reclamation. Uses an electrochemical depolarization carbon dioxide concentrator (EDC) to remove carbon dioxide and static feed water electrolysis for oxygen generation, combined with the Sabatier process for CO2 reduction. VAPCAR (vapor phase catalytic ammonia removal) is used for water reclamation.
Power: Utilizes a deployable advanced photovoltaic array to power life support, communications, and onboard computers.
Microgravity Countermeasures: On-board centrifuge (rotating beds) for each astronaut to combat muscle atrophy and bone thinning. Injections of a calcium based drug for help with bone demineralization.
Crew: A mixed-gender international crew with strict requirements. Contraceptives will be part of the mission.
Medical Facilities: Onboard medical bay (HMF) with diagnostic and treatment equipment, including specialized equipment for use in micro-gravity and for treatment of bone demineralization and calcium loss.
Radiation Shielding: A "hot" room for solar flares and sufficient shielding for transit thru Van Allen Belts. For the surface, base will be buried to shield from radiation.
Key Challenges: Managing hypersonic heating during Venus AGA, and long-term effects of microgravity on crew.
II. Cargo Ship (Unmanned Supply Vehicle)
Design: A long truss structure designed to carry Martian base equipment, the NIMF, and return fuel to Low Mars Orbit (LMO). Modular design to ease assembly in space.
Materials: Primarily titanium, graphite epoxy, and aluminum alloys for the truss, fuel tanks, and capsules.
Propulsion: Employs a nuclear-electric propulsion (NEP) system with Magnetoplasmadynamic (MPD) thrusters and ion attitude control engines using argon as a propellant. Provides a low thrust but a high specific impulse.
Trajectory: Follows a low-thrust spiral path to Mars with a total transit time of 601 days.
Key Contents: Unassembled Martian base, NIMF shuttle/lander, surface life support system, and return fuel/engine for the waverider.
Reentry: The NIMF, cargo capsules and nuclear reactor will have ballistic reentries in the Martian atmosphere using a blunt heat sink shape for thermal protection.
Power: Multi-megawatt nuclear power plant. The reactor is a 5MW distributor heat transport design which will also be used on the Martian base. A neutron reflector is used to prevent leakage of neutrons from the core. The radiator system is used as both a thermal control device as well as a heat shield.
Key Challenges: Integrating large and diverse payloads into the cargo vehicle, as well as shielding from radiation.
III. NIMF (Nuclear Indigenous Martian Fuel) Shuttle/Lander
Design: A nuclear powered vehicle that acts as a shuttle as well as a lander. Constructed of ACC, Kevlar and Graphite-Epoxy materials and with an aluminum honeycomb for its internal structure.
Propulsion: Utilizes an indigenous Martian fuel of liquid carbon dioxide for ascent and descent propulsion, and uses hydrogen during the initial descent. Employs a solid core nuclear engine (based on a Phoebus 2-A model) as its power source.
Fuel: Utilizes liquid carbon dioxide(LCO2) which will be extracted from the Martian atmosphere.
Missions: Transports astronauts to the surface from LMO, transports astronauts across the surface (hops) for exploration, and returns them to LMO for rendezvous with the waverider.
Exploration: Has a 650 mile range and a limited number of 5 missions before refueling.
Key Challenges: Providing a reliable nuclear-thermal engine, and the design of a system that can produce propellant from indigenous Martian materials.
IV. Surface Mission
Base Construction: A prefabricated geodesic dome designed to be partially buried using robotic rovers and explosives. An internal lining will provide an airtight seal from the external atmosphere.
Radiation Protection: The base will be partially buried and additional sandbagging will be used to reduce radiation exposure to the crew.
Energy: The 5 MW power plant from the cargo ship will be used to power the base operations, including gas extraction.
Rover: A legged vehicle will be used to transport cargo, assist in construction, and for exploratory missions near the base.
Scientific Objectives: A wide variety of geological, biological, paleontological, and meteorological experiments, with an open invitation for external research proposals.
Key Challenges: Radiation protection for crew, life support, establishing an effective communications network, and the long term effects of low gravity on humans.
V. Mission Cost
Analysis: Model based on vehicle mass and personnel. The 1990 costs will be inflated to 2012 values.
Cost Breakdown (2012 $):
Waverider: $92.56 billion
Cargo ship: $101.243 billion
Total mission cost = $193.803 billion.
Factors: Costs were calculated for Earth to Space Station launches, construction at the Space Station, and fuel storage costs. Personnel, research and development and systems integration are included.
Key Considerations: Keeping mass at a minimum is paramount to controlling costs.
Key Technological Considerations Throughout the Mission
Advanced Materials: Primarily ACC for weight reduction and thermal management.
Nuclear Technology: Solid core and nuclear-electric propulsion, plus the use of a reactor to generate power on the surface.
Autonomous Operations: Use of robotic systems for assembly and planetary surface activities.
Indigenous Resources: The capability to extract propellant from Martian atmosphere is key for long term operations.
Overall Conclusions:
Project Exodus is a complex and ambitious plan to land a manned mission on Mars. The system design is highly reliant on advanced technology, particularly in new materials, propulsion systems and autonomous systems.
It emphasizes a multi-part strategy, including separate launch systems for the crew and cargo, as well as the utilization of indigenous resources on Mars.
The long term success of the mission hinges on research and development progress in many areas and international cooperation to finance the mission.