Earth-Moon Transport Doroteo Garcia Kazuya Suzuki Patrick Zeitouni

2-Dec-04 USC 2004 AME 557 Space Exploration Architecture Overview  Mission Statement  Options of transportation systems  Choices of transportation systems  Summary

2-Dec-04 USC 2004 AME 557 Space Exploration Architecture Mission Statement Provide a safe way to deliver both crews and cargos to the surface of the Moon relative cheaply Flexible and sustainable access to anywhere on the lunar surface Growth to enable other missions  Routine travel in Cislunar space  Missions to Mars

2-Dec-04 USC 2004 AME 557 Space Exploration Architecture Options (1/2) 1. Direct Ascent (DA) Fly directly to the moon & back with a single crewed vehicle 2. Earth Orbit Rendezvous (EOR) Multiple vehicles rendezvous at LEO, then depart to the moon 3. Lunar Orbit Rendezvous (LOR) Separate landing vehicle, rendezvous in lunar orbit (Apollo method) 1 2 3

2-Dec-04 USC 2004 AME 557 Space Exploration Architecture Options (2/2) 4. Lunar Surface Rendezvous (LSR) Astronauts rendezvous with the “Earth Return Vehicle” on the Lunar surface 5. Rendezvous at 1 st Lagrange Point Separate landing vehicle, rendezvous at L1 station 6. Use of High Isp/low thrust propulsion Spiral trajectory, using Lunar resonance for gravity assists (like SMART-1) 4 6 5

2-Dec-04 USC 2004 AME 557 Space Exploration Architecture All the Options ModeLaunch MassFlexibilityComplexityAbort AvailabilityMass Growth 1 – Direct AscentHigh LowHighBad 2 – EORMed HighOK 3 – LORLow HighMedOK 4 – LSRLowMedHighLowGood 5 – L1 StationLowHighMed Good 6 – High IspLowHighMedLowGood

2-Dec-04 USC 2004 AME 557 Space Exploration Architecture Chosen Systems  Crew Transport: Rendezvous at L1 station  Cargo Transport High Isp/low thrust propulsion

2-Dec-04 USC 2004 AME 557 Space Exploration Architecture Crew Transportation Components  Crew Transfer Vehicle (CTV) 2 crew, 4 passengers  L1 Station Untended, simple Communications node Orbital parking spot  Lunar Transfer Vehicle (LTV) 2 crew, 4 passengers Reusable single stage Refueled at L1 and surface base

2-Dec-04 USC 2004 AME 557 Space Exploration Architecture Crew Transportation Architecture  Video clip

2-Dec-04 USC 2004 AME 557 Space Exploration Architecture Crew Transportation Selection  Low launch mass  Less sensitive to payload mass growth  Access to all points on the lunar surface  Mission flexibility  Allow people for extended stay  Continuous Abort capability  Much interest in L1  Need to maintain a station at L1  Multiple rendezvous required  No immediate rescue possible during certain mission phases (as in Apollo 13) Advantage Disadvantage

2-Dec-04 USC 2004 AME 557 Space Exploration Architecture Cargo Transportation Architecture  Launch Vehicle HLLV (Shuttle C) Reusable strap on boosters and main engines (SRB & SSME) Alternatively, use multiple EELV heavies  Cargo Delivery Vehicle (CDV) Spiral orbit Approx 1 year transfer time Reusable Electric propulsion SSME Pod detaches and returns to Earth CDV Docks with payload and begins long journey Launch

2-Dec-04 USC 2004 AME 557 Space Exploration Architecture Cargo Transportation Architecture  Unmanned Cargo Landing Vehicle Autonomous Lunar Lander Reusable Refuel at L1 and lunar surface bases  Advantages Cheaper than chemical propulsion Enables payload mass growth  Disadvantages Long trip time Higher radiation exposure CDV undocks after reaching Lunar orbit UCLV docks with payload and takes it down to the surface 4 5

2-Dec-04 USC 2004 AME 557 Space Exploration Architecture Summary  Chose to separate crew and cargo Focus on safety for crew Focus on cost for cargo  Architecture provides mission flexibility & versatility  Future growth Payload Mass Routine Earth-Moon travel Gateway to interplanetary space

2-Dec-04 USC 2004 AME 557 Space Exploration Architecture References  An Earth – Moon Transportation system by Patrick Zeitouni    

2-Dec-04 USC 2004 AME 557 Space Exploration Architecture Crew Transport dV Budget

2-Dec-04 USC 2004 AME 557 Space Exploration Architecture Cargo Transport dV Budget