1. Near-Term Mars Colonization -A DevelopSpace Project- May 25 th, 2008

2. Agenda Transportation update Minimalist transportation concept Power update SVN update

3. Transportation Update

4. Solar Electric Propulsion (SEP) Could be used to raise from LEO to HEO System Mass = ~120% Payload Mass Paper by Gordon Woodcock (AIAA 2004-3643) – Requires 41mT of Xenon (for 50 mt Payload) » (Annual world production = 53mT)

5. Baseline Delta-V = 4000 m/s PMF = 0.125 Specific Impulse = 450 sec Chemical Propulsion

7. TMI Stage Mass vs Payload Mass From LEO, the TMI payload mass is ~50% the mass of the TMI Stage – Ideally, the TMI payload mass would be equal to the TMI stage mass to utilize one launch vehicle Solutions – Break TMI Stage into two stages One large & one small – Have launch vehicle place TMI stage and payload into highly elliptical orbits Reduce TMI Delta-V to ~2600 m/s – No analysis on feasibility done yet

8. Mars Orbit Insertion and EDL Most common approach – Aero-capture followed by aero-assist EDL System Masses vary greatly – DRM-1 & DRM-3 assume 28- 33% of TMI Mass required for “descent system” – Mars Direct assumes 35% of TMI Mass required – Robert Braun (Georgia Tech) mentions 70% of TMI Mass required for “descent system” 40% for orbit insertion 30% for descent and landing IMLEO [kg]100000 TMI Stage "Dry" [kg]8380 TMI Stage "Propellant" [kg]58659 Orbit Insertion System [kg]13184 Descent and Landing System [kg]9888 Payload [kg]9888 Based on chemical propulsion & Braun’s numbers 10% of IMLEO mass can be landed on Mars

9. In-Space Crew Considerations How does the crew get to the surface of Mars? Earth to LEO – Separate launch and rendezvous – Launched in transit or Mars habitat LEO to Mars – Is a unique habitat required? – Zero-gravity concerns Artificial Gravity

10. Mars Habitat Mars Descent/Ascent Vehicle Payloads and Systems30325.213467.2 1.0 Power Systems59884762 2.0 Avionics153 3.0 Environmental Control & Life Support System3948.91037.6 4.0 Thermal Management System2912.1527.4 5.0 Crew Accommodations3502.9727.7 6.0 EVA Systems1174.41085 7.0 In-situ Resource Utilization1650 8.0 Mobility01200.4 9.0 Science829.9301.2 10.0 Structure1861.31339.8 Margin (15%)1775.11415.1 Food6840360 Crew0558

11. Mobility Strategies AdvantagesDisadvantagesComments EVA SuitsSimplestVery limited range Not feasible with multiple stationary landers/habitats Unpressurized Rovers Simple Increased range vs. EVALimited rangeBeing developed for lunar exploration Pressurized Rovers Simple Multi-day trips Higher mass than UPR Range limited by capacityBeing developed for lunar exploration AircraftIncreased rangeUntestedIs this even possible? Ballistic VehiclesIncreased range Untested ComplexUse of ISRU a possibility Mobile Base Move entire habitats to desired locationsMass intensiveEither by roving or ballistic

12. Minimalist Transportation Concept

13. Transportation Challenges How do we transport crew and cargo to the Martian surface using 25 mt launch vehicles? – 25 mt is “worst-case scenario” – Larger payload capabilities would facilitate transportation and also lead to scaling benefits Specific challenges: – Launch and LEO orbit assembly – Mars aerocapture and EDL Ballistic coefficient (entry body mass, diameter, shape) Altitude at Mach 3 / aeroshell separation – Propulsive descent (800 m/s assumed for now) – Final landing GN&C, landing error reduction – Hazard avoidance Falcon 9 Heavy assumed as reference LV – ~28 mt to 300 km LEO – ~4 m x ~10 m cylinder of usable volume in shroud Image credit: Space Exploration Technologies, Inc. Falcon 9 Heavy

14. Mars Aerocapture and Entry Vehicle Entry vehicle is based on conic blunted body – 20 degree side-wall angle – Drag coefficient: ~1.6 – L/D: ~0.3 Total mass is 12 mt, leading to a ballistic coefficient of around 600 kg/m2 – Mach 3 altitude ~ 5 km Final descent propulsion based on MMH / N2O4 – Isp = 320 s – 8 tanks (4 fuel, 4 oxidizer) Cargo to surface: ca. 5 mt

15. Cargo Transportation Concept Transportation concept based on dual blunt-shaped entry bodies – Reduces ballistic coefficient per entry body (~ 600 kg/m2) – Allows for simple blunt-body shape Entry bodies are launched together with additional cruise systems – Solar arrays, batteries, radiators – Entry bodies separate prior to aerocapture and aeroentry 2 Earth departure stages are launched after the entry bodies – Stages dock to entry bodies for dual burn Earth departure Initial analysis indicates that ~25 mt can be injected towards Mars using LOX / kerosene stages – ~10 mt useful cargo mass on Mars surface (~ 5 mt per entry body) Solar array Earth-Mars transit configuration Entry body 1 Entry body 2 Launch configuration TMI stack Earth departure stage 1 Earth departure stage 2

16. Crew Transportation Concept Crew transportation with entry body (cargo) and additional transit habitat – 2 sets of solar arrays, batteries, and radiators – Transit habitat is jettisoned prior to aerocapture 2 Earth departure stages are launched separately and docked – Dual burn Earth departure – LOX / kerosene propulsion Initial analysis indicates that 2-3 crew can be delivered to Mars surface this way – Crew can be sustained for 30+ days on surface after landing – Unpressurized mobility delivered with crew Solar arraysSolar array Earth-Mars transit configuration Entry body Launch configuration TMI stack Earth departure stage 1 Earth departure stage 2 Transit hab

17. Transportation Results & Forward Work 4-6 crew can be transported to Mars with 6 Falcon 9 heavy launches – Launch cost of ca. $ 600 Mn (ca. $ 100 Mn per launch) 3 Falcon 9 heavy launches can deliver a minimum of 10 mt of useful mass to the Martian surface – Equivalent to 26-month consumables demand for 4 crew Forward work: – More detailed design of aeroshell and descent stage – More detailed design of Earth departure propulsion Including propellant type trade – Investigation of different entry body shapes

18. Power Update

19. Surface Power Architecture Tree The basic type of analyses that was carried out: – Equal energy analysis: all systems provide the same usable energy per day (for photovoltaic systems this means increased power generation during the day) Primary energy generation Nuclear fission Photovoltaic conversion (“solar”) Secondary energy generation Not required Batteries Fuel cell + electrolysis Energy storage Not required Batteries H 2 + O 2 Batteries + radioisotope Batteries Fuel cell + electrolysis + radioisotope H 2 + O 2 Tracking arrays? N/A Yes NoYes No Yes NoYes No Radioisotope Not required Yes No

20. Modeling Created model for Mars solar arrays based on following major requirements: – Array must be sized for end-of-mission power requirements – If several missions go to same site, supplementary arrays are brought each mission to make up for degradation – Array must be sized to provide the required power during the year’s minimum incident solar energy period Model Assumptions: – On Mars, optical depth of 0.4 (equivalent to hazy skies) – Tracking arrays at both locations are multi-axis and keep incident flux perpendicular to array over the day – Nighttime power of 20 kW, with daytime power enforced when sun is 12 degrees above the horizon – Mars analysis done for an equatorial location (actually not optimal location for solar power on Mars): Optimal location at 31° N, with a minimum of 6.57(kW-h/m^2/sol) and 49% daylight/sol for a period of 100 sols Northern latitudes better than corresponding southern latitude

21. Model Inputs and Outputs Inputs: – Minimum solar energy – Eclipse Time – Daytime/nighttime power req. – Power distribution eff. – Solar array eff. – Degradation per year – Array lifetime – Optical depth – Latitude – Array packing density – Battery type Outputs: – Array area – System mass – System volume

22. Mars Results

23. Mars Results Continued

24. Other Considerations for Large Solar Array Fields on Mars Deployment time: – Considered a 10,000 m^2 rollout array field which will provide 63kW average power for about 100kW daytime power – Assume array blankets are 2m wide for easy storage and handling by two astronauts – Assume each blanket weighs 100lbs again for easy handling – With 0.06 kg/m^2 expected array density, need only 14 blankets total – Assume astronauts can unroll array at a walking speed of 1m/s, requires only 3hrs for unrolling – Most time will be needed for unloading positioning and hookup, if assume 1hr for this for each array, total deployment time approximately 17 work hours for 2 crew Power delivery during deployment: – If we are conservative and say deployment takes 1 week, we need either a 10kW RTG or fuel cell system to provide 10kW power over the week – RTG system would be approximately 1200kg and 0.6 m^3 – If use RFC, need 2400kg system with volume 8.4 m^3

25. Future Work Reassess architecture options in MinMars colony context. Previous power analysis for shorter round trip mission. Operations considerations such as dust removal and maintenance. Dust storm power generation.

26. SVN Update

27. Current SVN Folder Structure Meetings – Folders with telecon slides Models & Analysis – Folders with individual models and results (spreadsheets, presentations, CAD files, etc.) Users – Folders for individual users

28. Backup Slides

29. Project Definition Mid-May 2008 July 15, 2008Early September 2008 Focus on fixed crew-size “toehold” on Mars as alternative to exploration program Focus on expansion of “toehold” to mostly self-sustained colony Follow-on projects Integration of results (lead: Wilfried) Finance and costing (lead: ?) Outpost re-supply (lead: Wilfried) In-Space Transportation (lead: Arthur) Surface Infrastructure (lead: Arthur) Surface Operations (lead: Arthur) Surface Power & Thermal (lead: Chase) Expansion analysis

30. Operational Architecture The overall operational architecture for the initial toehold is based on one- way flights delivering cargo and crew to the Martian surface – Potentially with an emergency return capability Mars capture is assumed to be accomplished by aerocapture Subsequent lifting entry and propulsive descent are used to deliver payloads to the single surface outpost site – Outpost location is subject to a variety of factors (insolation, water, elevation) The exact size and payload capability of each lander depends on the Earth departure architecture and entry body chosen Mars orbit Earth orbit Earth departure architecture 26 months

31. Toehold Location: Topography

32. Toehold Location: Solar Power

33. Toehold Location: Water

34. General Study Objectives Carry out an assessment of re-supply needs for the outpost given different technologies – Including high-closure life support, ISRU Identify key re-supply drivers and carry out in-depth analyses Identify interesting technologies with high payoff in re- supply mass reduction – Carry out initial modeling and testing of these technologies Formulate plan for further technology development

35. Mars Surface Habitat Architectures 1-5 Open loop Water regeneration (95%) Regenerative CO 2 removal Completely dehydrated food Washing machine

36. Mars Surface Habitat Architectures 5-9 Cryogenic oxygen Water electrolysis + Sabatier reactor Water electrolysis Water electrolysis + Sabatier reactor + methane pyrolysis

37. Mars Surface Habitat Architectures 9-13 Zirconia electrolysis, scaled-upZirconia electrolysis, scaled-down Zirconia electrolysis + water electrolysis + Sabatier reactor + methane pyrolysis Zirconia electrolysis, no water electrolysis, Sabatier reactor, methane pyrolysis

38. Preliminary Insights Existing technologies allow for re-supply masses per opportunity of ~2 mt / person – This includes fairly conservative tare fractions on pressurized logistics and fluid re-supply Remaining high-mass re-supply items are: – Food – Spare parts (fans, multi-filtration beds, etc.) – Hygiene & health re-supply (soap, first-aid, etc.) – Hydrogen for ISRU

39. Food Logistics Reduction Many options for closure of the food loop have been investigated over the decades Two major families of options: – 1. Chemical regeneration of food from waste Synthesized chemicals suitable for long-term ingestion include: glucose, glycerin, ethanol, formose sugars – 2. Biological regeneration of food from waste Algae (also for CO 2 regeneration) Higher plants (wheat, corn, vegetables, etc.) Animals (fish, chicken)

40. Mars Wish List

41. Transportation Automated Mars landing and hazard avoidance navigation systems Mars in-situ propellant production friendly rocket combustion / performance characterization (C2H4/LOX; CH4/LOX); more important if people want to come back Large-scale (20mt+) Mars aero-entry (and EDL more generally) technology Low mass, cost, power and ideally autonomous deep-space (out to at least ~2 AU) navigation systems (software, hardware)

42. Power Automated, large scale (football field+) solar array transport, surface deployment, and maintenance systems High energy density electrical power storages systems (aiming in particular towards high energy density relative to Earth imported mass) Mars surface internal combustion engines (LOX, plus various fuels, e.g., C2H4, CH4, CO, etc), possibly with water exhaust reclamation.

43. Life Support, Logistics, ISRU Mars atmosphere collection systems (at minimum CO2; adding N2 and Ar is useful; H2O depends on energy/mass intensity relative to other options) Mars permafrost mining systems (for varying wt% H2O); note, this is much easier than mining putative lunar ice Good, high capacity Mars surface cryocoolers (options for just soft/medium cryogens (e.g., LOX, CH4, C2H4), or also for hard cryogen (LH2)) Earth-Mars hydrogen transport systems (not necessarily as LH2) Basic ISRU chemical processing systems (e.g., H2O electrolysis, Sabatier, RWGS, CO2 electrolysis, ethylene production, etc.) High closure physical-chemical life support systems (e.g., air revitalization, water recycling) "Food system" for food supplied from Earth. Consider being able to survive on food shipped 5 years ago. Mars surface food production systems Simple in-situ manufacturing systems (e.g., for spare parts) Simple raw materials production (e.g., plastics such polyethylene, epoxies, ceramics, etc.)

44. Outpost Ops and Surface Exploration Mars surface communication and navigation systems (e.g., for rovers), sans extensive satellite constellation Very high data rate Mars-Earth back-haul comm system Good Mars surface EVA suits Data collection, analysis in support of landing site / outpost location selection Very long distance surface mobility systems (including with people) Solar flare / SPE warning systems

45. Mass Budget for Habitat-1 Mars DirectDRM-3MSMExplanation for MSM figures Habitat Module Structure55.54.8Scaled from DRM-3 Furniture and Interior101.5 Life Support System34.73.8NASA model for crew of six Comm/Info0.20.3 DRM-3 Hydrogen and Hab ISRU0.400 Health Care1.300 Thermal00.60.5DRM-3 Scaled Crew accommodation011.50 Spares and Margin3.500Included in individual listings Science100 Crew0.40.50.4 Surface power (reactor)01.75At least 25 kWe needed Power Distribution00.3 DRM-3 Scaled EVA Suits0.411DRM-3 Open Rovers0.80.50Mass budgeted with surface power Pressurized Rover1.400 Consumables703.298% closed H20/02 + food (=0.630 kg/per/day for 600 days) EVA Consumables02.30Produced by ISRU on MAV and Hab Descent fuel cell131.3 Reaction Control System0.50 Mars Direct Total Landed26.931.922.6Total of Above

46. Mass allocations for Mars Direct components on surface of Mars ERV componentsmTHabitat componentsmT ERV cabin structure3Habitat strucure5 Life Support System1 3 consumables3.4Consumables7 Solar Arrays (5 kW)1 1 Reaction Control System0.5Reaction Control System0.5 Communications and Information Management0.1Communications and Information Management0.2 Furniture and Interior0.5Furniture and Interior1 Space Suits (4)0.4Space Suits (4)0.4 Spares and Margin (16%)1.6Spares and margin (16%)3.5 Aeroshell (for Earth Return)1.8Pressurized Rover1.4 Rover0.5Open Rovers (2)0.8 Hydrogen Feedstock6.3Lab Equipment0.5 ERV Propulsion stages4.5Field Science Equipment0.5 Propellant Production Plant0.5Crew0.4 Nuclear reactor (100 kW)3.5 Total Mass28.6 25.2