Enabling The Future: NASA s Routes to Future Large UV/Optical Telescopes in Space

Transcription

1 Enabling The Future: NASA s Routes to Future Large UV/Optical Telescopes in Space April 10, 2003 Space Telescope Science Institute Harley Thronson Director of Technology Office of Space Science National Aeronautics and Space Administration

2 Overview (1): Primer on Enabling the Future Essential Steps for Future OSS Missions 1. Mission Science Goals Clearly Traceable to Agency/OSS Priorities o Strong recommendation by National Academy a good thing 2. Mission Concepts/Analyses that Accomplishes Three Things 1. Priority technology investments and strategy 2. Affordable design that achieves clear science goals 3. Builds upon preceding technologies and stepping stone for subsequent missions o Coordination with other Enterprises/Agencies/nations? 3. Technology Program to Deliver Essential Capabilities 4. Advocacy Within NASA: the NASA Strategic Plan and OSS Strategy 5. Repeat as Necessary

3 Overview (2): Developing Mission Concepts within NASA Creating Future OSS Missions Historically, OSS has not had a formal program to develop future mission concepts and identify the technologies to enable them. This has changed -- somewhat -- in the past couple years via four activities: 1. The NASA Exploration Team (NEXT) (extinct, but POC: H. Thronson) 2. The OSS strategic planning process (POC: M. Allen) 3. The upcoming OSS Vision Missions NRA (POC: M. Allen) 4. Code R (OAT)-funded concept studies (POC: H. Thronson/C. Moore) These ad hoc activities may be coordinated via an Agency-wide analysis and prioritization activity beginning later this spring. => Identification of technology investment priorities are an essential product of these studies.

4 Overview (3): Technology Prioritization within OSS Making Technology Happen Within OSS Historically, OSS has not had many formal programs to develop the technologies necessary to enable future missions. This has changed -- somewhat -- in the past couple years via four activities: 1. The In-Space Propulsion Program 2. The Nuclear Systems Initiative (aka, Prometheus Program) 3. The proposed Advanced Communication initiative 4. Process for FY05 initiatives has just begun 5. Coordinated funding opportunities with Code R/OAT 1. Large optical systems 2. Detectors and sensors, emphasizing large-area IR arrays 3. Very low-power electronics 4. Others: information systems, materials,... => Technology investment priorities are determined via technology roadmapping within OSS Divisions

5 NASA s Vision To improve life here, To extend life to there, To find life beyond. NASA s Mission To understand and protect our home planet To explore the Universe and search for life To inspire the next generation of explorers as only NASA can.

6 Science Priorities Determine Priority Activities (Selected Examples) Science Questions To Explore the Universe... How did we get here? Where are we going? How did the Solar System evolve? Pursuits Planetary sample History of analysis: absolute major Solar age determination System events calibrating the clocks How do humans Effects of adapt to space? deep space on cells What is Earth s Impact of sustainability and human and habitability? natural events upon Earth Are we alone? Is there Life beyond the planet of origin? Activities Origin of life in the Solar System Origin of life in the Universe Destinations Asteroids Moon Mars Venus Measurement of genomic responses to radiation Beyond Van Allen belts Measurement of Earth s vital signs taking the pulse Earth orbits Libration points Detection of biomarkers and hospitable environments Cometary nuclei Europa Libration points Mars Titan

7 Stepping Stones to NASA s Future Each Major Capability Prepares for Subsequent Steps

8 Architecture Concepts to Date: Using the Libration Points Design Reference Missions for Stepping Outward from LEO Telescopes at Sun-Earth L1/L2 Construct, Deploy, and Service Large Science Platforms Go Go Anywhere, Anywhere, Anytime Anytime Lunar Lander Jupiter/Callisto Lunar Exploration Outer Planet Exploration Earth s Earth s Neighborhood Neighborhood Orbital Aggregation & Space Infrastructure Systems (OASIS) Crew Transfer Vehicle Accessible Accessible Planetary Planetary Surfaces Surfaces Outpost at Libration Point Gateway Mars Exploration Tug Earth Earth and and LEO LEO Artificial Gravity Vehicle LEO/ISS 24

9 To Explore the Universe and Search for Life Priority Technologies to Enable the Future Space Transportation Safe, fast, and efficient; aerobraking, electric propulsion, station-keeping RLV NEP Invariant Manifolds Aerobraking Affordable, Abundant Power Solar and nuclear; power management Space Solar Power Crew Health and Safety Counter measures and medical autonomy Optimized Robotic and Human Operations Dramatically higher productivity; onsite intelligence M2P2 L 1 Outpost Artificial Gravity Space Systems Performance Advanced materials and optical systems, detectors/sensors, advanced communication, low-mass, self-healing, self-assembly, self-sufficiency Robonaut Gossamer Telescopes Nanotube Space Elevator

10 Progressive Exploration Capabilities Earth s Neighborhood Capability Accessible Planetary Surface Capability Sustainable Planetary Surface Capability In-space propulsion, Isp>1000 sec, high thrust Power systems, >200 w/kg Integrated Human/ robotic capabilities Crew countermeasures for 100 days Closure of water/air systems Materials, factor of 9 IVHM - Integrated Vehicle Health Monitoring Current launch systems In-space propulsion, Isp>3000 sec, high thrust Power systems, >500 w/kg Robotic aggregation/assembly Crew countermeasures for 1-33 years Complete closure of air/water; options for food Materials, factor of 20 Micro-/Nano Nano- avionics ~$2000/kg Payload: 20 to 40mt In-space propulsion, Isp>3000 sec, high thrust Sustainable power systems Intelligent systems, orbital and planetary Crew countermeasures for indefinite duration Closure of life support, including food ISRU for consumables & spares Materials, factor of 40 Automated reasoning and smart sensing <$2000/kg Payload: 40 to 80mt Now

11 To Explore the Universe and Search for Life Large Optical Systems Mission: Invest in the technologies for the post-jwst optical systems that will be necessary for NASA s search for life beyond the Solar System. Telescope Concept Priority Investments: Lightweight affordable optical materials Precision metrology and wavefront control Robotic and telerobotic systems for remote operation Thermal controls systems Detectors and sensors Collaborations: Academia, JPL, GSFC, DARPA, NRO, and NASA Earth Science Remote Telescope Assembly and Deployment (Animation) Potential Telescope Assembly Capabilities 57

12 Key Elements of Mission Concept Scenarios Studied to Date Selected a large (10 m), lightweight IR/SubMM gossamer telescope, DART, as the baseline design for conducting initial set of studies. This design tests the limits of conventional deployment/assembly technologies Investigated three scenarios for assembly and/or deployment Scenario 1. LEO assembly + E-M L1 deployment--w/astronaut assistance (see Filled Aperture Infrared (FAIR) Telescope Assembly 57 pg presentation from JSC, Dec 01) Scenario 2. E-M L1 assembly & deployment--w/astronaut assistance (see Human & Robot Cooperative Teams 18 pg presentation from JPL, Jul 02) Scenario 3. E-M L1 or E-S L2 fully autonomous deployment (see Summary Report on the NExT Telescope Team Design Workshop from JPL, Sept 02) For astronaut assembly concepts, Scenario 1 assumes Space Shuttle-EVA infrastructure and Scenario 2 assumes a Gateway infrastructure are operational & staffed appropriately for assembly of large structures. Focused on characterizing & prioritizing new technologies needed to accomplish the mission

13 Decision Capture of Team X/DART Design Decision capture methods were used to investigate different design options - Several scenario options piloted to capture: design assumptions, considered design approaches, and rationale for choosing the selected design solutions - The exercise focused on enabling technologies and high-risk design elements The developed decision capture capability can be used to - Identify and challenge critical design elements and sensitivities - Illuminate common-mode risks, FMs, assumptions, and dependencies - Generate design libraries for future use - Provide a single-source representation of multiple decision paths and mission concepts - Auto-generate technology roadmaps Decision capture studies illuminated the need for more/early collaborations among - Scientists (to define/explain science goals) - Area technologists (to suggest the possible enabling technology options) - Systems engineers (to tie together the various facility/technology elements) - Program planners (to ensure that viable options are considered & recorded) - Designers (to capture the design concepts in viewable imagery)

14 Telescope Deployment in LEO 1. Launch LEO-to-L1 Propulsion Stage to Low Earth Orbit on Expendable Launch Vehicle 2. Launch Shuttle to Low Earth Orbit 3. Rendezvous Shuttle to Close Proximity with Propulsion Stage 4. Build Truss Assembly in Shuttle Payload Bay (Image 1) 5. Mate Truss with Spacecraft and Sunshield (Image 2, 3) 6. Rendezvous and Berth Propulsion Stage to Shuttle (Image 4) 7. Mate Completed Telescope with Propulsion Stage (Image 5) 8. Perform final telescope testing and alignment (Image 6) 9. Release telescope 10. Shuttle de-orbit and landing

15 Modified C-Clamp Telescope Stowage Stowed C-Clamp DART in 6-m diameter Delta IV heavy fairing Modified (C-Clamp) 10-m DART configuration Designed for autonomous deployment Deployed DART C-Clamp Configuration

16 Key Results to Date: Large Optical Systems Developed three scenario concepts for implementation of FAIR-DART Scenario 1. LEO assembly + E-M L1 deployment--w/astronaut assistance Scenario 2. E-M L1 assembly & deployment--w/astronaut assistance Scenario 3. E-M L1 or L2 fully autonomous deployment Authored design reports based on JPL Team X design trade studies Devised and tested a technique for capturing the basis of Team X design decisions for mission scenario concepts Conceptualized a method for autonomously deploying gossamer optics Studied autonomous deployment of a large complex space structure Devised a DART configuration capable of being autonomously deployed Initiated a study of contamination of space optics from EVAs, Gateway, & airlock sources Concluded that autonomous deployment of large space structures becomes exponentially more complicated when multiple launch vehicles are needed to lift facility and science elements into the deployment/science location

17 Technology Priorities: Enabling Future Large Optical Systems Robotics - Astronaut assistants (Robonauts/Remote Manipulator System/mini-AERcam) EVA/human infrastructure - Contamination reduction (esp. H2O, CO2, O2, N2); from suits, airlock, Gateway - Improvements in dexterity, accessibility, mobility, stability (incl. hand/foot locks) (see HTCI/THREADs advanced EVA/robotics roadmap) Instrument lightweighting - Reduce by factors of 10! (packaging, electronics, optics) - Simpify sensor arrays to simply systems Telescope structural design, materials, optical alignment - Gossamer design (DART-like structure) vs. lightweight segmented panels - Methods for integrating utilities into structural elements (conn., heaters, actuators) Thermal control of structure and reflective surfaces - Cryocoolers for active cooling - V-Groove radiators for passive cooling (inflatable-rigidizable?) Propulsion - Clean (contamination-free; Xe) and reliable thrusters for pointing/positioning Power Generation/Storage - Gateway robotic operations/astronaut habitat Communications -Large data rate from large detector arrays needs to be transmitted or science is lost

18 Unresolved Issues Quantitative effects of contaminants on reflective surfaces need to be more thoroughly understood and documented - details regarding how much contamination (by constituent) can be tolerated on surfaces to be used for observations in UV, visible, NIR, FIR, etc) Contamination mitigation techniques need to be devised that will limit the effects of contamination to tolerable levels, for example: - Methods for effectively heating the structure/mirror after assembly - EVA suits that are much cleaner than contemporary models - Airlock techniques that have low contamination impact Structural dynamic modeling needs to be done to study - the impact on the structure of boost from LEO to L1 or L2 (Scenario 1) - the vibration stability of the autonomously deployed C-Clamp structure Effects of particle radiation from Van Allen belt on telescope instruments and electronics during boost from LEO to L1 or L2. What is the best mission scenario - considering space junk and gravity gradient at LEO - considering cost of designing, deploying and staffing Gateway for L1 - considering need to service both at initial deployment and later add-ons

19 As for the future, your task is not to foresee Chaos it, but to enable it Antoine de Saint-Exupery

20 Overview (1): Primer on Enabling the Future