Lunar Flashlight Mapping Lunar Surface Volatiles Using a Cubesat
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Lunar Flashlight Mapping Lunar Surface Volatiles Using a CubeSat Dr. Barbara Cohen Lunar Flashlight PI/ Measurement Lead NASA Marshall Space FISO Telecon Flight Center 4/22/15 Lunar Flashlight: a secondary payload • 19 NASA center-led concepts were evaluated and 3 were down-selected by the Advanced Exploration Systems (AES) program • Primary selection criteria: – Relevance to Space Exploration Strategic Knowledge Gaps (SKGs) – Synergistic use of previously demonstrated technologies – Life-cycle cost and optimal use of available civil servant workforce • Other secondary payloads may be added (11 total) 2 Space Launch System (SLS) EM-1 (2018) • SLS Block 1 (70 mT) • Uncrewed circumlunar flight, duration 7 days, free- return trajectory • Demonstrate integrated systems, high-speed entry (11 km/s) EM-2 (2021-2022) • SLS Block 1 (70 mT) • Crewed lunar orbit mission (?) • Mission duration 10-14 days 3 Secondary payloads on EM-1 • Room for 11 6U cubesats on standard deployer • Secondary payloads will be integrated on the MPCV stage adapter (MSA) on the SLS upper stage MPCV • Secondary payloads will MPCV Stage Adapter (MSA) MSA be deployed on a trans- Diaphragm lunar trajectory after the Launch Vehicle Adapter upper stage disposal (LVSA) LVSA maneuver Diaphragm Core Stage Block 10001 4 Near Earth Asteroid Scout GOALS Marshall Space Flight Center/Jet Propulsion Characterize one Lab/LaRC/JSC/GSFC/NASA candidate NEA with an imager to address key One of three 6U Strategic Knowledge Cubesats sponsored Gaps (SKGs) by Advanced Demonstrates low cost Exploration System, capability for HEOMD for Joint Robotic Program NEA detection and to fly on SLS EM-1 reconnaissance Measurements: NEA volume, spectral type, spin and orbital properties, address key physical and regolith mechanical SKGs Biosentinel: DNA Damage-and-Repair Experiment Beyond Low Earth Orbit • What: Yeast radiation biosensor measures DNA damage caused by space radiation: specifically, double strand breaks (DSBs) • Why: Space radiation’s unique spectrum cannot be reproduced on Earth – Various high-energy particles/energy spectra; omnidirectional; continuous; low flux – Health risk for humans over long durations beyond LEO • How: Before launch, engineered S. cerevisiae cells (brewer’s yeast) are dried & placed in arrays of microwells – In space, a group of wells is rehydrated every few weeks – Cells remain dormant until growth is activated by a DSB + gene repair – Yeast repair mechanisms in common with human cells; well studied in space 6 Why look for water ice? • The Moon is highly depleted in volatile compounds, especially water • Humans exploring the Moon will need water: – Option 1: Carry it there. ↵ expensive (at $10K/lb, 1 gal H2O=$80K) – Option 2: Use water that may be there already. ↵ “live off the land” • Can mine O2 from minerals and H from solar wind implantation, however, this is very energy intensive • Life would be much easier and cheaper if we could use H2O from the Moon At the surface or near surface In “operationally useful” quantities 7 Water on the Moon Volcanic glass from the Moon Mineralogy Mapper (M3), Multiple ground-based and Apollo 15 landing site and EPOXI and Cassini instruments space assets (Clementine, apatite grains from the Apollo found trace H2O and OH on the Lunar Prospector, LRO, samples and lunar meteorites lunar surface near the poles, as a LCROSS, Kaguya) have contain trace amounts of monolayer on lunar dust grains or suggested water ice resides water (5-50 ppm) as part of bound into the mineral structures of in permanently-shadowed the mineral structures (e.g., surface materials (Pieters et al., regions (PSRs) at the lunar Saal et al. 2008; McCubbin et 2009; Sunshine et al., 2009; Clark, north and south poles. Too al. 2010, 2013). Too little. 2009). Too little. deep. 8 Water ice frost in PSRs? • Locations where Diviner measures the • Ultraviolet albedo data from coldest year-round temperatures also LAMP also show evidence for show high albedo in LOLA at 1.064 µm, water ice at the lunar surface, consistent with water frost but are not yet definitive 9 What we need to know Lunar Strategic Knowledge Gaps I. Understand the lunar resource potential D. Composition/quantity/distribution/form of water/H species and other volatiles associated with lunar cold traps. Narrative: Required “ground truth” in-situ measurement within permanently shadowed lunar craters or other sites identified using LRO data. Technology development required for operating in extreme environments. Enables prospecting of lunar resources and ISRU. Relevant to Planetary Science Decadal survey. • Lunar Flashlight will illuminate permanently-shadowed and detect water ice absorption bands in the near-infrared – Measurement goal • By repeating this measurement over multiple points, Lunar Flashlight will create a map of surficial ice concentration that can be correlated to previous mission data and used to guide future missions – Mapping goal 10 LF Mission Overview • 6U Cubesat (form factor 10 cm x 20 cm x 30 cm) • ~85 m2 sail reflects sunlight into permanently shadowed regions • IR 4-band point spectrometer measures H2O absorption & continuum • Teaming: JPL & MSFC – S/C, Payload, Mission Design & Nav: JPL – Propulsion: MSFC – I&T, Ops: JPL & MSFC not to scale – Science: MSFC, JPL, APL, UCLA • Leverages: • SLS Secondary: EM1 – Solar sail development expertise (NanoSail-D, • Schedule: Launch 2018 • Arrival Date: 2019 Sunjammer, LightSail-1) • Duration: 2 years – CubeSat developments and standards (INSPIRE, • MCR/SRR: August 2014 university & industry experience) – Synergies with NEA Scout (bus, solar sail, comm, I&T, ops) 11 LF Flight System overview • Lunar Flashlight: Custom spectrometer Payload • NEA Scout: Heritage JPL MSL/Mars 2020 imager (400-900 nm) Star Tracker ! Rad Tolerant C&DH • “6U” CubeSat form factor (~10x20x30 cm) (Blue Canyon) LGA Mechanical (JPL) (JPL) • <12 kg total launch mass & Structure LF Spectrometer • Modular flight system concept (JPL) • ~85 m2 aluminized Kapton solar sail (based Propulsion on NanoSail-D2) EPS (TBD) Avionics • Radiation tolerant LEON3-FT architecture • Simple deployable solar arrays with UTJ 18650 Lithium BaMeries (SDL/Panasonic) Electrical GaAs cells (~35 W at 1 AU solar distance) Power • 6.8 Ah Battery (3s2p 18650 Lithium Cells) Iris 2.0 Transponder System • 10.5-12.3 V unregulated, 5 V/3.5 V (JPL) regulated • JPL Iris 2.0 X-Band Transponder; 1 W RF, supports doppler, ranging, and D-DOR Telecom • 2 pairs of INSPIRE-heritage LGAs (RX/TX) TRAC Boom Assy x2 (MSFC) RWA x4 (Blue • Lunar Flashlight: ~500 bps to 34m DSN at Canyon) all times. • 15 mNm-s (x3) & 100 mNm-s RWAs • Zero-momentum slow spin during cruise Attitude • VACCO R-236fa (refrigerant gas) RCS Control Solar Sail x2 - Stowed system System (MSFC) Solar Panels x4 (MMA) • Nano StarTracker, Coarse Sun Sensors & MEMS IMU for attitude determination RCS (VACCO) 12 Solar Sail Development History 200m2 IKAROS JAXA 32m2 80m2 NEA Scout Lightsail-1 ~1200m2 NASA TDM Planetary (STMD) Sunjammer Society 3.5-m NanoSail-D2 (2010) 80m2 Lunar Flashlight 20-m ground demo (2005) 13 LF Concept of Operations (example) Moon • ~1.35 million km max Earth Disposal distance Science passes • Sail Lunar Capture • De-tumble deployment Spiraling down • ~8m/s dV to • Target second target first lunar lunar fly-by fly-by Lunar Fly-by 3 Cruise Lunar Fly-by 2 • ~1 year spiraling Separation phase around from SLS the moon Lunar Fly-by 1 Instrument Sail deployment Calibration & EPO Activity Calibration (Earthflash) (Jupiter) L+4.5 days L+2 month L+2.5 months L+6 months L+20months L+21.5 months Earth Mission Duration < 2 years Mission Lifetime < 2 years Not to scale 14 15 LF Goals and Objectives Lunar Flashlight Level 1 NASA Goals Measurement Objectives Requirements Human Exploration Strategic Knowledge Gaps for the “Moon Objective 1 (measurement) First” Human Exploration Scenario LF shall measure the I. Understand the lunar resource potential abundance of lunar volatiles ID. Composition/quantity/distribution/form present at levels ≥0.5 wt% in of water/H species and other volatiles the lunar regolith with a associated with lunar cold traps Lunar Flashlight shall have the precision of ±50% or better capability to address a key Strategic Science Knowledge Gap at the Moon Planetary Science Decadal Survey, Terrestrial Planets Characterize Planetary Surfaces to Objective 2 (mapping) Understand How They Are Modified by LF shall map the distribution Geologic Processes of exposed water ice with 1-2 • What are the compositions, distributions, km resolution within the and sources of planetary polar deposits? permanently shadowed regions at the lunar south pole Lunar Flashlight shall be in a 6U Technology cubesat form factor compatible with a Demonstrate low-cost reconnaissance NASA provided cubesat deployer for capability for HEOMD through the use of launch on a NASA provided launch innovative solutions vehicle 16 Objective 1: Measurement 0.6$ A B C D 0.55$ 0.5$ 0.45$ ice$ 0.5wt%$ • Reflectance 0.4$ 1.0wt%$ spectroscopy is the Reflectance( 2.0wt%$ 0.35$ standard technique for 5.0wt%$ identifying molecular 0.3$ 10wt%$ “fingerprints” from a 20wt%$ 0.25$ 40wt%$ distance 80wt%$ 0.2$ regolith$ • Measure absorption and 0.5$ 1$ 1.5$ 2$ 2.5$ continuum to understand Wavelength((microns)( ice abundance 17 Objective 1: Measurement 1.5 H2O ice, r = 10 micron 1.01 CO2 ice, r = 10 micron 1.005 CO2 ice 1.4 0.988 Mixtures 1 1.3 0.986 0.995 C/D 0.99 1.2 C/D C/D 0.984 0.985 Dry 1.1 0.899 A/B Water 0.98 regolith ice Mixtures 1 Dry 0.975 regolith 0.9