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LAMP OverviewS.A. Stern
Lyman-Alpha Mapping Project (LAMP)
Lyman-Alpha Mapping Project (LAMP)
Alan Stern (SwRI, PI)
Dana Crider (Catholic U., CoI)Paul Feldman (JHU, CoI)Randy Gladstone (SwRI, CoI)Kurt Retherford (SwRI, DS)Joel Parker (SwRI, DPM)John Scherrer (SwRI, PM)Dave Slater (SwRI, PS)
LAMP OverviewS.A. Stern
Lyman-Alpha Mapping Project (LAMP)
The 2008 Lunar Reconnaissance Orbiter (LRO): A First Step in NASA’s Robotic Lunar
Exploration Program (RLEP)
Robotic Lunar Exploration ProgramRobotic Lunar Exploration Program
LAMP OverviewS.A. Stern
Lyman-Alpha Mapping Project (LAMP)
LRO Objectives
� Characterization of the lunar radiation environment, biological impacts, and potential mitigation.
� Develop a high resolution global, three dimensional geodetic grid of the Moon and provide the topography necessary for selecting future landing sites.
� Assess in detail the resources and environments of the Moon’s polar regions.
� High spatial resolution assessment of the Moon’s surface addressing elemental composition, mineralogy, and regolith characteristics
Congress to NASA: LRO should do basic lunar research as well.
LAMP OverviewS.A. Stern
Lyman-Alpha Mapping Project (LAMP)
2004 2005 2006 2007 2008 2009Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
1/5/05
LRO Mission Schedule
Task
LRO Mission Milestones
Mission Feasibility Definition
Payload Proposal Development
Payload Preliminary Design
System Definition
S/C &GDS/OPS Preliminary Design
Payload Design (Final)
Spacecraft Design (Final)
GDS/OPS Definition/ Design
Payload Fab/Assy/Test
S/C Fab/Assy/Bus Test
GDS/OPS DevelopmentImplemention & Test
Integration and Test
Launch Site Operations
Mission Operations
AO Sel.IARs IPDR
PDR
ConfirmationICDR
CDR
MORIPSR
PER
FOR/ORR
MRRPSR
LRR
LRO Launch
Network Acquisition
Payload complete (Final Delivery to I&T)
S/C complete (Final delivery to I&T)
GND Net Test Ready
Ship to KSC
LRO LAUNCH
AO Release
(1M Float)
S/C Bus
s/c subsys
GDS
s/c subsys
s/csubsys
Payload(1M Float)
(1M Float)
Ver. 0.3
(1M Float)
LRO Mission Schedule
LAMP OverviewS.A. Stern
Lyman-Alpha Mapping Project (LAMP)
LRO Implementation
� $400M cap (phases A-E) .� GSFC managed mission.� One year primary mission with
potential for up to 4 years extension.
Launched on a Delta II ELV into a direct lunar insertion trajectory (~4 days) designed and directed by GSFC Flight Dynamics
Baseline. Next step up is Atlas 5 or Delta IV Class.1485 kg3 stage w 9 Heavy
SRMsDelta 2925H
Target1285 kg3 stage w/ 9 SRMsDelta 2925
CommentP/L Capability
(C3 = -2 km2/s2)DescriptionELV
LRO propellant weight is
approximately 1:1 ratio to S/C dry
weight
LAMP OverviewS.A. Stern
Lyman-Alpha Mapping Project (LAMP)
LRO Lunar Orbit
� 50 km mean altitude� Controlled to ± 20 km� Approximately 90°
inclination� 113 min period� Up to 48 min lunar
occultation every orbit� From Earth,
interrupting tracking � From Sun, in
shadow
LAMP OverviewS.A. Stern
Lyman-Alpha Mapping Project (LAMP)
LRO’s Instrument Payload
� Lunar Exploration Neutron Detector (LEND). PI Dr. Igor Mitrofanov, ISR Moscow. LEND will map the flux of neutrons from the lunar surface to search for evidence of water ice and provide measurements of the space radiation environment.
� Lunar Orbiter Laser Altimeter (LOLA). PI Dr. David E. Smith, NASA GSFC. LOLA will determine the global topography of the lunar surface at high resolution, measure landing site slopes and search for polar ices in shadowed regions.
� Lunar Reconnaissance Orbiter Camera (LROC). PI Dr. Mark Robinson, Northwestern University. LROC will acquire targeted images of the lunar surface capable of resolving small-scale features that could be landing site hazards, as well as documenting changing illumination conditions.
� Diviner Lunar Radiometer Experiment. PI Professor David Paige, UCLA. Diviner will map the temperature of the entire lunar surface at 300 meter horizontal scales to identify cold-traps and potential ice deposits.
� Lyman-Alpha Mapping Project (LAMP). PI Dr. Alan Stern, SwRI. LAMP will observe the entire lunar surface in the far ultraviolet. LAMP will search for surface ices and frosts in the polar regions and provide images of permanently shadowed regions.
� Cosmic Ray Telescope for the Effects of Radiation (CRaTER). PI Professor Harlan Spence, Boston University. CRaTER will investigate the biological response to space radiation.
LAMP OverviewS.A. Stern
Lyman-Alpha Mapping Project (LAMP)
ALICE Build History
UVSCUVSC
BreadboardBreadboard
Development Phase
1993-1995Built and lab tested
RosettaRosetta
ALICEALICEIn flight for 10 months,
operating to specification1996-2001
New HorizonsNew Horizons
AliceAliceNow in S/C integration,Delivered Sep. 1, 2004
2001-2004
LROLRO
LAMPLAMPReady to start! 2005-2008
LAMP OverviewS.A. Stern
Lyman-Alpha Mapping Project (LAMP)
Data Quality
Pluto-Alice
Calibration Data
Rosetta-Alice
Flight Data
LAMP OverviewS.A. Stern
Lyman-Alpha Mapping Project (LAMP)
Water is expected at polar cold traps from solar wind protons [e.g., Crider & Vondrak 2000]
LAMP OverviewS.A. Stern
Lyman-Alpha Mapping Project (LAMP)
How can we see what’s inside the permanently shadowed craters near the poles?
LAMP OverviewS.A. Stern
Lyman-Alpha Mapping Project (LAMP)
The lunar FUV albedo is about 4% as measured by HUT [Henry et al., 1995], which agrees well with lab measurements of the lunar regolith [Wagner et al., 1987]
The Apollo 17 UVS showed that FUV albedo variations correlate with physical features [Fastieet al., 1973; Lucke et al., 1976]
LAMP OverviewS.A. Stern
Lyman-Alpha Mapping Project (LAMP)
Model reflected FUV spectral flux from the lunar night side. Assumes 300 R of ISM Lyα [Pryor et al., 1998] and composite sky spectrum of starlight [Mathis et al., 1983]
LAMP OverviewS.A. Stern
Lyman-Alpha Mapping Project (LAMP)
Why not use the ISM Lyα (plus UV starlight) to look at lunar night side and permanently shadowed regions?
LAMP OverviewS.A. Stern
Lyman-Alpha Mapping Project (LAMP)
LAMP:5.0 kg, 4.3 W0.2º×6.0º slit
1200-1800 Å bandpass<20 Å spectral resolution
LAMP OverviewS.A. Stern
Lyman-Alpha Mapping Project (LAMP)
Integration time as a function of latitude, after a 1-year mission at 50 km altitude, for 1-km and 5-km bins.
LAMP OverviewS.A. Stern
Lyman-Alpha Mapping Project (LAMP)
Expected LAMP SNR at Lyα after a 1-year LRO mission as a function of bin size for polar and mid-latitude regions (e.g., SNR>50 achieved in the polar regions at 0.5 km).
LAMP OverviewS.A. Stern
Lyman-Alpha Mapping Project (LAMP)
The difference between on-band and off-band ratios divided by the propagated errors defines our detection confidence (sigma), shown versus integration time. LAMP can detect water ice at concentrations as low as 1.5%, after about 2 weeks of elapsed mission time once LAMP observations begin for 5x5 km2 resolution bins, and after a year of elapsed observation time for 1x1 km2 bins during LRO’s one-year mission.
LAMP OverviewS.A. Stern
Lyman-Alpha Mapping Project (LAMP)
LAMP can also explore the tenuous lunar atmosphere by accumulating spectra where the surface is in shadow but most of the atmosphere is sunlit.
LAMP OverviewS.A. Stern
Lyman-Alpha Mapping Project (LAMP)
LAMP’s sensitivity to several possible atmospheric species at a few times in the LRO mission. Upper limits shown are from Feldman & Morrison [1991] and Parker et al. [1998].
LAMP OverviewS.A. Stern
Lyman-Alpha Mapping Project (LAMP)
LAMP Science/Measurement Summary
� LAMP will provide landform mapping (from Lyα albedos) at sub-km resolution in and around the permanently shadowed regions (PSRs) of the lunar surface.
� LAMP will be used to identify and localize exposed water frost in PSRs.
� LAMP will demonstrate the feasibility of using starlight and sky-glow for future surface mission applications.
� LAMP will detect (or better constrain) the abundances of several atmospheric species.
LAMP OverviewS.A. Stern
Lyman-Alpha Mapping Project (LAMP)
Development Phase Organizational Chart
R Black (SwRI)
LAMP OverviewS.A. Stern
Lyman-Alpha Mapping Project (LAMP)
LAMP Measurement Requirements Traceability
† LRO Objectives: Note A: “Identification of putative deposits of appreciable near-surface water ice in the polar cold traps.” Note B: “Landform-scale imaging of lunar surfaces in permanently shadowed regions.” Note C: “Technology demonstrations and system testing shall be performed to support development activities for future human lunar and Mars mission.” Note D: “Measure globally the composition, structure, and temporal variability of the lunar atmosphere.”
Atmosphere abundances of detected species, variability as a function of time. Species & variability detected to signals as faint as 0.001 Rayleighs. Sensitivity >10x better than prev. achieved; first-ever FUV lunar atmospheric line emission flux variability study.
Passband: 1000-1800 ÅSpectral Resolution: 40 Å or betterSpatial Resolution: N/A
Search for, detect and monitor the variability of H, Ar, and other atomic species.
2A. Assay the Lunar Atmosphere and Its Variability (LExSWG Final Report, p12, See Note D for quote)
Demonstration maps of albedo made at night without any sunlight or Earthshine. Albedo map resolutions down to 200 m & SNR=30/resolution element. No such demo has ever been undertaken.
Passband: 1200-1800 ÅSpectral Resolution: 100 Å or betterResolution: 5 km or better
Globally map lunar surface albedo at night.
1C. Sky-glow/Starlight Assisted PSR/Night Vision Demo (AO Section 1.2, LRO Measurement Sets, See Note C for quote)
Maps of all PSRs, even where there is no reflected Sun, or Earthshine. Albedo maps with resolutions down to 500 m and SNR=50/resolution element. No maps of albedo in PSRs exist.
Passband: 1200-1800 ÅSpectral Resolution: 600 Å or betterSpatial Resolution: 1 km or better
Map the albedos of the PSRs using UV sky-glow and starlight as the light source.
1B. Collect Landform-Scale Mapping in All Areas of the PSRs (AO Section 2.0, LRO MeasuremtSets, See Note B for quote)
Water-frost concentration maps of the lunar polar regions. Mapping resolutions as good as 3 km for frost abundances down to 1.5%. No maps of exposed polar H2O abundance now exist.
Passband: 1200-1800 ÅSpectral Resolution: 70 Å or betterSpatial Resolution: 10 km or better
Map abundance of exposed water frost to abundances levels of 4% or lower using its UV absorption sig.
1A. Identify & Localize ExposedWater Frost in All Areas of Permanently Shadowed Regions (PSRs)(AO Section 2.0, LRO Measurement Sets: See Note A for quote)
LAMP Data Products, Expected Results, Improvement Over Current
Knowledge
LAMP Instrument Minimum Requirements/
Dataset Min. Requirements
LAMP Observation Requirements
LAMP Measurement Objective (Traceability of the Objective)†
LAMP OverviewS.A. Stern
Lyman-Alpha Mapping Project (LAMP)
LAMP Minimum Required & Expected Performance
Nyquist sampled: 0.64 degNyquist sampled: 1 deg or less`Spatial Resolution (PSF)
Notes: (1) LAMP’s minimum performance requirements were derived to satisfy the Group 1 Instrument and Dataset Requirements
Same.Continuous, time-tagged pixel list with “ping-pong” memory fill.
Detector Output
Total array: 20 counts/sec (Rosetta-ALICE value; Pluto-ALICE is 2.5 counts/sec on ground)
Total array: <50 counts/secDetector Global Background Rate
09 kHz (~15% deadtime loss)38 kHz (~50% deadtime loss)
03 kHz or greater (~15% deadtime loss)15 kHz or greater (~50% deadtime loss)
Detector Dead-Time Metrics
<10-6 at 7 deg off-boresight<10-5 at 7 deg off-boresightStray Light Rejection
±14% (1σ)±30% (1σ) or lessDetector Flat Field Uniformity
30 Å FWHM averaged across passband (Note: Pluto-ALICE best was15 Å, owing to its slit)
40 Å FWHM or less, averaged across passband
Filled Slit Spectral Resolution
<5 Å FWHM across passband<20 Å FWHM across passbandSpectral Resolution (PSF)
0.2x6 deg(Note: Pluto-Alice slit was 0.1x4 deg + 2x2 deg)
0.2x6 degSlit FOV
2X effective area figure (Note: Pluto-ALICE was 0.3 cm2, peaking 1000 Å, but it was optimized differently)
0.4 cm2 at peak at 1250 Å(See effective area figure)
Effective Area
520-1870 Å1200-1800 ÅPassband
LAMP Expected Performance (Same As Actual Pluto-ALICE Delivered
Performance, Except If Noted)
LAMP Minimum Performance Requirement1
Attribute
(Expected Performance Is the Same As Delivered Pluto-ALICE Performance, Except As Noted)