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LAMP OverviewS.A. Stern

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)



The 2008 Lunar Reconnaissance Orbiter (LRO): A First Step in NASA’s Robotic Lunar

Exploration Program (RLEP)

Robotic Lunar Exploration ProgramRobotic Lunar Exploration Program



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.



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



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



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



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.



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



New Horizons Alice



Data Quality

Pluto-Alice

Calibration Data

Rosetta-Alice

Flight Data



Water is expected at polar cold traps from solar wind protons [e.g., Crider & Vondrak 2000]



How can we see what’s inside the permanently shadowed craters near the poles?



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]



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]



Why not use the ISM Lyα (plus UV starlight) to look at lunar night side and permanently shadowed regions?



LAMP:5.0 kg, 4.3 W0.2º×6.0º slit

1200-1800 Å bandpass<20 Å spectral resolution



New Horizons Alice



Integration time as a function of latitude, after a 1-year mission at 50 km altitude, for 1-km and 5-km bins.



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).



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 can also explore the tenuous lunar atmosphere by accumulating spectra where the surface is in shadow but most of the atmosphere is sunlit.



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 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.



Development Phase Organizational Chart

R Black (SwRI)



Backup Slides



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 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)

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