Lunar Ranging Group LUNAR Team Gravitational Physics Lunar Physics Lunar Laser Ranging 12 April 2011 Pasadena, California

Overall Schedule University of Califonia, San Diego – Tom Murphy – Via Telephone Goddard Space Flight Centrer – Stephen Merkowitz / Alix Preston – Via Telephone University of Maryland, College Park – Doug Currie

Decadal Survey Submissions Astronomy and AstroPhysics Decadal Survey – Gravitational and Particle Physics Panel Report – Many Excellent Comments on the Value of LLR Planetary Sciences Decadal Survey – Lunar Geophysical Network Recommended for New Frontier Mission Would Place Four Retroreflectors on the Moon

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Topics UMd Talks Decadal Computer Simulations – Result Review Deployment & Roles GLXP – Candidates – Functions Deployment – Lander – Surface – Drilling Lifetime – Murphy – Sun Shade – Dust Bombardment Future Talks & Activities – Dust – ILRS Status and Suggestions Ground Stations – Tests at Frascati – NLSI Talk Demonstration

Conference Proceedings Currie, D. G.,, the LLRRA-21/LSSO Team & the MoonLIGHT/INFN-LNF Team 2010, “A Lunar Laser Ranging RetroReflector Array for the 21 st Century” 40 th Lunar and Planetary Science Conference, The Woodlands, TX 1 Currie, D. G., Zacny, K., 2010 Regolith Drilling for the Lunar Laser Ranging Retroreflector Array for the 21 st Century, LUNAR Workshop, Cambridge MA Currie, D. G., Zacny, K., the LLRRA-21/LSSO Team & the MoonLIGHT/INFN-LNF Team 2010 ”A Lunar Laser Ranging RetroReflector Array for the 21 st Century” Lunar Exploration Analysis Group Washington DC. Dell'Agnello, S., Delle Monache, G. O., Currie, D. G., et. All, G., & McElfresh D. “The Moon as a test body for General Relativity and new gravitational theories” presented at the conference European Planetary Science Congress 2010 (ESPC2010) at the Angelicum Centre – Pontifical University of Saint Thomas Aquinas, Rome, Italy. Dell’Agnello, S., Currie, D. G., Delle MonacheG. O., et al Cantone, C. Garattini, M. Martini, M. Intaglietta, N. Lops C., March, R, Tauraso, R, Bellettini G., Maiello, M, Berardi, S., Porcelli, L.; "Next Generation Lunar Laser Ranging and its GNSS Applications"; IEEE Aerospace Conference, Big Sky (MT), Peron, R.; Bellettini, G.; Berardi, S.; Boni, A.; Cantone, C.; Coradini, A.; Currie, D. G.; Dell'Agnello, S.; Delle Monache, G. O.;, et al. “Advanced instrumentation for Solar System gravitational physics” EGU General Assembly 2010, held 2-7 May, 2010 in Vienna, Austria, Currie, D. G., Delle Monache & G. O. Dell’Agnello, S “A Lunar Laser Retroreflector for the FOR the 21ST Century (LLRRA-21): Selenodesy, Science and Status” 2010 American Geophysical Union Fall Meeting San Francisco, CA Currie, D. G., Dell’Agnello, S. & Delle Monache, G. O “LUNAR LASER RANGING: FLIGHT HARDWARE SIMULATION, TESTING AND STATUS”. Lunar and Planetary Science Conference, The Woodlands, TX,

Talks, Colloquia and Public Presentations Talks at Scientific Conferences Currie, D. G., & the LLRRA-21 Teams 2011 “A LUNAR LASER RANGING RETRO-REFLECTOR ARRAY for the 21st CENTURY” 2 nd Lunar Laser Ranging Workshop, International Space Sciences Institute, Bern Switzerland Currie, D. G., & The LLRRA-21 Teams 2010 “A LUNAR LASER RANGING RETRO-REFLECTOR ARRAY for the 21 st CENTURY” LUNAR Workshop Boulder CO Currie, D. G., Dell’Agnello, S. & Delle Monache, G. O A Lunar Laser Ranging Retroreflector Array for the 21 st Century ISOT 2010 International Symposium on Optomechatronic Technologies, Toronto, CanadaISOT 2010 International Symposium on Optomechatronic Technologies, Toronto, Canada Currie, D. G., & the LLRRA-21 Teams 2011 “A LUNAR LASER RANGING RETRO-REFLECTOR ARRAY for the 21st CENTURY” 2 nd Lunar Laser Ranging Workshop, International Space Sciences Institute, Bern Switzerland Dell’Agnello, S.; Currie, D. G.; Delle Monache, G. O.; Lops, C.; M. Martini 2010 “LLRRA21/MoonLIGHT: a 2nd Generation Lunar Laser Ranging Array for Precision Gravity Tests and Lunar Science Measurements” at the Conference Global Lunar Conference – Beijing, China. Ddd 31 May-3 June 2010 talk Colloquia and Public Presentations Currie, D. G nd NLSI Commerce Virtual Lecture A LUNAR LASER RANGING RETROREFLECTOR FOR THE 21ST CENTURYA LUNAR LASER RANGING RETROREFLECTOR FOR THE 21ST CENTURY

Computer Simulations Problems – Commercial Software Issues – Computer Failures – 300 Million Beer’s Law Calculations for Each Computer simulation Objectives – End to End Simulation Technical Objectives – Selection of Thermal Coatings – Effects of Shorter Sun Shade GLXP Candidates for Size / Angular Tolerances Eclipse Effects – For LLRRA-21, not Apollo

Computer Simulations 500 Time Steps Over a Lunation HeatLoad3D – IDL – University of Maryland – Evaluates Solar Heat Loads in CCR at ~ a Million Nodes Thermal Desktop – Commercial - Cullimorgan and Ring Technologies – Combine CCR Heat Loads with Solar Inputs to Temperature at 1733 Nodes TempToPhase – IDL – University of Maryland – Converts Temperatures from thermal Desktop into Phase Errors Code V – Commercial - – Combines Thermal Phase Errors with TIR Phases and Effect of Offset Angles Analysis – IDL – University of Maryland – Converts Far Field Diffraction Patterns into Useful Operational Results

Frascati Testing Thermal Vacuum Tests – Optical Table for Far Field Diffraction Pattern – InfraRed Camera for Temperature Meaurements – Optical Simulator for “Sun” – Thermal Sensors on CCR Images of Chamber and CCR Face

Different Deployment Versions Single Shot Range Accuracy Current Single Shot Accuracy is ~20 mm If Mounted on Lander – Thermal Expansion of Lander – Heat Flux from Lander – Single Shot Accuracy of 1-3 millimeters If a Surface Deployment – Thermal Expansion of Regolith – Heat Flux from Lander – Sub-Millimeter Single Shot Accuracy If an Anchored Deployment – Anchored at ~1 meter depth – Better than 100 micron Single Shot Accuracy

Google Lunar X Prize Prize by Google Corporation for 30 M$ – Only Private Money for GLXP Objectives Can Be Government Money – For Other Objectives – Like LLRRA-21 Currently Working with: – Lunar Express, Hai Li – Astrobotics David Gump – Moon Express Bob Richards – NextGreatLeap Michael Joyce – Penn State University Miles Smith – FREDNETSean Casey Multiple Missions that May Be Successful – Achieve an Array of Retroreflectors

Deployment Lander

Surface Deployment

Anchored Deployment Astrobotics & Honeybee

Degradation of Laser Returns – Tom Murphy and APOLLO Station – Factor of 9.6 over 40 years Amelioration of Problem – Sun Shade Blocks Dust Deposition Block Micrometeorite Bombardment But What is the Real Reason for Degradation? – For Micrometeorite Bombardment – Test at Horanyi’s Dust Accelerator Lifetime of LLRRA-21

Signal Level for One LLRRA-21 Briefly – LLRRA-21 Signal ~ Equal to Apollo 15 Array – Therefore Can Works with Sub-Meter Telescopes Will Need to Upgrade of Laser, Timing Electronics McDonald at 0.67 meter Currently successfully Ranges to A15 – Long Life - Dust Issues Handled with SunShade More Precisely – IsoThermal – Station Angle LLRRA-21 Signal Return – LatitudeOffsets w.r.t. A15 – 45 Yes 78% – 45 No 58% – 00 Yes 88% – 00 No 71%

Future Objectives Schedule: >> Driven by the Google Lunar X Prize Launch – April/December 2013 i.e., Astrobotics – Need to Finalize the Design – Need to Attain Sufficient TRL to Obtain Funding i.e., T/V/O Test – Need to Fabricate/Test/Integrate Flight Hardware Simulations to Optimize Thermal Coatings – To Control Thermal Gradients and thus Signal – Optimize within Limits of Pracitical Coatings – Different Choices for Different GLXP Missions Interactions with GLXP Teams – Each has Different Physical & Organizational Structures – Therefore Each Requires Somewhat Different Thermal Design – Each Requires Different Emplacement Procedures

Future Talks & Activities Evaluate Dust Bombardment – Mihaly Horanyi – Dust Accelerator - Early May International Laser Ranging Service Meeting – Late May – Present Status of LLRRA-21 to Actual Ranging Groups – Collect Suggestions from Operators – Present What is Needed for Ground Stations for LLRRA-21 Thermal/Vacuum/Optical Tests at Frascati – Early June – TRL 6.5 -> TRL 7.0 NASA Lunar Science Institute – Mid July – Talk on LLRRA-21 Hardware and GLXP Mission Status – Report on Honeybee Grant on Pneumatic Drill for LLRRA-21 – Demonstration of Pneumatic Drilling Probably Mounted on Astrobotic Lander

Future Talks & Activities Sun Shade & Thermal Coatings – Simulate Various Thermal Coatings – Simulate Stepped Sun Shade – Fabricate Stepped Sun Shade – Thermal/Vacuum/Optical Test of Stepped Sun Shade – Simulate Elliptical Sun Shade Work with Google Lunar X Prize – Modify Nominal Design for Different Missions – Address Various Emplacement Strategies and Costs – Investigate Funding Routes for GLXP Flights Fabricate and T/V/O Test Big CCR with Offset Angles