SCF Lab @ LNF

SCF-Test GPS flight array by USSR" CCR Technology deployed on GLONASS, GPS, GIOVE. We have de-qualified it with SCF-Testing. It is not and will not be u...

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SCF_Lab @ LNF! R&D and Services on laser retroreflector-based Geometrodynamics for Gravity, GNSS, GMES, EO, …!

SCF_Lab" Satellite/Lunar/GNSS! laser ranging and altimetry Characterization Facilities Laboratory! Simone Dell’Agnello for the SCF_Lab Team Italian National Institute for Nuclear Physics, Laboratori Nazionali di Frascati (INFN-LNF), Via Enrico Fermi 40, Frascati (Rome), 00044, Italy

INFN-Space/3, Frascati, September 19, 2012!

SCF_Lab Team. Acknowledgments.! INFN-LNF!

Students!

S. Dell’Agnello,! F. Piergentili, G. Capotorto,! G. Delle Monache,! M. Marra, V. Maddaluno! R. Vittori (MAE, Defense, …)! G. Bianco (ASI-CGS),! We acknowledge important! D. Currie (USA, U. of Maryland)! support/contracts from/with:! C. Cantone,! ASI,! A. Boni, C. Lops,! ESA & Galileo,! M. Maiello, S. Berardi,! Italian Ministry of Defense/Air Force,! G. Patrizi, M. Martini! G. Bellettini, R. Tauraso! ISRO! R. March,! N. Intaglietta, M. Tibuzzi,! E. Ciocci, S. Contessa! L. Salvatori, L. Palandara! M. Lobello, A. Stecchi,! E. Bernieri! S. Dell’Agnello (INFN-LNF) et al!

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Acronyms and definitions! 1.  2.  3.  4.  5.  6. 

7.  8.  9.  10.  11.  12.  13. 

ASI: Agenzia Spaziale Italiana! BT: Break Through! CCR: Cube Corner Retroreflector ! EO = Earth Observation! ESA: European Space Agency! ETRUSCO: Extra Terrestrial Ranging to Unified Satellite Constellation! FFDP: Far Field Diffraction Pattern! FOC: Full Orbit Capability! GCO: GNSS Critical half Orbit! GMES = Global Monitoring for Environment and Security! GNSS : Global Navigation Satellite System! GPS: Global Positioning System! GRA: GNSS Retroreflector Arrays!

S. Dell’Agnello (INFN-LNF) et al!

13.  14.  15.  16.  17.  18.  19.  20.  21.  22.  23.  24.  25.  26. 

GTRF: Galileo Terrestrial Reference Frame! ILRS: International Laser Ranging Service! IOV: In Orbit Validation! IPR: Intellectual Property Rights! ITRF: International Terrestrial Reference Frame! ITRS: International Terrestrial Reference System! KPI: Key Performance Indicator! OCS: Optical Cross Section! LAGEOS: LAser GEOdynamics Satellite! SCF: Satellite/lunar/GNSS laser ranging and altimetry Characterization Facility! SCF-G: Satellite laser ranging Characterization Facility optimized for GNSS! SLR: Satellite Laser Ranging! TIR: Total Internal Reflection! WI: Wavefront Interferogram!

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GNSS, Gravitation, Space geodesy. ILRS" LEO, GNSS, GEO, Moon! Int. Terrestrial Reference Frame (ITRF)!

SLR constellation!

  Geocenter from SLR (LAGEOS)!   Scale from SLR (LAGEOS) and VLBI!   Orientation (wrt ICFR) from VLBI!   ITRF distribution w/GNSS!   DORIS, …! LAGEOS"

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SCF_Lab @INFN-LNF! Two world-unique OGSE (Optical Ground Support Equipment) facilities in a clean room to characterize the space segment of laser ranging altimetry. In ‘INFN jargon’: “test beam of laser retroreflector detectors”! SCF for SLR/LLR/ GNSS/ Altimetry! (RD-1, RD-2)!

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SCF-G for GNSS (RD-10)! !

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SCF_Lab @ LNF! Two solar simulators, two optical Far Field Diffraction Pattern optical tables, one Wavefront Fizeau Interferometer (WFI, capable of linear and circular polarization), Class 10000 / ISO 7 clean room!

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The SCF-Test (background IP of INFN)! J. Adv. Space Res. 47 (2011) 822–842!

S. Dell’Agnello (INFN-LNF) et al!

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SCF-Test/Revision-ETRUSCO-2 (ASI-INFN)! •  Laboratory-simulated space conditions. Concurrent/integrated:! –  –  –  –  –  – 

Dark/cold/vacuum! Sun AM0 simulators (2) and Earth IR simulator! Non-invasive IR and contact thermometry! Laser interrogation and sun perturbation at varying angles! Payload thermal control! Payload roto-translations!

•  Deliverables / Retroreflector Key Performance Indicators (KPIs)! –  Thermal behavior (τCCR, thermal relaxation time)! –  Optical response: Far Field Diffraction Patter, (near-field) Wavefront Fizeau Interferogram!

•  Beware: reduced, partial, incomplete tests (compared to the full space environment) can be very misleading (either optimistic or pessimistic)! S. Dell’Agnello (INFN-LNF) et al!

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Space Flagships: Galileo, GMES …! •  Galileo, ETRUSCO/ETRUSCO-2 (INFN-ASI)! –  EU Flagship Space Program n. 1 !

•  GMES, Global Monitoring for Environment & Security! – 

EU Flagship Space Program n. 2!

•  ETRUSCO-GMES (CSN5 R&D), with external contracts:! –  ETRUSCO-IOV: SCF-Test for Galileo IOV! –  ETRUSCO-IRNSS : SCF-Test for ‘Indian Galileo’ (GNSS)! –  G-CALIMES: Laser-based Unification of Galileo and Italian constellations for radar mapping of Earth surface! •  Cosmo-SkyMed (CSK) & Cosmo Second Generation (CSG)! S. Dell’Agnello (INFN-LNF) et al!

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SCF-Test GPS flight array by USSR" CCR Technology deployed on GLONASS, GPS, GIOVE. We have de-qualified it with SCF-Testing. It is not and will not be used anymore for GNSS, not even on GLONASS!

Third and last ever made for GPS. On loan from Univ. of Maryland to SCF_Lab! ~19 x 24 cm2,~1.3 Kg,! 32 CCRs!

S. Dell’Agnello (INFN-LNF) et al!

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GPS flight model optical cross section at 532 nm in air/isothermal conditions vs. velocity aberration" Measurement in absolute m2, µrad units.! Below specs by factor > 5 at 20-20 µrad, because array is small and inefficient! ! To my knowledge this is the only measured,! published optical cross section for GNSS! S. Dell’Agnello (INFN-LNF) et al!

vs. azimuth at fixed! velocity aberrations!

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SCF-Test of GPS flight model! TOUTER CCR FACE(K) vs t(s)"

Sun Simulator ON"

Factor ~7 reduction of laser return

Sun on:! laser return! (FFDP)! severely degraded!

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AM0 Sun simulator!

Sun Simulator OFF"

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ILRS!

Earth shadow!

Sun off:! laser return! (FFDP) peaks restored!

Satellite! with CCR!

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SCF-Test of GLONASS/GIOVE CCR! Sun on: laser return (FFDP)! Peaks severely degraded; distpeaks~1km! FFDP on CCD!

Sun Simulator ON"

Sun Simulator OFF"

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Factor ~7 reduction of FFDP AM0 Sun simulator!

Sun off: FFDP peaks restored; dpeaks~0.5 km! FFDP on CCD!

Earth shadow!

ILRS!

Satellite! with CCR!

TOUTER CCR FACE(K) vs t (sec)" S. Dell’Agnello (INFN-LNF) et al!

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Making optical SCF movies" (of laser return)! SCF-Test of " GLONASS, " GIOVE! TOUTER CCR FACE(K)" vs. time (sec)"

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SCF-Test of LAGEOS Sector of NASA-GSFC!

LAGEOS is the ILRS reference payload standard. ! Clockwise:! ! SCF and its Solar, IR and Laser windows;! IR photo of the Sector; laser illuminating one CCR inside the SCF; Sector at GSFC!

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LAGEOS optical response in air/isothermal conditions! 532 nm!

Red: CodeV simulation! (solid red is nominal curve)! Blue: measurements! To be compared to solid red!

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SCF-Test of LAGEOS Sector! LAGEOS is the ILRS reference payload standard:! 1) Laser response: modest degradation unlike GPS, GLO, GIOVE!

FFDP=100%!

2) Thermal behavior: measured thermal constants in various conditions. This database of constants useful for POD.!

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Making thermal SCF movies! SCF-Test of LAGEOS Sector:! IR movie of Sector moving from AM0 (sun simulator) window to laser window at 90o. IR camera is in between!

For ESA s test of Galileo reflectors, rotation accomplished in ~1-2 sec!

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Unique new tool: SCF-Test/Revision-IR! Space characterization of retroreflectors for laser ranging/altimetry at 1064nm from orbiters of the Moon (like LRO), Mars-Phobos-Deimos (GETEMME proposed), icy/rocky moons of Jupiter and Saturn (future Europa and Encelado landers).!

Science: fundamental gravity, planetary science, space exploration!

GETEMME:" Gravity, Einstein’s! Theory, and Exploration of Martian Moons’! Environment!

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Payload for planetary laser ranging/altimetry! •  INRRI: INstrument for landing-Roving laser ranging/altimetry Retroreflector Investigations! •  Passive, ~25 gr, ~60 mm×20 mm! •  Proposed dor Landers/Rovers on moons and (Exo)Mars 2018!

•  ExoMars: approved strategic cornerstone ESA-Roskosmos mission!

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INRRIs at: Moon; Mars; Jupiter & Saturn moons! Cartoon not to scale!

Laser! ranging!

Laser altimeter!

Planet/asteroid/ icy-rocky moon" rover at EoL !

Petit Poucet rover:! arm, CCR, camera …! ! ! 1064! nm!

Planet/asteroid/icy-rocky moon"

VIS!

camera!

Crater or canyon or iced sea? !

rock! or iceberg!

•  From orbiters selenolocate activity of rover thanks to reflectors! –  LRO, ExoMars, GETEMME!

•  INRRI networks! •  Also on far side of Earth’s Moon! INFN-Space/3, Frascati, 19/09/13!

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ETRUSCO-2: ASI-INFN Program for GNSS (2010-2013)" [RD-10]!

Optimized for Galileo and GPS-3!

PI:" S. Dell’Agnello" " Co-PIs:" R. Vittori, ESA" G. Bianco, ASI"

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SCF-Tested retroreflector arrays:" LAGEOS model, GPS flight reflector array" modern GNSS array for Galileo/GPS3 by INFN-ASI!

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For ASI did industrial optical acceptance test of LARES (in-air nominal specs, NO SCF-TEST!)! S. Dell’Agnello (INFN-LNF) et al!

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Global Navigation Satellite System (GNSS):" ~100 satellites with laser retroreflectors (CCRs)" Indian IRNSS: 7+4 regional satellites!

European Galileo:! 30 satellites !

Japanese QZSS: 3 regional satellites!

US GPS: 24 global satellites!

Chinese COMPASS: 20 global and 5 regional satellites! Russian GLONASS: 24 global satellites! S. Dell’Agnello (INFN-LNF) et al!

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Galileo IOV (In-Orbit validation) IOV1, IOV2 launched on Oct. 2011!

IOV3, IOV4 launched on Oct. 2012!

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Galileo implementation plan!

2 IOV satellites launched Oct. 2011! 2 launched Oct. 2012!

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Galileo Services! • Open Service: the Galileo navigational! signal will be accessible by the general! public free of charge, providing improved! global positioning. It s the only open GNSS ! ! • Public Regulated Service: two encrypted! signals with controlled access for specific! users such as governmental bodies.! ! • Search and Rescue Service: Galileo! will contribute to the international! Cospas–Sarsat system for search and rescue.! A distress signal will be relayed to the Rescue Coordination Centre and Galileo will inform the user that their situation has been detected.! ! • Safety-of-Life Service: standard already available for aviation (ICAO standard) thanks! to EGNOS, Galileo will further improve! the service performance.! ! • Commercial Service: Galileo will provide a signal for high data throughput and highly! accurate authenticated data (time synchronization), particularly interesting for professional users.! S. Dell’Agnello (INFN-LNF) et al!

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Why Europe needs Galileo?! Galileo is a strategic program:! •  The European Commission (EC) estimates that 6-7% of European GDP, around 800 billion by value, is dependent on satellite navigation.! •  The EC and European Space Agency (ESA) joined forces to build Galileo: Europe s independence is the chief reason.! •  By being inter-operable with GPS and GLONASS, Galileo will allow positions to be determined accurately for most places on Earth, even in high rise cities where buildings obscure signals from satellites low on the horizon.! •  Galileo will achieve better coverage at high latitudes. ! •  Europe will be able to exploit the opportunities provided by satellite navigation to the full extent.!

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First 4 Galileo IOV satellites! 1: L-band antenna Transmits the navigation signals in the L-band." 2: Search & rescue antenna" 3: C-band antenna" 4: Two S-band antennas" 5: Infrared Earth sensors" 6: visible light Sun sensors" 7: Laser retroreflector" 8: Space radiators" 9: Passive hydrogen maser clock" " Mass: about 700 kg" Size with solar wings stowed: 3.02 x 1.58 x 1.59 m" Size with solar wings deployed: 2.74 x 14.5 x 1.59 m" Design life: more than 12 years" Available power: 1420 W (sunlight) / 1355 W (eclipse)"

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Internal anatomy of the Galileo IOV satellite! •  • 

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•  •  •  •  •  • 

Rubidium clock: an atomic clock based on a different technology, ensuring redundancy to the masers. It is accurate to within 1.8 nanoseconds over 12 hours.! Clock monitoring and control unit: provides the interface between the four clocks and the navigation signal generator unit. It also ensures that the frequencies produced by the master clock and active spare are in phase, so that the spare can take over instantly should the master clock fail.! Navigation signal generator unit: generates the navigation signals using input from the clock monitoring and control unit and the uplinked navigation and integrity data from the C-band antenna. The navigation signals are converted to L-band for broadcast to users.! Laser retroreflector array: absolute/accurate positioning of the satellite.! Gyroscopes: measure the rotation of the satellite.! Reaction wheels: control the rotation of the satellite. When they spin, so does the satellite, in the opposite direction. The satellite rotates twice per orbit to allow the solar wings to face the Sun s rays.! Magneto-torquer: modifies the speed of rotation of the reaction wheels by introducing a magnetism-based torque (turning force) in the opposite direction.! Power conditioning and distribution unit: regulates and controls power from the solar array and batteries for distribution to all the satellite s subsystems and payload.! Onboard computer: controls the satellite platform and payload.!

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SCF-Test of Galileo Critical half-Orbit (GCO)! Earth! shadow!

Sunrise-Eclipse-Sunset probes critical features of the thermal and optical behavior of the CCR

Galileo orbit: •  Altitude = 23222 km •  Period ~ 14 hr, shadow ~ 1hr GCO conceptual drawing not to scale!

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Galileo reflector temperature measurements! Measured temperat. vs. time (& sun inclination): -

2 probes on CCR housing 2 probes on Al housing 1 probe on the back-plate IR camera thermograms of the outer CCR face Bottom CCR housing Top CCR housing Bottom Al housing Top Al housing Back plate +++!CCR face

Note the very large temperature excursion, >100 K!

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Galileo laser return intensity measurement" at 24 μrad velocity aberration !

~ -13o

~13o

FFDP=100%!

Earth! Sunrise & thermal BT!

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Sunset & optical BT!

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Recognition of Italian work for Galileo by ESA on website of International Laser Ranging Service!

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INFN press release: IOV launch & SCF_Lab!

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ETRUSCO-IOV Contract (ESA-Galileo-INFN): SCF-Test of IOV reflectors (CCRs)! Galileo! 1 CCR !

Reduced array 7 CCRs! !

Full-size array 84 CCRs!

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ETRUSCO-IOV Contract (1 year)! •  Kick-off meeting on October 15, 2013! •  Build 7-CCR array, test 1-by-1 & whole array! •  Loan of flight 84-CCR array for Galileo IOV, to be SCFTested with additional Contract! •  Draft ESA-INFN MoU for access to SCF_LAB R&D! –  ESA for Galileo / Galileo-V2 / EGNOS-V2! –  ESA contractors for any mission with retroreflectors! S. Dell’Agnello (INFN-LNF) et al!

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European Space Technology Master Plan" (ESTMP)! Ultimate goal: publish SCF and SCF-Test in ESTMP, as! INFN-CSN5 technology! -  ESTMP analogous of the Particle Data Book (PDG) in fundamental and particle physics! -  SCF/SCF-Test proposed for VQR as INFN technological product!

Galileo! IOV!

With co-funding INFN keeps IPR! -  Potential patents and royalties are Agency/ contract dependent! S. Dell’Agnello (INFN-LNF) et al!

CCRs! INFN-Space/3, Frascati, 19/09/13!

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ETRUSCOIRNSS:" Noncompetitive Invitation to Tender on SCF-Test of retroreflectors of the Indian GNSS (IRNSS) by the Indian Space Research Organization (ISRO)! S. Dell’Agnello (INFN-LNF) et al!

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ISRO-INFN Contract for SCF-Test of IRNSS" Ongoing activity!

Laser Reflector Array!

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G-CALIMES: Defense-INFN Contract! •  Continuation, enhancement and major extension of ETRUSCO program with development of fundamental geometrodynamics networks in Earth and Space for! –  Galileo, and other GNSS! –  GMES: Global Monitoring for Environment and Security! –  Galileo-Cosmo-skymed Absolute Laser Intercalibration!

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GMES: from ESA Bulletin Feb. 2012

Monitoring of Environment with Galileo (“SatNav”) and Synthetic Aperture Radar (SAR)! SAR: Italy’s CosmoSkyMed (CSK) and ESA’s Sentinel-1!

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ETRUSCO-GMES (CSN5, co-funding of G-CALIMES) Unify observations of Galileo & Cosmo constellations, through absolute laser inter-calibrations!

From ESA Bulletin Feb. 2012!

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GMES: from ESA Bulletin Feb. 2012!

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Another application and EU flagship programme: GMES - Observing our planet for a safer world Managing natural resources and biodiversity, observing the state of the oceans, monitoring the chemical composition of our atmosphere: all depend on accurate information delivered in time to make a difference. The

European initiative for the Global Monitoring for Environment and Security (GMES) will provide data to help deal with a range of disparate issues including climate change and border surveillance. Land, sea and atmosphere - each will be observed through GMES, helping to make our lives safer. ! The purpose of GMES is to deliver information on environment and security which correspond to identified user needs

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SCF_Lab @ LNF! LNF infrastructure for! R&D and industrial Services on laser retroreflector-based Geometrodynamics for Gravity, GNSS, GMES, EO, …!

SCF_Lab" Satellite/Lunar/GNSS! laser ranging and altimetry Characterization Facilities Laboratory! S. Dell’Agnello (INFN-LNF) et al!

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Main Reference Documents! •  •  •  •  • 

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[RD-1] Dell’Agnello, S., et al, Creation of the new industry-standard space test of laser retroreflectors for the GNSS and LAGEOS, J. Adv. Space Res. 47 (2011) 822–842. [RD-2] P. Willis, Preface, Scientific applications of Galileo and other Global Navigation Satellite Systems (II), J. Adv. Space Res., 47 (2011) 769. [RD-3] D. Currie, S. Dell’Agnello, G. Delle Monache, A Lunar Laser Ranging Array for the 21st Century, Acta Astron. 68 (2011) 667-680. [RD-4] Dell’Agnello, S., et al, Fundamental physics and absolute positioning metrology with the MAGIA lunar orbiter, Exp Astron, October 2011, Volume 32, Issue 1, pp 19-35 ASI Phase A study. [RD-5] Dell’Agnello, S. et al, A Lunar Laser Ranging Retro-Reflector Array for NASA's Manned Landings, the International Lunar Network and the Proposed ASI Lunar Mission MAGIA, Proceedings of the 16th International Workshop on Laser Ranging, Space Research Centre, Polish Academy of Sciences Warsaw, Poland, 2008. [RD-6] International Lunar Network (http://iln.arc.nasa.gov/), Core Instrument and Communications Working Group Final Reports. [RD-7] Yi Mao, Max Tegmark, Alan H. Guth, and Serkan Cabi, Constraining torsion with Gravity Probe B, Physical Review D 76, 104029 (2007). [RD-8] March, R., Bellettini, G., Tauraso, R., Dell’Agnello, S., Constraining spacetime torsion with the Moon and Mercury, Physical Review D 83, 104008 (2011). [RD-9] March, R., Bellettini, G., Tauraso, R., Dell’Agnello, S., Constraining spacetime torsion with LAGEOS, Gen Relativ Gravit (2011) 43:3099–3126. [RD-10] ETRUSCO-2: An ASI-INFN project of technological development and “SCF-Test” of GNSS LASER Retroreflector Arrays, S, Dell’Agnello, 3rd International Colloquium on on Scientific and Fundamental Aspects of the Galileo Programme, Copenhagen, Denmark, August 2011

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