Satellite and Lunar Laser Ranging: Science and Technology - PowerPoint PPT Presentation

Satellite and Lunar Laser Ranging: Science and Technology Applications Simone'Dell’Agnello'(INFN1LNF,'Frasca8'Na8onal'Labs)' for'the'SCF_Lab'Group:'Dell’Agnello'S.,'Delle'Monache'G.,'ViGori'R.,'Boni'A.,'Cantone' C.,'Ciocci'E.,'Mar8ni'M.,'Patrizi'G.,'Tibuzzi'M.,'IntaglieGa'N.,'Salvatori'L.,'Lops'C.,' Contessa'S.,'Porcelli'L.,'Mondaini'C.,'Tuscano'P.,'Maiello'M. ' ''''''''''''''''''''''' (www.lnf.infn.it/esperimen8/etrusco)' Winter'College'on'Op8cs:' Light:'a'bridge'between'Earth'and'Space' IYL12015' ICTP,'Trieste,'Italy'1'February'19,'2015'

Outline • Laser'Retroreflectors'and'Laser'Ranging'in'Space' • Satellite'Laser'Ranging'Science'applica8on:'Interna8onal' Terrestrial'Reference'System' • SCF_Lab'@INFN,'Italy:'Unique'Test'Facility'for'Laser' Retroreflectors'in'Space' • Technology'Applica8on:'Global'Naviga8on'Satellite'System'' • Lunar'Laser'Ranging'Science'Applica8on:'Test'of'General' Rela8vity' • Applica8ons'to'Explora8on'of'Mars'System' • Conclusions'and'vision'foreword' 19/Feb/2015,'ICTP1Trieste' S.'Dell'Agnello'(INFN1LNF)'et'al' 2'

Laser retroreflector working principle ! Cube Corner Retroreflectors (CCRs) made of special fused silica glass ! (Suprasil). Total internal reflection (TIR) on each of the faces causes ! Retroreflection in the same direction of incidence ! LAS ER ! LASER ! IN ! OUT ! Triple'(retro)reflec8on'around'the'corner'of'the'cube' 19/Feb/2015,'ICTP1Trieste' S.'Dell'Agnello'(INFN1LNF)'et'al' 3'

Laser Retroreflectors ! For ground positioning metrology: CCRs typically mounted inside half-spheres ! Taylor1Hobson' sphere' For'angular' measurements' 19/Feb/2015,'ICTP1Trieste' S.'Dell'Agnello'(INFN1LNF)'et'al' 4'

Laser1retroreflector'ground'applica8ons: ' ' theodolite'(or'laser' � tracker � ),'retroreflector,'8me1of1flight Used'for'posi8oning'metrology'of'large'physics'installa8ons,'like' Par8cle'accelerators'and'par8cle'physics'experiments'(at'CERN'in' In'Geneva,'Fermilab'in'USA,'Desy'in'Germany,'DA Φ NE'in'Italy'…)'' 19/Feb/2015,'ICTP1Trieste' S.'Dell'Agnello'(INFN1LNF)'et'al' 5'

Laser'Ranging'in'space :'measurement'of'8me1of1flight'from'ground'laser' sta8on'to'satellite'equipped'with'laser'retroreflectors:'pulsed'laser,'precision' ' 8ming'electronics,'atomic'clock'and'op8cal'telescope'and'detector t t t Δ = − stop start stop c t Δ d ≈ 2 start LASER

Matera'Laser'Ranging'Observatory' Led'by'G.'Bianco,'PI'of'“Laser'Ranging'to'Galileo”'for'ASI' Telescope'diameter'='1.5'm' SLR.'LLR'since'2010' 19/Feb/2015,'ICTP1Trieste' S.'Dell'Agnello'(INFN1LNF)'et'al' 7'

Satellite/Lunar'Laser'Ranging'(SLR/LRR) ' Physical'point=to='point'link'of'laser'pulses'between'ground'and'space ' Unambiguous'posi8on/distance'measurement'(‘laser'range’)'to'cube' corner'retroreflectors'(CCRs)'with'short'laser'pulses'and'a'8me1of1flight' technique.'Time1tagging'with'H1maser'clocks' Moon' Earth' • 'Precise 'posi8oning'(normal'points'at'mm'level,' orbits'at'cm'level)' • 'Absolute 'accuracy'(used'to'define'Earth'center' of'mass,'geocenter,'and'scale'of'length)'' • ' Passive ,'maintenance1free'Laser'Retroreflector' Arrays'( LRAs) ' S.'Dell'Agnello'(INFN1LNF)'et'al' 19/Feb/2015,'ICTP1Trieste' 8'

Lunar'Laser'Ranging'(LLR)' Satellite'Laser'Ranging'(SLR)' Time'of'Flight'measurement'(ToF)' Cube corner retro-reflectors, ! CCRs Rs ! LAGEOS: S: ! ToF, h ~ h ~ 6 6000 Km Km ! atmospheric ! corrections Retroreflection ! LLR ' Normal ! reflection ! 19/Feb/2015,'ICTP1Trieste' S.'Dell'Agnello'(INFN1LNF)'et'al' 9'

Laser Geodynamics Satellites (LAGEOS) ! LAGEOS I (1976; NASA), LAGEOS II (1992; NASA/ASI) ! LAGEOS � Sector � , engineering prototype by NASA-GSFC, now at INFN-LNF Frascati for testing ! 19/Feb/2015,'ICTP1Trieste' S.'Dell'Agnello'(INFN1LNF)'et'al' 10'

Laser Geodynamics Satellites (LAGEOS) ! LAGEOS I (1976; NASA), LAGEOS II (1992; NASA/ASI) ! Summers students ! LAGEOS � Sector � , engineering prototype by NASA-GSFC, now at INFN-LNF Frascati for testing !

LAGEOS.laser2tracked.by.ILRS.sta:ons.of.Matera.(IT),. Herstmonceux.(UK),.Graz.(AT),.OCR.(FR) 19/Feb/2015,'ICTP1Trieste' S.'Dell'Agnello'(INFN1LNF)'et'al' 12'

SLR/LLR examples ! LAGEOS' ! (al8tude'~6000'km):' S ToF'~'0.05'sec' ! L Apollo'LRA' ! R ! Moon' (d'~'380000'km):' ToF'~'2.5'sec' S.'Dell'Agnello'(INFN1LNF)'et'al' 19/Feb/2015,'ICTP1Trieste' 13'

Centro.di.Geodesia.Spaziale. Giuseppe'Colombo' Matera,.Italy. Site.posi:on.known.by.SLR,.VLBI,.GNSS.(“tri2located”) MLRO,' Matera'Laser'Ranging'Observatory' LLR'since'2010' Giuseppe Colombo, 1920-1984 19/Feb/2015,'ICTP1Trieste' S.'Dell'Agnello'(INFN1LNF)'et'al' 14'

Satellite/Lunar'Laser'Ranging'(SLR/LLR)' ' Time'of'Flight'(ToF)'measurements'of'short'laser'pulses' ' 1 st 'SLR'to'cube'corner'retroreflectors'(CCRs):' October'31,'1964'from'NASA1GSFC,'by'H.'Plotkin'et'al' 19/Feb/2015,'ICTP1Trieste' 15' S.'Dell'Agnello'(INFN1LNF)'et'al'

Intern. Terrestrial Reference System (ITRS) ! SLR CONSTELLATION ! • Geocenter from SLR/LAGEOS ! Low orbits to the Moon ! • Scale from SLR and VLBI ! • Orientation from VLBI ! • Distribution w/ GNSS. Also DORIS ! For Geodesy, GNSS, Gravity, ! Earth Observation ! LAGEOS ! S.'Dell'Agnello'(INFN1LNF)'et'al' 19/Feb/2015,'ICTP1Trieste' 16'

SCF_Lab:.retroreflector.characteriza:on. • Two'Op8cal'Ground'Support'Equipment'(OGSE)' • SCF'(top'right)'SCF1G'(boGom'right)'dedicated'''to' Galileo,'other'GNSS' • Two'AM0'sun'simulators,'IR'thermometry' • Detailed'op8cal'tes8ng' • J.'Adv.'Space'Res.'47'(2011)'822–842' AM0'sun'simulator' 19/Feb/2015,'ICTP1Trieste' 17' S.'Dell'Agnello'(INFN1LNF)'et'al'

SCF_Lab:.retroreflector.characteriza:on. • Two'Op8cal'Ground'Support'Equipment'(OGSE)' • (BeGer'than)'Class'10000'(ISO'7)'Clean'Room'' 19/Feb/2015,'ICTP1Trieste' 18' S.'Dell'Agnello'(INFN1LNF)'et'al'

SCF-Test: Retroreflector characterization • Accurately laboratory-simulated space conditions • TV + Sun (AM0) simulators • IR and contact thermometry • Payload roto-translations and thermal control • Deliverables / Retroreflector Key Performance Indicators • Thermal relaxation time of retroreflector ( τ CCR ) • Optical response • Far Field Diffraction Pattern ( FFDP ) • Wavefront Fizeau Interferometer (WFI), vibe-insensitive • Invariant lidar Optical Cross Section, OCS, in air/ isothermal conditions S.'Dell'Agnello'(INFN1LNF)'et'al' 19/Feb/2015,'ICTP1Trieste' 19'

CCRs in space: thermal & optical issues ! • CompensaEon'of'staEon=satellite'Velocity'AberraEon'(or'“point=ahead”'effect) :' requires'accurate'dihedral'angle'offsets'w/0.5'arcsec'accuracy'to'control'shape''''' (angle' θ )'and'intensity'of'laser'return'(FFDP,'Far'Field'Diffrac8on'PaGern)'to'ground' FFDP peak # 1 ! Laser from Earth ! Cube Corner Retro-reflector in space (CCR) ! FFDP peak # 2 ! FFDP peaks ! Station emits laser from A ! back to ground ! then moves to B ! • Thermal perturbations: temperature gradients across CCR can degrade laser GNSS velocity aberration is ! performance ! θ ~ 2 v/c cos φ ~ 25 µ rad (~ 500 m on the ground) ! • A CCR could work at STP, BUT not in Achievable with choice of CCR diameter or space for thermal reasons ! variety of dihedral angle offsets from 90 o ! • Design CCR array to control thermal Nominal distance between FFDP peaks is ! and optical properties ! 2 x θ = 50 µ rad=> 1 Km ! • SCF-Test : characterize performance at dedicated INFN-LNF facility ! ! 19/Feb/2015, ICTP-Trieste ! S. Dell'Agnello (INFN-LNF) et al 20 !

GLONASS, GPS and GIOVE-A/B CCRs ! GIOVE1A'@'Estec' Microwave antennas ! LRA ! Benefits'of'LRAs'on'GNSS' ' • ''Only'independent'valida8on/calibra8on' of'GNSS'orbits,'with'214x'beGer'precision' • ''Absolute'posi8oning,'ie,'wrt'ITRS' • ''Long'term'stability'&'geode8c'memory' • ''Therefore:' combining'SLR+GNSS'data' will'improve'orbit'reconstrucEon ' 21' S.'Dell'Agnello'(INFN1LNF)'et'al' 19/Feb/2015,'ICTP1Trieste'

Russian GLONASS/GPS/GIOVE-A/B reflectors ! Al1coated'fused'silica'laser'retroreflector'technology,'with' thermal'moun8ng'not'op8mized'as'LAGEOS'and'Apollo' Technology'used'since'the'1980s'un8l'2010s.' Coa8ng'now'abandoned'due'to'SLR'return'inefficiencies' experienced'by'ILRS'and'due'to'SCF1Test'results'' Third and last GPS flight array ever made by USSR for GPS ! ~19 x 24 cm 2 ! ~1.3 Kg, ! 32 CCRs. ! Property of University of Maryland (C. Alley, D. Currie), SCF-Tested at INFN-LNF ! S.'Dell'Agnello'(INFN1LNF)'et'al' 22' 19/Feb/2015,'ICTP1Trieste'

SCF-Test of GLO/GIOVE: de-qualification of Al coating ! Sun on : laser return (FFDP) ! velocity'aberraEon ' severely degraded (2 km distance) ! Factor'~7'reducEon' FFDP on CCD ! of'FFDP'at'GNSS' Sun Simulator ON % AM0 Sun ! simulator Sun off : laser return ! Sun Simulator OFF % (FFDP) peaks restored at 1km distance ! FFDP on CCD ! ILRS ! Earth shadow ! Satellite ! with CCR ! IR T OUTER CCR FACE (K) vs t (sec) ! 19/Feb/2015,'ICTP1Trieste' S.'Dell'Agnello'(INFN1LNF)'et'al' 23'

Making SCF movies (of laser return) ! SCF=Test'of'' GLONASS,'' GIOVE ' T OUTER CCR FACE (K) ! vs. time (sec) ! 19/Feb/2015,'ICTP1Trieste' S.'Dell'Agnello'(INFN1LNF)'et'al' 24'