Nex Gen NPOESS Wind Observing Sounder NASAGSFC IDL
Nex. Gen NPOESS Wind Observing Sounder: NASA/GSFC IDL Study and Findings Prepared for Mr. Dan Stockton, Program Executive Officer Program Executive Office for Environmental Satellites Presented by Dr. Wayman Baker NOAA/NASA/Do. D Joint Center for Satellite Data Assimilation and Mr. Bruce Gentry NASA/GSFC/Laboratory for Atmospheres Working Group for Space Based Wind Lidar Wintergreen, VA
Overview Ø Ø Ø Ø Ø Background Why Measure Global Winds from Space? Wind Lidar Societal Benefits NOAA Programs Requiring Atmospheric Winds Space-based Wind Lidar Roadmap GWOS/NWOS Comparisons with ADM Aeolus Instrument Development Laboratory (IDL) Study for a Nex. Gen NPOESS Wind Observing Sounder (NWOS) Concluding Remarks Next Steps/Recommendations 2
Background Ø ESA planning to launch first DWL in 2009: Atmospheric Dynamics Mission (ADM) - Only has a single perspective view of the target sample volume - Only measures line-of-sight (LOS) winds Ø A joint NASA/NOAA/Do. D global wind mission offers the best opportunity for the U. S. to demonstrate a wind lidar in space in the coming decade - Measures profiles of the horizontal vector wind for the first time Ø NASA and NOAA briefings given to: - USAF (March 20, 2007); letter sent from AF Director of Weather on August 1, 2007 to NASA HQ stating: - Of the 15 missions recommended by the NRC, global tropospheric wind measurements was most important for the USAF mission - Willingness to endorse Space Experiments Review Board support via the Do. D Space Test Program - USAF Space Command (May 8, 2007) - Army (May 10, 2007) - NOAA Observing Systems Council (NOSC – June 8, 2007; June 18, 2008) - Navy (June 11, 2007); supporting letter sent on August 8, 2007 - Joint Planning and Development Office and FAA (June 18, 2007) - FAA (May 16, 2008) - NOAA Research Council (May 19, 2008) 3
Background (Cont. ) Ø The National Research Council (NRC) Decadal Survey report recommended a global wind mission The NRC Weather Panel determined that a hybrid Doppler Wind Lidar (DWL) in low Earth orbit could make a transformational impact on global tropospheric wind analyses. Ø “Wind profiles at all levels” is listed as the #1 priority in the strategic plan for United States Integrated Earth Observing System (USIEOS). Ø Cost benefit studies have identified economic benefits >$800 M/year with the measurement of global wind profiles from space 1, 2 1 Cordes, J. (1995), “ Economic Benefits and Costs of Developing and Deploying a Space-Based Wind Lidar, Dept of Economics, George Washington University, D-9502. 2 Miller, K. (2007), “Societal Benefits of Winds Mission, ” Lidar Working Group, http: //space. hsv. usra. edu/LWG/Index. html 4
Why Measure Global Winds from Space ? ØThe Numerical Weather Prediction (NWP) community unanimously identifies global wind profiles as the most important missing observations. Ø Independent modeling studies at NCEP, ESRL, AOML, NASA and ECMWF have consistently shown tropospheric wind profiles to be the single most beneficial measurement now absent from the Global Observing System. 5
Why Wind Lidar? Societal Benefits at a Glance… Civilian Improved Operational Weather Forecasts Hurricane Track Forecast Flight Planning Air Quality Forecast Homeland Security Energy Demands & Risk Assessment Agriculture Transportation Recreation Military Ground, Air & Sea Operations Satellite Launches Weapons Delivery Dispersion Forecasts for Nuclear, Biological, & Chemical Release Aerial Refueling • Estimated potential benefits greater than $800 M per year* • Including military aviation fuel savings greater than $100 M/year** * K. Miller, “Societal Benefits of Winds Mission, ” Lidar Working Group Meeting, February 8, 2007, Miami FL, http: //space. hsv. usra. edu/LWG/Index. html ** AF aviation fuel usage estimate provided by Col. M. Babcock 6
NOAA Programs Requiring Atmospheric Winds* GOAL Program Priority 1 Priority 2 Totals Climate (CL) Climate Observations & Modeling (COM) 1 1 Commerce & Transportation (C&T) Aviation Weather (AWX) 4 4 Marine Weather (MWX) 1 1 Surface Weather (SWX) 2 2 Weather & Water (W&W) Air Quality (AQL) 1 1 Mission Support (MS) Total: 4 Goals Hydrology (HYD) 1 1 Local Forecasts & Warnings (LFW) 3 1 4 Modeling and Observing Infrastructure (MOBI)/Environmental Modeling (EMP) 1 1 8 PROGRAMS 13 2 15 * Data provided by TPIO / CORL Team 7
Nex. Gen Hybrid Doppler Wind Lidar - NWOS NPOESS Wind Observing System For Vertical Wind Profiles 2007 NAS Decadal Survey Nex. Gen NWOS Recommendations for Tropospheric Winds (2026) • 3 D Tropospheric Winds mission called “transformational” and ranked #1 by Weather panel. 3 D Winds also prioritized by Water Cycle panel. “The Panel strongly recommends an aggressive program early on to address the high-risk components of the instrument package, and then design, build, aircraft-test, and ultimately conduct space-based flights of a prototype Hybrid Doppler Wind Lidar (HDWL). ” GWOS (2016) “The Panel recommends a phased development of the HDWL mission with the following approach: – Stage 1: Design, develop and demonstrate a prototype HDWL system capable of global wind measurements to meet demonstration requirements that are somewhat GWOS reduced from operational threshold requirements. All of the critical laser, receiver, detector, and control technologies will be tested in the demonstration HDWL mission. Space demonstration of a prototype HDWL in LEO to take place as early as 2016. – Stage II: Launch of a HDWL system that would meet fully -operational threshold tropospheric wind measurement requirements. It is expected that a fully operational NWOS HDWL system could be launched as early as 2022. ” ADM Aeolus (2010) TODWL (2002 - 2008 ) Operational 3 -D global wind measurements Demo 3 -D global wind measurements Single LOS global wind measurements DWL Airborne Campaigns, ADM Simulations, etc. TODWL: Twin Otter Doppler Wind Lidar [CIRPAS NPS/NPOESS IPO] ESA ADM: European Space Agency-Advanced Dynamics Mission (Aeolus) [ESA] GWOS: Global Winds Observing System [NASA/NOAA/Do. D] Nex. Gen: NPOESS [2 nd] Generation System [PEO/NPOESS]
GWOS/NWOS Comparisons with ADM Attribute ADM GWOS NWOS Orbit Altitude 400 824 Orbit Inclination 98 98 98 Day/Night only Day/Night Components per profile Single –Model estimated second component Two components full horizontal vector Horizontal Resolution 200 km between single LOS’s 300 km with full profile both sides of ground track Vertical Resolution PBL 0. 25 – 0. 5 km Troposphere 1 km PBL 0. 25 - 0. 5 km Tropo 2 – 3 km PBL 0. 25 - 0. 5 Tropo 2 – 3 km Collector Diam. 1. 5 m (1 x) 0. 5 m (4 x) 0. 7 m (4 x) 9
Instrument Design Laboratory [IDL] Study for a Nex. Gen NPOESS Wind Observing Sounder (NWOS): An Operational follow-on to the Global Wind Observing Sounder (GWOS) Advanced Mission Concept Sponsored by Mr. Dan Stockton, Program Executive Officer Program Executive Office for Environmental Satellites
Integrated Design Laboratory—Capabilities and Services Capabilities: – Instrument families ranging from telescopes, cameras, geo–chemistry, lidars, spectrometers, coronographs, etc. – Instrument spectrum support from microwave through gamma ray – LEO, GEO, libration, retrograde, drift away, lunar, deep space, balloon, sounding rockets and UAV instrument design environments – Non-distributed and/or distributed instrument systems Services: – End-to-end instrument architecture concept development – Existing instrument/concept architecture evaluations – Trade studies and evaluation – Technology, risk, and independent technical assessments – Requirement refinement and verification – Mass/power budget allocation – Cost estimation NASA Goddard Space Flight Center—Integrated Design Center 11
GWOS IDL Instrument GPS Star Tracker Hybrid DWL Technology Solution ØThe coherent subsystem provides very accurate (<1. 5 m/s) observations when sufficient aerosols (and clouds) exist. ØThe direct detection (molecular) subsystem provides observations meeting the threshold requirements above 2 km, clouds permitting. ØWhen both sample the same volume, the most accurate observation is chosen for assimilation. Nadir Telescope Modules (4) GWOS Payload Data • • • Dimensions 1. 5 m x 2 m x 1. 8 m Mass 567 Kg Power 1, 500 W Data Rate 4 Mbps Orbit: 400 km, circ, sun-sync, 6 am – 6 pm Selectively Redundant Design +/- 16 arcsec pointing knowledge (post-processed) X-band data downlink (150 Mbps); S-band TT&C Total Daily Data Volume 517 Gbits ØThe combination of direct and coherent detection yields higher data utility than either system alone. GWOS in Delta 2320 -10 Fairing Dimensions (mm) 12
Hybrid DWL Technology Maturity Roadmap Past Funding Laser Risk Reduction Program IIP-2004 Projects 2 -Micron Coherent Doppler Lidar 2 micron laser 1988 Diode Pump Technology 1993 High Energy Technology 1997 Inj. Seeding Technology 1996 TRL 6 to TRL 7 TRL 5 2008 - 2012 Space Qualified Diode Pump Technology Lifetime Validation Pre-Launch Validation -57 Inj. Seeding Technology 2026 2014 - 2016 GWOS Space Qualif. Lifetime Validation Conductive Cooling Techn. Packaged Lidar Ground Demo. 2007 TRL 7 to TRL 9 Autonomous Aircraft Oper WB Autonomous Oper. Technol. 2008 (Direct) 1 micron laser Compact Packaging 2005 2011 - 2013 Autonomous Oper. Technol. Coh. Aircraft Operation DC-8 Conductive Cooling Techn. 1999 ROSES-2007 Projects Operational Nex. Gen NPOESS Pre-Launch Validation High Energy Laser Technology 0. 355 -Micron Direct Doppler Lidar Compact Laser Packaging 2007 Compact Molecular Doppler Receiver 2007 13
NWOS IDL Study User Team
NWOS IDL Study Summary Study Objectives Key Study Assumptions Ø Study the feasibility of modifying the original IDL design for GWOS at 400 km altitude to work at an 824 km altitude on an NPOESS platform Ø 824 km, sun-synchronous, dawndusk, 1730 ascending node local time, 98. 7 deg. Inclination orbit. Ø 5 yr life, 85% reliability goal Ø Consider 3 instrument configurations in a trade space that trades telescope aperture, laser duty cycle, pulse power/repetition rate Ø 2/1 backup lasers direct/coherent Ø 1/0 backup laser electronics direct/coherent Ø Examine impact of new technologies, estimate improvements in laser performance, identify technology tall poles. Ø 1 backup receiver for each (direct & coherent) Ø Both coherent and direct lidars either 100% duty cycle (Configurations 1 & 3) or 50% duty cycle (Configuration 2) Ø Used 10 -year beyond 2008 projections for laser efficiencies: x 2 (direct), x 2. 25 (coherent) Ø Either 4 fixed telescopes (Configurations 1 & 2) or 1 holographic element (Configuration 3) Ø Minimize power, volume, and mass, as much as possible (in that order) Ø Consider redundancy for a multi-year lifetime Key Findings Ø The NWOS IDL designs which follow have shown that the Hybrid Doppler Wind Lidar can be operated at a reasonable electrical power and with reasonable reliability for the 5 year mission on board the NPOESS second generation satellite, Nex. Gen. Ø There are no tall poles in any of the technical developments needed in the future to develop an NWOS. Ø Because the proof-of-concept GWOS flight is in advance of the NWOS, there should be good opportunity to verify the assumed requirements. 15
Preliminary Instrument Design Results Nex. Gen Hybrid Doppler Wind Lidar - NWOS NPOESS Wind Observing System For Vertical Wind Profiles I n t e g r a t e d D e s i g n C a p a b i l i t y / I n s t r u m e n t D e s i g n L a b o r a t o r y Design Study Objectives NWOS Wind Measurement Concept • Study the feasibility of modifying the original ISAL design for GWOS at 400 km to work at an 824 km altitude on an NPOESS platform • Consider 3 instrument configurations in a trade space that tweaks telescope aperture, direct laser duty cycle, and direct laser pulse power/rep rate – – Create multiple mechanical, thermal, and optical models Each discipline engineer consider the impacts of all 3 configurations to their subsystems • Minimize power, volume, and mass, as much as possible (in that order) • Consider redundancy for a 5 year lifetime Requirements • Spacecraft accommodations for NWOS: (IDL Study Starting Assumptions) – – – Mass - 650 kg Power - 1000 W Dimensions in cm (X, Y, Z) - (170, 170) Data Rates - 10 Mbps On-orbit life - 5 years NWOS Location – Nadir deck • Orbital Altitude: 824 km • Ascending Node: 1730 local (Sun-synchronous dawn-dusk orbit) NPOESS Nex. Gen Lidar Backscatter From Aerosols & Molecules DOPPLER RECEIVER: Multiple Choices drive science/technology trades • Coherent ‘heterodyne’ (e. g. SPARCLE-NASA/La. RC) • Direct detection “Double Edge” (e. g. Zephyr-NASA/GSFC) • Direct detection “Fringe Imaging” (e. g. Michigan Aerospace) Backscattered Spectrum DOP Aerosol (l-2) • Orbital inclination: ~98. 7 o • Orbital period: ~101 minutes, 14 orbits/day Molecular (l-4) These requirements held for all configurations under consideration. Frequency
Preliminary Instrument Design Results Nex. Gen Hybrid Doppler Wind Lidar - NWOS NPOESS Wind Observing System For Vertical Wind Profiles I n t e g r a t e d D e s i g n C a p a b i l i t y / I n s t r u m e n t D e s i g n L a b o r a t o r y Launch Concept for the Atlas 5 - 4 m Diameter Fairing NPOESS 1730 LAN Spacecraft NPOESS LAN 1730 S/C Sensor Configuration 4. 5 m 5. 7 m = Space Considered for NWOS 3. 75 m dia. NWOS HDWL Instrument Configurations NWOS HDWL Instrument Trade Summary Configuration #1 Configuration #2 Configuration #3 Optical Design Shared, Inverted GWOS, 4 azimuths 100 % Duty Cycle Shared, Inverted GWOS, 4 azimuths 50 % Duty Cycle Common Aperture, Sh. ADOE, 4 azimuths 100 % Duty Cycle Mass [kg] 595 661 Telescope Module Dimensions (ht x dia) 100 x 160 cm 127 x 160 Structural Assem. Dimensions Configuration 1 and 2 (Inverted GWOS) Configuration 3 (Sh. ADOE) 72. 5 x 170 cm Telescope Primary Diameter 0. 7 m (0. 5 m Coherent) 1. 24 m (0. 72 m Coherent) Orbital Avg Power [W] 1382 898 1382 Peak Power [W] Standby Power [W] Warmup Power [W] 1382 719 861 No contingency added (+30%) 1382
Preliminary Instrument Design Results Nex. Gen Hybrid Doppler Wind Lidar - NWOS NPOESS Wind Observing System For Vertical Wind Profiles I n t e g r a t e d D e s i g n C a p a b i l i t y / I n s t r u m e n t D e s i g n L a b o r a t o r y Launch Concept for the Atlas 5 - 4 m Diameter Fairing NWOS HDWL Instrument Configurations NPOESS 1730 LAN Spacecraft 4. 5 m 5. 7 m Configuration 1 and 2 (Inverted GWOS) 3. 75 m dia. NWOS HDWL Instrument Trade Summary Configuration #1 Configuration #2 Configuration #3 Optical Design Shared, Inverted GWOS, 4 azimuths 100 % Duty Cycle Shared, Inverted GWOS, 4 azimuths 50 % Duty Cycle Common Aperture, Sh. ADOE, 4 azimuths 100 % Duty Cycle Mass [kg] 595 661 Telescope Module Dimensions (ht x dia) 100 x 160 cm 127 x 160 Structural Assem. Dimensions 72. 5 x 170 cm Telescope Primary Diameter 0. 7 m (0. 5 m Coherent) 1. 24 m (0. 72 m Coherent) Orbital Avg Power [W] 1382 898 1382 Peak Power [W] Standby Power [W] Warmup Power [W] 1382 719 861 No contingency added (+30%) 1382 Configuration 3 (Sh. ADOE) NWOS HDWL Instrument Parameters Configuration #1 Configuration #2 Configuration #3 Direct Laser - Number of Sources - Rep. Rate - Pulse energy - FOV - Detector 355 nm 3 100 Hz 0. 9 – 1 J @1064 nm <100 urad EMCCD array 355 nm 2 100 Hz 0. 9 – 1 J @1064 nm <100 urad EMCCD array 355 nm 3 100 Hz 0. 9 – 1 J @1064 nm <100 urad EMCCD array Coherent Laser - Number of Sources - Rep Rate - Pulse energy - FOV - Detector 2 microns 2 5 Hz 1. 2 J Diffraction Limited In. Ga. As photodiode On-board Computational Requirements RAD 6000 Processor @ 3. 9 Mbs Vibrational Modes Gen. Fidelity of structural model not high enough to predict Unique S/Interface IEEE 1394 A
NWOS IDL Study Conclusions Ø The NWOS IDL design study has shown that the Hybrid Doppler Wind Lidar can be operated at a reasonable electrical power and with reasonable reliability for the 5 year mission on board the NPOESS second generation satellite. Ø There are no tall poles that depend on unforeseen technical developments in the future. Ø Because the proof-of-concept GWOS flight is in advance of the NWOS, there should be good opportunity to verify the assumed requirements. Return 19
Next Steps/Recommendations NPOESS evaluation of ADM data Ø Participate on ESA’s ADM Aeolus Team [Launch 2009] to help establish good data/products and to enable Aeolus data gathering/usage for NWOS studies Ø Perform study investigating the utility / impact of NWOS data for Nex. Gen using Aeolus data as proxy data and the NWOS projected capabilities from the previous ADM potential impact studies NWOS concept development Ø Estimate NWOS Instrument Cost - use NWOS detailed Parts List developed from IDL NWOS Study Ø Perform mission conceptual design study - NWOS Study User Team & GSFC MDL (Mission Design Laboratory) 20 20
Supporting Material 21
Observations Needed as a Function of Forecast Length Return 22
Which Upper Air Observations Do We Need ? ØNumerical weather prediction requires independent observations of the mass (temperature) and wind fields ØThe global three-dimensional mass field is well observed from space ØNo existing space-based observing system provides vertically resolved wind information => horizontal coverage of wind profiles is sparse 23
Current Mass & Wind Data Coverage Upper Air Mass Observations Upper Air Wind Observations 24
Forecast Impact Using Actual Aircraft Lidar Winds in ECMWF Global Model (Weissmann and Cardinali, 2007) Ø DWL measurements reduced the 72 -hour forecast error by ~3. 5% Ø This amount is ~10% of that realized at the oper. NWP centers worldwide in the past 10 years from all the improvements in modelling, observing systems, and computing power Ø Total information content of the lidar winds was 3 times higher than for dropsondes Green denotes positive impact Mean (29 cases) 96 h 500 h. Pa height forecast error difference (Lidar Exper minus Control Exper) for 15 - 28 November 2003 with actual airborne DWL data. The green shading means a reduction in the error with the Lidar data compared to the Control. 25 The forecast impact test was performed with the ECMWF global model.
Airborne Doppler Wind Lidars In T-PARC/TCS-08 Experiment in Western North Pacific Ocean (2008) to investigate tropical cyclone formation, intensification, structure change and satellite validation ØONR-funded P 3 DWL (1. 6 um coherent) ØPI is Emmitt (SWA) ØWill co-fly with NCAR’s ELDORA and dropsondes ØWind profiles with 50 m vertical and 1 km horizontal resolution Ø Multi-national funded 2 um DWL on DLR Falcon Ø PI is Weissmann (DLR) Ø Will fly with dropsondes u, v, w, TAS, T, P, q Dropsondes u, v , P, T, q u, v Lidar horizontal W wind speed ' Data will be used to investigate impact of improved wind data on numerical forecasts T-PARC: THORPEX Pacific Asian Regional Campaign TCS-08: Tropical Cyclone Study 2008 26
Simulated Impact of Space-based Wind Lidar Observations on a Hurricane Track Forecast (R. Atlas et al. ) Hurricanes Tracks Green: Actual track Red: Forecast beginning 63 h before landfall with current data Blue: Improved forecast for same time period with simulated DWL data Note: A significant positive impact was obtained for both land falling hurricanes in the 1999 data; the average impact for 43 oceanic tropical cyclone verifications was also significantly positive 27
Lidar Winds Will Improve Hurricane Forecasts • • Reduce preventable property damage ~ $212 M/year 2, 3 Reduce over-warnings ~ $74 M/year 2, 3 • 17% less landfall warning error for average of 2 storms/year 1 • Typically warn ~ 350 miles of coast, over-warn 220 miles • Estimate 17% reduction in over-warning with lidar winds, 37 miles • @ $1 M / mile precautionary costs saves $37 M/storm, $74 M/year 4 1 Storm climatology and simulations for global 3 D winds in NWP 2 Cordes, J. J. , “Economic Benefits and Costs of Developing and Deploying A Space-Based Wind Lidar, ” GWU, NOAA Contract 43 AANW 400233, March 1995 3 K. Miller, “Societal Benefits of Lidar Winds”, Lidar Working Group, ” February 8, 2007 4 www. ncdc. noaa. gov/billionz. html 28
Summary of Benefits Estimates ($M/year)*a * K. Miller, “Societal Benefits of Winds Mission, ” Lidar Working Group Meeting, February 8, 2007, Miami FL, http: //space. hsv. usra. edu/LWG/Index. html 29
NWOS Study Objective I n t e g r a t e d D e s i g n C e n t e r / I n s t r u m e n t D e s i g n L a b o r a t o r y • Study the feasibility of modifying the original ISAL design for GWOS at 400 km to work at an 824 km altitude on an NPOESS platform • Consider 3 instrument configurations in a trade space that tweaks telescope aperture, direct laser duty cycle, and direct laser pulse power/rep rate – Create multiple mechanical, thermal, and optical models – Each discipline engineer consider the impacts of all 3 configurations to their subsystems • Minimize power, volume, and mass, as much as possible (in that order) • Consider redundancy for a 5 year lifetime Return 30
Doppler Lidar Measurement Concept I n t e g r a t e d D e s i g n C e n t e r / I n s t r u m e n t D e s i g n L a b o r a t o r y DOPPLER RECEIVER - Multiple flavors - Choice drives science/technology trades • Coherent ‘heterodyne’ (e. g. SPARCLE/La. RC) • Direct detection “Double Edge” (e. g. Zephyr/GSFC) • Direct detection “Fringe Imaging” (e. g. Michigan Aerospace) Backscattered Spectrum DOP Aerosol (l-2) Molecular (l-4) Frequency Return
NWOS Hybrid Doppler Wind Lidar Measurement Geometry: 824 km Return light: t+6. 6 ms, 62 m, 8. 7 microrad 7. 4 km/s Second shot: t+200 ms, 5 ms 1489 m, 207 microrad 37 m, 5. 3 microrad First Aft Shot t + 190 s 90° fore/aft angle in horiz. plane ° 45 FORE 824 km AFT 1253 km 45 deg azimuth Doppler shift from S/C velocity ± 3. 6 GHz ± 21 GHz 8 m (86%) 180 ns (27 m) FWHM (76%) ° Max nadir angle to strike earth 62. 3 deg 45 2 lines LOS wind profiles 1 line “horiz” wind profiles ° 53 889 km 60/2400 shots = 12 s = 78 km 626 km Goddard Space Flight Center 626 km 1/5 s = 1319 m 1/200 s = 33 m Return 32
NWOS Requirements–Spacecraft and Orbit I n t e g r a t e d D e s i g n C e n t e r / I n s t r u m e n t D e s i g n L a b o r a t o r y • Spacecraft accommodations for NWOS: (starting assumptions) Mass - 650 kg Power - 1000 W Dimensions in cm (X, Y, Z) - (170, 170) cm Data Rates - 10 Mbps On-orbit life - 5 years NWOS Location – Nadir deck Reliability Goal – 85% These requirements hold for all configurations under consideration. From GWOS Systems • Orbital Altitude: 824 km • Ascending Node: 1730 local (Sun-synchronous dawn-dusk orbit) • Orbital inclination: ~98. 7 o • Orbital period: ~101 minutes, 14 orbits/day Courtesy D. Evans – – – – Return 33
NWOS System Configurations (Courtesy M. Clark and D. Palace) I n t e g r a t e d D e s i g n C e n t e r / I n s t r u m e n t D e s i g n L a b o r a t o r y Configuration 1 and 2 (Inverted GWOS) Configuration 3 (Sh. ADOE) Return 34
NPOESS LAN 1730 S/C Sensor Configuration I n t e g r a t e d D e s i g n C e n t e r / I n s t r u m e n t D e s i g n L a b o r a t o r y = Space Considered for NWOS Return 35
Launch Concept for the Atlas 5 - 4 m Diameter Fairing NPOESS 1730 LAN Spacecraft I n t e g r a t e d D e s i g n C e n t e r / I n s t r u m e n t D e s i g n L a b o r a t o r y 4. 5 m 5. 7 m 3. 75 m dia. Return 36
NWOS System Description (1 of 2) I n t e g r a t e d D e s i g n C e n t e r / I n s t r u m e n t D e s i g n L a b o r a t o r y Configuration #1 Configuration #2 Configuration #3 Optical Design Shared, Inverted GWOS, 4 azimuths 100 % Duty Cycle Common aperture, Sh. ADOE, 4 azimuths 100 % Duty Cycle Mass [kg] 595 661 Telescope Module Dimensions (height x diameter) 100 x 160 cm 127 x 160 Structural Assembly Dimensions 72. 5 x 170 cm Telescope Primary Diameter 0. 7 m (0. 5 m Coherent) 1. 24 m (0. 72 m Coherent) Orbital Average Power [W] 1382 898 1382 Peak Power [W] Standby Power [W] Warmup Power [W] 1382 719 1382 861 * No contingency added (+30%) Return 37
NWOS System Description (2 of 2) I n t e g r a t e d D e s i g n C e n t e r / I n s t r u m e n t D e s i g n L a b o r a t o r y Configuration #1 Configuration #2 Configuration #3 Direct Laser - Number of Sources - Rep. Rate - Pulse energy - FOV - Detector 355 nm 3 100 Hz 0. 9 – 1 J @1064 nm <100 urad EMCCD array Coherent Laser - Number of Sources - Rep Rate - Pulse energy - FOV - Detector 2 microns 2 5 Hz 1. 2 J Diffraction Limited In. Ga. As photodiode On-board Computational Requirements RAD 6000 Processor @ 3. 9 Mbs Vibrational Modes Generated Fidelity of structural model not high enough to predict Unique Spacecraft Interface IEEE 1394 A Return 38
- Slides: 38