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LDCM SRR/MDR/PNAR 22-24 April 2008. Landsat Data Continuity Mission and Beyond. Mike Wulder On behalf of Landsat Science Team. 4th Global Vegetation Workshop June 18, 2009. Landsat’s role in understanding a changing Earth.
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LDCM SRR/MDR/PNAR 22-24 April 2008 Landsat Data Continuity MissionandBeyond Mike Wulder On behalf of Landsat Science Team 4th Global Vegetation Workshop June 18, 2009
Landsat’s role in understanding a changing Earth July 5, 1973 August 13, 1984 June 30, 2000 Landsat includes the acquisition, archival, and distribution of global, synoptic, and repetitive coverage multi-spectral imagery of the Earth's land surfaces at a scale where natural and human-induced changes can be detected, characterized, and monitored over time. 4th Global Vegetation Workshop
Driving the need for Landsat… • Science – understanding a changing planet • “Landsat is a climate instrument” – US CCSP • Operational applications – managing and monitoring resources for economic and environmental quality, public health and welfare, and national security • ALL require: • A global perspective • A long-term record of observation • Huge amounts of well-calibrated data 4th Global Vegetation Workshop
36+ Years of Continuous Landsat Global Land Observation • Landsat 1 was launched July 23, 1972 (MSS) • Landsat 2 was launched January 22, 1975 (MSS) • Landsat 3 was launched March 5, 1978 (MSS) • Landsat 4 was launched July 16, 1982 (TM) • Landsat 5 was launched March 1, 1984 (TM) • Landsat 6 was launched October 5, 1993, but never reached orbit • Landsat 7 was launched April 15, 1999, May 2003 SLC-Off (ETM+) • Landsat 8 is scheduled for launch in December 2012 http://landsat.usgs.gov/ 4th Global Vegetation Workshop
Landsat 5 and 7 are still functioning… • Landsat 5 – 25 years since launch (March 1, 1984) • TM - functioning normally • No on-board data recorders • Landsat 7 – nearly 5 years beyond design life • 1999 Launch • ETM+ - Scan Line Corrector Failure • Robust global acquisitions Both satellites have enough fuel to operate through 2012. 4th Global Vegetation Workshop
And… • On December 8, 2008, the USGS made the entire 36-year long Landsat archive available to anyone via the Internet at no cost. • GeoTIFF format • Orthorectified “GIS-ready” • Calibrated across missions and instruments 4th Global Vegetation Workshop
Free Landsat Data… • Newly acquired Landsat 5 and 7 data with <30 percent cloud cover are automatically processed and placed on-line for immediate downloading. • All other Landsat scenes (over 2.2 million) are available at no charge via an on-demand ordering and downloading capability. • Initial experience - significant demand… • In 2001 - 19,300 Landsat images were distributed to users. • In January 2009, nearly 73,000 scenes were downloaded – an average of almost 2400 scenes per day. 4th Global Vegetation Workshop
Landsat Level 1T (L1T) Specification • Pixel size: 15m/30m/60m • Media type: Download (no cost) • Product type: L1T (precision & terrain corrected) • Output format: GeoTIFF • Map projection: UTM • Datum: WGS84 • Orientation: North up • Resampling: Cubic convolution • Landsat holdings are accessible via: • GloVis (glovis.usgs.gov) • Earth Explorer (earthexplorer.usgs.gov) 4th Global Vegetation Workshop
Changes and improvements are underway… • NASA and the USGS are developing the Landsat Data Continuity Mission (LDCM), which will further extend the global land record. 4th Global Vegetation Workshop
Launch date – December 2012 • 5 year mission design life with 10 years of consumables • Support seasonal, global, image data collection • World Reference System – 2 (WRS-2), mid-morning equatorial crossing, 16 day repeat • Collect, ingest, and archive at least 400 global WRS-2 scenes/day for U.S. archive • Operational Land Imager (OLI) - 9 spectral bands - 30 m for VIS/NIR/SWIR, 15m for PAN • Instrument data will be quantized in 12-bits 4th Global Vegetation Workshop
LDCM Milestones • OSTP directed NASA and USGS to implement the LDCM as a “free-flyer” satellite in Dec., 2005 • NASA and USGS signed Final Implementation Agreement in April, 2007 • Operational Land Imager (OLI) contract was awarded to Ball Aerospace Technology Corporation in July, 2007 • Atlas V launch vehicle was selected in Oct. 2007 • Spacecraft contract was awarded to General Dynamics Advanced Information Systems in April, 2008 • Mission Operations Element (MOE) contract awarded to The Hammers Company in September, 2008 • Key Decision Point - B review on September 25, 2008 • Mission Preliminary Design Review (PDR) is scheduled for July, 2009 leading to a Key Decision Point - C review in Oct., 2009 4th Global Vegetation Workshop
LDCM at KDP-B Programmatic Status • LDCM approved to proceed into Project Life Cycle Phase B • Key Decision Point – B (KDP-B) Review (Initial Confirmation) conducted on September 25, 2008 • As a NASA Category 1 Mission, LDCM requires highest level approval of the Agency Program Management Council chaired by NASA Associate Administrator, Chris Scolese, to initiate each phase of the project life cycle • Phase B is the system preliminary design phase following concept studies, Pre-Phase A, and concept and technology development, Phase A • LDCM spent 9 years in formulation, re-formulation, Pre-Phase A, and Phase A 4th Global Vegetation Workshop
New LDCM Launch Readiness Date • Major finding of System Requirements Review • Original launch readiness date, July, 2011 was considered excessively aggressive and added risk to the mission • “The existing LDCM development schedule is not achievable. There is less than a 20% chance that the July 24, 2011 Launch Readiness Date (LRD) can be achieved.” • Mission schedules must reflect a 70% confidence level (70% chance of making launch date) • Reconciliation of numerous independent schedule assessments and project’s own assessment resulted in a retargeted 70% confidence launch date for LDCM • Through KDP-B Process • Retargeted launch date to December, 2012 • Provides appropriate level of confidence • Approved by NASA Agency Program Management Council 4th Global Vegetation Workshop
Operational Land Imager (OLI) Contract awarded to Ball Aerospace Technical Corp. (BATC) July 2007 Critical Design Review Completed Oct. 2008 • Pushbroom VIS/NIR/SWIR sensor • Four-mirror telescope with front aperture stop • FPA consisting of 14 sensor chip assemblies, passively cooled • Aperture 135 mm • F number 6.4 • 36 um / 18 um detectors (MS / Pan) Courtesy of BATC 4th Global Vegetation Workshop
OLI Spectral Bands 4th Global Vegetation Workshop
Launch Vehicle In September 2007, the Atlas V 401 launch vehicle was selected for LDCM by the Kennedy Space Center. 4th Global Vegetation Workshop
LDCM Spacecraft Contract awarded to General Dynamics Advanced Information Systems (GDAIS) in April 2008 Courtesy of GDAIS 4th Global Vegetation Workshop
STRUCTURE • Aluminum primary structure • Externally mounted components • Clear instrument FOVs • Clear instrument radiative paths • THERMAL CONTROL • Passive with heaters • Constant conductance heat pipes (if needed) • COMMUNICATIONS • S-band to GN/LGN: 1, 32kbps uplink: and 2k,16k, 32k, or 1 Mbps downlink • Omni antennas • TDRSS - SA: 1 kbps return and 2 or 32 Kbps forward • X-band: 384 Mbps science data • PROPULSION • Hydrazine blow-down propulsion module • Eight 22N Redundant Thrusters • GUIDANCE, NAVIGATION • & CONTROL • 2 of 3 star trackers active • High precision IRU • Honeywell reaction wheels • SADA with damper • 3-axis stabilized • Zero momentum biased • ELECTRICAL POWER • Single wing single axis articulated GaAs solar array provides 4300 W at EOL • 125 amp-hour NiH2 battery • Unregulated 22 V - 36 V power bus • Two power distribution boxes • COMMAND & DATA HANDLING • cPCI architecture; RAD750 CPU • 3.1 Tbit (BOL) solid state recorder • 265 Mbps peak OLI data transfer • 26.2 Mbps peak TIRS data transfer • High rate PB at 384 Mbps LDCM Spacecraft Courtesy of GDAIS 4th Global Vegetation Workshop
Thermal Infrared Sensor (TIRS) • NASA President’s FY10 Budget Request (announced May 07, 2009) • “Starting in FY2009, NASA will develop a Thermal Infrared Sensor (TIRS) instrument, to be flown on LDCM or (potentially) some other spacecraft. A decision as to which spacecraft will carry TIRS will be made by summer of 2009. Meanwhile, funding for TIRS (approximately $150-175M) is now carried within the LDCM budget.” 4th Global Vegetation Workshop
TIRS Status • NASA GSFC has initiated development of TIRS for the LDCM spacecraft • NASA HQ directed GSFC to begin a Phase A instrument study in July, 2009 on the basis of Congressional interest in continued thermal imaging • GSFC established TIRS specifications and developed instrument concept • TIRS development has progressed through three successful reviews by independent board • System Concept Review held October 17, 2008 • System Requirements Review held February 02 - 03, 2009 • Preliminary Design Review held May 27 - 28, 2009 • Baseline design meets or exceeds TIRS requirements • Aggressive TIRS development schedule maintains Dec. 2012 LDCM launch readiness data • TIRS delivered for observatory integration by Dec., 2011 4th Global Vegetation Workshop
LDCM Thermal Requirements • 120 m resolution was felt to be sufficient to resolve most center-pivot irrigation fields in U.S. West - typically 400 to 800 m in diameter • Landsat satellites provide 16 day repeat imaging -- sufficient for water consumption estimation • Landsat 4 & 5 TM’s provided 120 m thermal images for a single thermal band • Landsat 7 ETM+ provided 60 m thermal images for a single thermal band • A two band instrument will enable atmospheric correction so that more accurate surface temperatures can be derived. 4th Global Vegetation Workshop
Landsat Science Team: Current Working Groups (issues) • Future Missions • Recommendations for future missions - standards- requirements • What constitutes “operational”? • Long Term Goals and Purpose of Landsat Missions (Climate emphasis - land cover ECV) • Data Gap Working Group • Recommendations for an operational plan for the USGS to acquire moderate resolution data during a data gap • Global Consolidated Landsat Archive • More images outside the US Archive than within • Considerable overlap, but difficult to resolve • Provide guidance on priorities 4th Global Vegetation Workshop
Outstanding Issues • Surface Reflectance and Temperature • Recommendations for standard products • Need derived products • Carbon Mapping and Monitoring • White paper on state-of-the-art • Operational land cover change monitoring • Definition and implementation of a standard product • Cloud screening the archive • Routinely cited as the primary impediment to more automated use of Landsat imagery over large areas/multiple time periods • Reconstructing the history of the surface of Earth in the satellite era • A community agenda • Continuity • Behind in authorizing and building Landsat 9; community advocacy is needed • Definition of longer term sensing scenarios • What should happen after L9? 4th Global Vegetation Workshop
Summary • Good progress towards implementation of the LDCM as a free-flyer - Program has advanced to Phase B • Ball Aerospace Technology Corporation is building the OLI • OLI Critical Design Review successfully conducted in Oct., 2008 • Atlas V launch vehicle was selected in Oct., 2007 • General Dynamics Advanced Information Systems awarded spacecraft contact in April, 2008 - SRR competed; PDR scheduled in March • Mission Operations Element contract awarded to The Hammers Company in Sept., 2008 • Ground system development underway at USGS EROS • Preliminary Design Review scheduled for September, 2009 • Launch readiness date rescheduled from July, 2011 to December, 2012 • TIRS implementation remains to be determined • Successful TIRS Preliminary Design Review conducted May 27 - 28, 2009 • The Mission Preliminary Design Review scheduled for July 14 - 16 • Leads to Fall Key Decision Point - C (KDP-C) review and authorization to proceed to Phase C - Final Design and Fabrication Phase • New bands, Free data policy, Top quality data • is Landsat: resolutions, ground segment, archive, global coverage, LTAP…….. 4th Global Vegetation Workshop