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Landsat Data Continuity Missionand
Beyond
Mike Wulder
On behalf ofLandsat Science Team
LDCM SRR/MDR/PNAR 22-24 April 2008
4th Global Vegetation WorkshopJune 18, 2009
June 18, 2009 4th Global Vegetation Workshop 2
July 5, 1973 August 13, 1984 June 30, 2000
Landsat’s role in understanding a changing Earth
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.
June 18, 2009 4th Global Vegetation Workshop 3
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
June 18, 2009 4th Global Vegetation Workshop 4
36+ Years of Continuous Landsat Global 36+ Years of Continuous Landsat Global Land ObservationLand 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/
June 18, 2009 4th Global Vegetation Workshop 5
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.
June 18, 2009 4th Global Vegetation Workshop 6
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
June 18, 2009 4th Global Vegetation Workshop 7
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.
June 18, 2009 4th Global Vegetation Workshop 8
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)
June 18, 2009 4th Global Vegetation Workshop 9
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.
June 18, 2009 4th Global Vegetation Workshop 10
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
June 18, 2009 4th Global Vegetation Workshop 11
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
June 18, 2009 4th Global Vegetation Workshop 12
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
LDCM at KDP-B
June 18, 2009 4th Global Vegetation Workshop 14
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
June 18, 2009 4th Global Vegetation Workshop 16
Operational Land Imager (OLI)
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)
Contract awarded to Ball Aerospace Technical Corp. (BATC) July 2007Critical Design Review Completed Oct. 2008
Courtesy of BATC
June 18, 2009 4th Global Vegetation Workshop 22
Launch Vehicle
In September 2007, the Atlas V 401 launch vehicle was selected for LDCM by the Kennedy Space Center.
June 18, 2009 4th Global Vegetation Workshop 23
LDCM Spacecraft
Contract awarded to General Dynamics Advanced Information Systems (GDAIS) in April 2008
Courtesy of GDAIS
June 18, 2009 4th Global Vegetation Workshop 24
LDCM Spacecraft
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
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
GUIDANCE, NAVIGATION & CONTROL• 2 of 3 star trackers active• High precision IRU• Honeywell reaction wheels• SADA with damper• 3-axis stabilized• Zero momentum biased
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)
PROPULSION• Hydrazine blow-down propulsion
module• Eight 22N Redundant Thrusters
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
Courtesy of GDAIS
June 18, 2009 4th Global Vegetation Workshop 29
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.”
June 18, 2009 4th Global Vegetation Workshop 30
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
June 18, 2009 4th Global Vegetation Workshop 31
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.
LDCM Thermal Requirements
June 18, 2009 4th Global Vegetation Workshop 35
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
June 18, 2009 4th Global Vegetation Workshop 36
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?
June 18, 2009 4th Global Vegetation Workshop 37
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……..