Introduction to Satellite Remote Sensing
1 Remote sensing of the Earth from orbital altitudes was recognized in the mid-1960’s as a potential technique for obtaining information important for the effective use and conservation of natural resources.
The studies began when the Tiros satellites (1960) provided man’s first synoptic view of the Earth’s weather systems.
The manned Gemini and Apollo Programs (1962-1972) led to further consideration of space-age remote sensing for study of the planet Earth.
The Earth Resources Technology Satellite (ERTS), later designated Landsat, provided repetitive multispectral observation of the Earth.
2 Earth Rising
The photo was taken by astronaut William Anders from Apollo 8 in December 24, 1968.
As Apollo 8 raced backward away from the Earth, Anders snapped a picture of “a fist-sized fuzzy little ball of color against the immense backdrop of space.” (Parker, RI News, Providence Journal, Oct. 24, 2010)
(Anders lived in Barrington for about 5 years in 1980s as an executive at RI-based Textron. He was inducted Into Rhode Island Aviation Hall of Fame for his role on Apollo 8.)
Earth rising over the lunar surface, one of the most famous images of the 20th century.
This is how Anders saw the image. NASA
3 Skylab, the largest manned space station placed at low Earth orbit at the time, was lunched in May 14, 1973 and carried into space the Earth Resources Experiment Package (EREP).
EREP was designed to view the Earth with sensors that recorded data in visible, infrared, and microwave spectral regions. EREP became another step in space exploration by testing the high spatial resolution camera systems with film return capability, narrow frequency bandwidth scanner systems in the visible through thermal-infrared spectral region, and initial use of active and passive microwave systems in Earth resources surveys.
A significant feature of EREP was the use of man to operate the sensors in a laboratory fashion.
Landsat represents the world's longest (since 1972) continuously acquired collection of space-based land remote sensing data.
The instruments on the Landsat satellites have acquired millions of images. The images, archived in the United States and at Landsat receiving stations around the world, are a unique resource for global change research and applications in agriculture, geology, forestry, regional planning, education and national security.
4 Landsat-1, 2, 3 Landsat Missions
Landsat 1 (07/12/1972 - 01/06/1978) - RBV, MSS (80m) Landsat 2 (01/22/1975-07/27/1983) - RBV, MSS (80m) Landsat 3 (03/05/1978-09/07/1983) - RBV, MSS (80m) Landsat 4 (07/16/1982 - ) - MSS, TM (30m, 120m TIR) Landsat 5 (03/01/1984 - ) - MSS, TM (30m, 120m TIR) Landsat 6 (10/05/1993): ETM ??? Landsat 7 (04/23/1999 - ) - ETM+ (30m, 60m TIR, 15m Pan) Landsat-4, 5 Landsat 8 (February 11, 2013) – OIL, TIRS (30m, 100m TIRS 15m Pan )
ETM+: Enhanced Thematic Mapper Plus MSS: Multispectral Scanner
OLI: Operational Land Imager Landsat-7 Pan: Panchromatic RBV: Return Beam Vidicon Camera TIR: Thermal Infrared Landsat-8 TIRS: Thermal Infrared Sensor TM: Thematic Mapper
Spectral Cover of Band 1: 0.45-0.52m (blue). Landsat Sensors Provide increased penetration of water (TM, ETM+) bodies, as well as supporting analysis of land use, soil, and vegetation characteristics.
Band 2: 0.52-0.60m (green). This band spans the region between the blue and red chlorophyll absorption bands and therefore corresponds to the green reflectance of healthy vegetation.
Band 3: 0.63-0.69m (red). This is the red chlorophyll absorption band of healthy green vegetation and represents one of the most important bands for vegetation discrimination.
5 • Band 4: 0.76-0.90m (reflective infrared). This band is responsive to the Spectral Cover of amount of vegetation biomass present in Landsat Sensors the scene. It is useful for crop (TM, ETM+) identification and emphasizes soil-crop and land-water contrasts. • Band 5: 1.55-1.75m (mid-infrared) This band is sensitive to the amount of moisture in plants and therefore useful in crop draught and in plant vigor studies. • Band 6: 10.4-12.5m (thermal infrared) This band measures the amount of infrared radiant flux emitted from surface. • Band 7: 2.08-2.35m (mid-infrared) This is an important band for the discrimination of geologic rock formation. It is effective in identifying zones of hydrothermal alteration in rocks.
Comparison of Landsat Sensors
Thematic Mapper Enhanced Thematic Multispectral (TM) Landsat 4 and 5 Mapper Plus (ETM+) Scanner (MSS) Landsat 7 Landsat 1-5 Spectral 1. 0.45-0.52 (B) 1. 0.45-0.52 0.5-0.6 (green) Resolution 2. 0.52-0.60 (G) 2. 0.53-0.61 0.6-0.7 (red) (m) 3. 0.63-0.69 (R) 3. 0.63-0.69 0.7-0.8 (NIR) 4. 0.76-0.90 (NIR) 4. 0.78-0.90 0.8-1.1 (NIR) 5. 1.55-1.75 (MIR) 5. 1.55-1.75 7. 2.08-2.35 (MIR) 7. 2.09-2.35 6. 10.4-12.5 (TIR) 6. 10.4-12.5 8. 0.52-0.90 (Pan) Spatial 30 x 30 15 x 15 (Pan) 79 x 79 Resolution 120 x 120 (TIR) 30 x 30 (meter) 60 x 60 (TIR) Temporal 16 16 18 (Landsat 1,2,3) Resolution (revisit in days) Spatial 185 x 185 183 x 170 185 x 185 coverage (km) Altitude (km) 705 705 915 (Landsat 1,2,3)
6 Landsat-7 ETM+ Data of Providence
Landsat-7 Panchromatic Data (15 m) Landsat-7 ETM+ Data (30 m), Bands 3, 2, 1 in RGB
Landsat-7 ETM+ Data (30 m), Bands 4, 3, 2 in RGB Landsat-7 ETM+ Data (30 m), Bands 4, 5, 3 in RGB
Landsat-8 and Sensors:
7 Landsat-8 Sensors: Operational Land Imager (OLI) OLI spectral bands ETM + spectral bands # Band width GSD (m) # Band width GSD (m) (μm) (μm) 1 0.433–0.453 30 2 0.450–0.515 30 1 0.450–0.515 30 3 0.525–0.600 30 2 0.525–0.605 30 4 0.630–0.680 30 3 0.630–0.690 30 5 0.845–0.885 30 4 0.775–0.900 30 6 1.560–1.660 30 5 1.550–1.750 30 7 2.100–2.300 30 7 2.090–2.350 30 8 0.500–0.680 15 8 0.520–0.900 15 9 1.360–1.390 30
Landsat-8 Sensors: Operational Land Imager (OLI)
8 Landsat-8 Sensors: Thermal Infrared Sensor (TIRS)
TIRS Sensors measure land surface temperature in two thermal bands.
Band # Center wavelength (μm) Spatial resolution (m)
10 10.6-11.2 100 11 11.5-12.5 100
Example of Landsat 8 imagery (Fort Collins, Colorado, March 18, 2-13)
9 10 Rhode Island: Path 12/Row 31
11 Landsat Ground Stations
Collections of Landsat Images of the World
12 Mangroves in the Niger River Delta: 1990 Landsat Image
13 Mangrove Forests On Landsat Images
Over 100 kilometers crisscrossing streams and rivers of the Kibasira Swamp
14 Streams and rivers eroding the banks of the Rufiji river
Stiegler’s Gorge section of the Rufiji River
15 16 USGS EROS Data Center http://edcsns17.cr.usgs.gov/EarthExplorer/
USGS EROS Data Center http://eros.usgs.gov/#/Remote_Sensing
17 TERRA (EOS AM) - Launched December 18, 1999 The following instruments fly on TERRA:
ASTER: Advanced Spaceborne Thermal Emission and Reflection Radiometer (15m - 3 bands in VNIR; 30m - 6 bands in SWIR; 90m - 5 bands in TIR)
MODIS: Moderate Resolution Spectroradiometer (0.4 - 14.4 m) (250m - 2 bands, 500m - 5 bands, 1000m - 29 bands)
CERES: Clouds and the Earth's Radiant Energy System MISR: Multi-angle Imaging Spectroradiometer MOPITT: Measurements of Pollution in the Troposphere.
Provisional Land Cover Product June 01
MODIS data from Jul 00– Jan 01
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18 The MODIS Global Vegetation Phenology product (MOD12Q2) provides estimates of the timing of vegetation phenology at global scales. As such, MOD12Q2 identifies the vegetation growth, maturity, and senescence marking seasonal cycles.
EO-1: successfully launched on November 21, 2000
ALI - Advanced Land Imager consists of a 15° Wide Field Telescope (WFT) and partially populated focal plane occupying 1/5th of the field-of-view, giving a ground swath width of 37 km.
Hyperion – Hyper-spectral sensors a grating imaging spectrometer having a 30 meter ground sample distance over a 7.5 kilometer swath and providing 10nm (sampling interval) contiguous bands of the solar reflected spectrum from 400-2500nm.
19 Hyperspectral data Hyperion sensor on board the EO-1 Satellite
Spectral profile in a single pixel location from 0.4 to 2.5 m at 10 nm interval for a continuous coverage over 220 bands
EO-1 launched November 21, 2000
EOS AM Constellation / Ground Tracks
20 SPOT satellites SPOT 5 was successfully launched on May 3, 2002
SPOT 4 - March 24, 1998
SPOT-4 VEGETATION SPOT 3 - Sept. 25, 1993
SPOT 2 - Jan. 22, 1990
SPOT 1 - Feb. 21, 1986
The SPOT Sensor
The position of each HRV entrance mirror can be commanded by ground control to observe a region of interest not necessarily vertically beneath the satellite. Thus, each HRV offers an oblique viewing capability, the viewing angle being adjustable through +/- 27degrees relative to the vertical.
Two spectral modes of acquisition are employed, panchromatic (P) and multispectral (XS). Both HRVs can operate in either mode, either simultaneously or individually.
21 SPOT 4-VEGETATION: This program marks a significant advance to monitor crops and the continental biosphere. The VEGETATION instrument flying on Spot 4 provides global coverage on an almost daily basis at a resolution of 1 kilometer, thus making it an ideal tool for observing long-term environmental changes on a regional and worldwide scale.
With a swath width of 2,250 kilometers, the VEGETATION instrument covers almost all of the globe's land masses while orbiting the Earth 14 times a day. Only a few zones near the equator are covered every day. Areas above 35°latitude are seen at least once daily.
Launched: September 24, 1999
Ground resolution: 1 meter panchromatic (0.45-0.90 m), 4 meters multispectral (same as Landsat TM bands 1 - 4) (Band 1: 0.45-0.52 m Blue) (Band 2: 0.52-0.60 m Green) (Band 3: 0.63-0.69 m Red) (Band 4: 0.76-0.90 m Near IR)
22 23 On October 19, 2001 DigitalGlobe launched the QuickBird 2 satellite.
24 September 3, 2003 QuickBird Satellite Panchromatic Images (0.6-m Spatial Resolution)
September 3, 2003 QuickBird Satellite True-color and Pseudo-color Images 2.5-m Spatial Resolution
Concept of Multispectral Or spectral resolution
25 Natural color, high-resolution DigitalGlobe satellite image featuring the Golden Gate Bridge and Toll Plaza.
Image collected March 7, 2010
GeoEye-1, a Google sponsored satellite, was launched September 6, 2008.
Camera Modes • Simultaneous panchromatic and multispectral (pan-sharpened) • Panchromatic only • Multispectral only
Resolution • 0.41 m / 1.34 ft* panchromatic • 1.65 m / 5.41 ft* multispectral
26 GeoEye's next satellite, GeoEye-2, is in a phased development process for an advanced, third-generation satellite capable of discerning objects on the Earth’s surface as small as 0.25-meter (9.75 inch) in size, due to launch in 2013.
Shuttle Radar Topography Mission (SRTM), February 11-22, 2000, obtained the high-resolution digital topographic database of the Earth
Mt. Kilimanjaro (5,895 m)
Tanzania/ Kenya Digital Elevation Model (DEM) in GIS Coastal Zone
27 SeaWiFS October 2001
SeaWiFS October 1997
Credit line for all images: Provided by the SeaWiFS Project, NASA/Goddard Space Flight Center and ORBIMAGE
Examples Of SeaWiFS Images
28 October 28, 2011
National Polar-orbiting Operational Environmental Satellite System (NPOESS) Preparatory Project, or NPP, satellite was launched successfully. This marks the start of the next generation of space-based weather and climate observations.
NPP becomes one of NASA’s newest eye in the sky to keep tabs on the ozone, improve hurricane science, and maintain steady records of the changing climate - and will fill the void if any of the current polar satellites should fail.
Satellites in Space?
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