1. Remote Sensing II Sensors Konari, Iran Image taken 2/2/2000
The Mand River and the small town of Konari nestle in the Zagros Mountains in western Iran.

2. Major Satellite Systems
High spatial resolution
Quickbird, IKONOS, OrbView-3, SPOT-5 PAN, IRS-P6
Medium spatial resolution
Landsat-5 TM, Landsat-7 ETM+, ASTER, SPOT
Low spatial resolution
MODIS, ENVISAT, GOES, AVHRR, MSS

3. Sensor types Pushbroom (along track) vs. Whiskbroom (across track)
SPOT and IKONOS: Pushbroom
Landsat: Whiskbroom
Pushbroom scanners generally have higher radiometric resolution because they have longer “dwell time” than across-track scanners, which move laterally across landscape as they also move forward

4. Orbits Most of these satellites are in sun-synchronous orbit
The satellite passes over the same part of the Earth at roughly the same local time each day
Its “inclination” is about 8 degrees off of polar orbit
The fact that the earth is not a perfect sphere makes the orbital plane rotate slowly around the earth (this would not happen if it were perfectly polar)

5. Orbits
Slow motion of orbital plane matches the latitudinal motion of the sun in the sky over the year
Maintains similar sun angles along its ground trace for all orbits
That means that a given location always gets the same mean sunlight angle, which provides consistent lighting

6. LANDSAT First started by NASA in 1972; later turned over to NOAA
Since 1984 satellite operation and data handling are managed by a commercial company EOSAT
LANDSAT-7 launched in 1999; developed scan line error in 2003
Only 5 is still working; outdated

7. Thematic Mapper spectral resolution
LANDSAT
Several sensor types
Multi-spectral scanner (MSS) – LANDSAT-1 through LANDSAT-5
Thematic Mapper (TM) – LANDSAT-4 and -5
Enhanced Thematic Mapper (ETM+) – LANDSAT-7
Thematic Mapper spectral resolution

8. LANDSAT ETM+
Slightly different bands than TM; otherwise similar, stressing continuity
Check out the movie

9. LANDSAT TM Applications
Band
Nominal Spectral location
Applications 1
Blue
Water body penetration, soil-water discrimination, forest type mapping, cultural feature ID 2
Green
Green reflectance peak of veg, for veg ID and assessment of vigor, cultural feature ID 3
Red
Chlorophyll absorption region, plant species differentiation, cultural feature ID 4
Near infrared
Veg types, vigor and biomass content, delineating water bodies, soil moisture assessment 5
mid infrared ( mm)
Veg moisture, soil moisture, diff of soil from clouds 6
Thermal infrared
Veg stress analysis, soil moisture, thermal mapping 7
mid infrared( mm)
Discriminating mineral and rock types, veg moisture

10. LANDSAT 16 day repeat cycle
Orbit takes about 99 minutes (14.5 per day)
Follows earth’s rotation so crosses the equator at the same time (~10 a.m.)
183 km swath width; 170 km data frame
233 orbits per 16 days

11. LANDSAT
Extensive archive distributed by the Earth Resource Observation System (EROS) Data Center of the US Geological Survey
Available at

12. LANDSAT

13. SPOT
Satellite Pour l'Observation de la Terre operated by the French Space Agency, Centre National d'Etudes Spatiales (CNES).
5 satellites launched (several are still operational)
Each has 2 High Resolution Visible (HRV) sensors constructed with multilinear array detectors, or “Pushbroom scanners” that record multispectral data along a wide swath

14. SPOT
The position of each HRV unit can be changed by ground control to observe a region of interest that is at an oblique angle to the satellite—up to ±27º relative to the vertical.
Off-nadir viewing allows for acquisition of stereoscopic imagery (because of the parallax created) and provides a shorter revisit interval of 1 to 3 days.
Any point on 95% of the Earth can be imaged any day by one of the satellites

15. SPOT
Two modes: panchromatic and multispectral

16. SPOT

17. IKONOS Developed by Space Imaging, launched 1999
Has sun-synchronous orbit and crosses equator at 10:30 AM
Highly maneuverable: can point at a new target and stabilize itself in seconds, enabling it to follow meandering features
The entire spacecraft moves, not just the sensors, allowing data collection at angles of up to 45°from nadir (allows for side-by-side and fore-aft stereo imaging)
Employs a linear array scanner (“pushbroom”)
11 km swath width; customizable

18. IKONOS
1m multispectral image of Dubai

19. Worldview-2 DigitalGlobe satellite launched in October, 2009
Very agile, and has increased on-board storage
High altitude (770 km), sun synchronous orbit
Short revisit time
8 spectral bands
16.4 km swath width

20. Worldview-2
1m multispectral image of Dubai

21. Panchromatic Film Source VT Orthophotos Sensor Film Spatial Resolution
Spectral Coverage
Radiometric Resolution
8-bit 1

22. Color Film Source Duchess County Orthophotos Sensor Film
Spatial Resolution
0.62ft
Spectral Coverage
Radiometric Resolution
8-bit 1 1 1

23. CIR Digital Source Emerge Orthophotos Sensor Digital Camera
Spatial Resolution
0.6m
Spectral Coverage
Radiometric Resolution
8-bit 1 1 1

24. Oblique Imagery
64ft
38ft
Imagery © Pictometery, 2007

25. Tsang Po River, Tibet – 1m Panchromatic
IKONOS-2
Spatial Resolution
Pan: 1m
MS: 4m
Spectral Coverage
Radiometric Resolution
11-bit
Temporal Resolution
3-4 days
Scene Size
13 x 13km 1 1 1 1 1
Source: Space Imaging
Tsang Po River, Tibet – 1m Panchromatic

26. Woodstock, VT– 1m Panchromatic Waitsfield, VT– 4m Multispectral
IKONOS-2
© Space Imaging
© Space Imaging
Woodstock, VT– 1m Panchromatic
Waitsfield, VT– 4m Multispectral

27. Manhattan, NY – 0.61m Multispectral
Quickbird-2
Spatial Resolution
Pan: 61cm - 72cm
MS: 2.44m – 2.88m
Spectral Coverage
Radiometric Resolution
11-bit
Temporal Resolution
3-4 days
Scene Size
32 x 32km 1 1 1 1 1
Source: DigitalGlobe
Manhattan, NY – 0.61m Multispectral

28. Mauritius – 2.44m Multispectral Boston, MA – 0.61m Panchromatic
Quickbird-2
Source: DigitalGlobe
Mauritius – 2.44m Multispectral
Source: DigitalGlobe
Boston, MA – 0.61m Panchromatic

29. Deepwater Horizon clean up– 0.5m Multispectral
Worldview-2
Spatial Resolution
Pan: 50cm
MS: 1.8m – 2.4m
Spectral Coverage
Radiometric Resolution
11-bit
Temporal Resolution
days
Scene Size
16 x 16km 1 1 1 1 1 1 1 1
Source: DigitalGlobe
Deepwater Horizon clean up– 0.5m Multispectral

30. Worldview-2 Boulder, CO – 0.5m Multispectral
Source: DigitalGlobe
Source: DigitalGlobe
Boulder, CO – 0.5m Multispectral
Deepwater Horizon – 0.5m Multispectral

31. Brattleboro, VT – 30m Multispectral
Landsat-7
Spatial Resolution
Pan: 15m
MS: 30m/60m
Spectral Coverage
Radiometric Resolution
8-bit
Temporal Resolution
16 days
Scene Size
185 x 185km 1 1 1 1 1 2 1
Brattleboro, VT – 30m Multispectral

32. Landsat-7 Harriman Reservoir, VT – 30m Multispectral
St. Albans Bay, VT – 30m Multispectral

33. ASTER Spatial Resolution MS: 15m/30m/90m Spectral Coverage
Radiometric Resolution
8-bit/12-bit
Temporal Resolution
Varies
Scene Size
60x 60km 1 1 1 6 5
Boston, MA – 90m Thermal

34. ASTER Winooski River, VT – 15m Multispectral
Otter Creek, VT – 15m Multispectral