IKONOS High Resolution Multispectral Scanner Sensor Characteristics

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1 High Spatial Resolution and Hyperspectral Scanners

2 IKONOS High Resolution Multispectral Scanner Sensor Characteristics Launch Date View Angle Orbit 24 September 1999 Vandenberg Air Force Base, California, USA Along track and across track pointing 98.1 degree, sun synchronous Orbit Time Around the Earth Altitude 98 minutes 681 kilometers Resolution Nadir: 0.82 meters panchromatic 3.2 meters multispectral 26 Off-Nadir 1.0 meter panchromatic 4.0 meters multispectral Image Swath Equator Crossing Time Revisit Time Dynamic Range Image Bands 11.3 kilometers at nadir 13.8 kilometers at 26 off-nadir Nominally 10:30 a.m. solar time Approximately 3 days at 40 latitude 11-bits per pixel Panchromatic, blue, green, red, near IR

3 IKONOS Spectral Bands wavelength (µm) Ground (Pixel) Resolution 1 (blue) m 2 (green) m 3 (red) m 4 (NIR) m Panchromatic m

4 Ejemplo Geoespacial

5 IKONOS March 9, 2004 IKONOS August 31, 2005 New Orleans, LA Pre and Post Hurricane Katrina

6 Spring 2001 leaf off IKONOS of Northern Maine RGB-4(NIR), 3(Vis Red), 2(Vis. Green) multipectral image - 4m pixel

7 Heavy Partial Harvest Munsungan Lake, Maine IKONOS June m Multispectral (RGB-432)

8 IKONOS (4 m) near Charleston, South Carolina. Water Tupelo & Bald Cypress trees, and a class of the two (mixed), attempted computer classification

9 Quickbird High Resolution Multipectral 2.5m resolution RGB 432 CIR Composite Image (NIR, red, green)

10 Quickbird RGB432 (CIR) RGB 321 (True Color)

11 ASTER 15m NASA EOS-AM TERRA satellite platform

12 Hyperspectral Satellite Sensor Systems Recent advances in remote sensing and geographic information has led the way for the development of hyperspectral (many narrow wavebands) sensors. Hyperspectral remote sensing, also known as imaging spectroscopy, is a relatively new technology that is currently being investigated by researchers and scientists with regard to the detection and identification of minerals, terrestrial vegetation, and man-made materials and backgrounds. The concept of hyperspectral remote sensing began in the mid-80's and to this point has been used most widely by geologists for the mapping of minerals. Actual detection of materials is dependent on the spectral coverage, spectral resolution, and signal-to-noise of the spectrometer, the abundance of the material and the strength of absorption features for that material in the wavelength region measured.

13 Hyperspectral Cube Hyperspectral imagery is typically collected (and represented) as a data cube with spatial information collected in the X-Y plane, and spectral information represented in the Z- direction.

14 Hyperspectral data sets are generally composed of about 100 to 200 spectral bands of relatively narrow bandwidths (5-10 nm), whereas, multispectral data sets are usually composed of about 5 to 10 bands of relatively large bandwidths ( nm). Applications There are many applications which can take advantage of hyperspectral remote sensing. Atmosphere: water vapor, cloud properties, aerosols Ecology: chlorophyll, leaf water, cellulose, pigments, lignin Geology: mineral and soil types Coastal Waters: chlorophyll, phytoplankton, dissolved organic materials, suspended sediments Snow/Ice: snow cover fraction, grain size, melting Biomass Burning: sub-pixel reflectance, smoke Commercial: mineral exploration, agriculture and forest production

15 Hyperspectral Spectral Reflectance Graph for Wetland/Marsh Species

16 EO-1 Hyperion Satellite (medium spatial resolution) The National Aeronautics and Space Administration (NASA) EO-1 satellite was launched on November 21, EO-1 Sensor Hyperion is a hyperspectral sensor which offers data in 220 spectral bands. EO-1/ Hyperion offer the highest available spectral resolution in the field of satellite-borne RS systems. EO-1 Satellite Sensors Specifications: Sensors: Hyperspectral Ground resolution of each band: 30 m Spectral Range: µm Channels: 220 bands Swath Widths 7.6 km Revisit Frequency 16 d

17 Hyperspectral Hyperion (NASA) satellite sensor Color Infrared Composite (RGB )