HYPERION IMAGES AND THEIR UTILITY
The Hyperion instrument is a unique feature of the EO-1 mission. Hyperion is an experimental hyperspectral imager that can capture high resolution images of the earth surface in 242 contiguous spectral bands, of which 220 are unique (there are 22 overlaping bands). The Hyperion platform viz., EO-1 has an altitude of 705 km (same as Landsat), an inclination of 98.2 degrees, period of 99 mins and a repeat cycle of 16 days. It is inserted into an orbit flying in formation with the Landsat 7 satellite taking a series of the same images, and comparison of these "paired scene" images is one of the ways of evaluating Hyperion images.
The Hyperion instrument provides a new class of Earth observation data for improved Earth surface characterization. It is a science grade instrument with quality calibration based on heritage from the LEWIS Hyperspectral Imaging Instrument (HSI). The Hyperion capabilities provide resolution of surface properties into hundreds of spectral bands versus the ten multispectral bands flown on traditional Landsat imaging missions. Through these spectral bands, complex land eco-systems can be imaged and accurately classified.
The Hyperion is a push-broom imager with 242 bands having a width of approximately 10nm covering the spectrum from 400nm - 2400nm, with an absolute radiometric accuracy of 6%. The swath of a Hyperion image is about 7.6 km with a ground sample distance (GSD) of 30 m at 705 km altitude. The instrument can image a 100 km long strip per image The Hyperion telescope images the Earth onto a slit that defines the instantaneous field-of-view which is 0.6240 wide (i.e., 7.5 Km swath width from a 705 Km altitude) by 42.55 µradians (30 meters) in the satellite velocity direction. A dichroic filter in the system reflects the bands from 400 to 1,000nm to the Visible-Near Infra Red (VNIR) spectrometer, and transmits the band from 900 to 2,500nm to the Short-Wave Infra Red (SWIR) spectrometer. As a result, the VNIR and SWIR bands overlap from 900 to 1000nm, which allows cross calibration between the two spectrometers.
Of the 242 acquired bands, 70 bands from 356 – 1058 nm are acquired by the VNIR spectrometer while 172 bands from 852 – 2577 nm are acquired by the SWIR spectrometer.
UTILITY OF HYPERION IMAGES:
Hyperion images have wide ranging applications in mining, geology, forestry, agriculture, and environmental management. Detailed classification of land assets through the Hyperion will enable more accurate remote mineral exploration, better predictions of crop yield and assessments, and better containment mapping. There are many applications which can take advantage of Hyperion hyperspectral imagery:
Atmosphere: Water vapor, cloud properties, aerosols
Ecology: Chlorophyll, leaf water, cellulose, pigmemts, lignin
Geology: Mineral and soil types and forest production
Coastal Waters: Chlorophyll, phytoplankton, dissolved organic materials, suspended sediments
Snow/Ice: Snow cover fraction, grainsize, melting
Biomass Burning: Subpixel temperatures, smoke
Commercial: Mineral exploration, agriculture
This website is hosted by
Department of Geology
Aligarh Muslim University, Aligarh - 202 002 (India)