ASTER is one of the five state-of-the-art instrument sensor systems on-board Terra a satellite launched in December 1999. It was built by a consortium of Japanese government, industry, and research groups. ASTER monitors cloud cover, glaciers, land temperature, land use, natural disasters, sea ice, snow cover and vegetation patterns at a spatial resolution of 90 to 15 meters. The multispectral images obtained from this sensor have 14 different colors, which allow scientists to interpret wavelengths that cannot be seen by the human eye, such as near infrared, short wave infrared and thermal infrared.
ASTER is the only high spatial resolution instrument on Terra that is important for change detection, calibration and/or validation, and land surface studies. ASTER data is expected to contribute to a wide array of global change-related application areas, including vegetation and ecosystem dynamics, hazard monitoring, geology and soils, land surface climatology, hydrology, land cover change, and the generation of digital elevation models (DEMs). Satellite Imaging Corporation (SIC) is an official distributor for ASTER Imagery through USGS.
For many image requests, a matching image can already be located in the archives of ASTER imagery from around the world. If no image data is available in the archives, new ASTER satellite image data can be acquired through a satellite tasking process. Besides providing image data, SIC performs many background tasks to ensure that we meet customer specifications and time schedules. Our company:
ASTER Satellite System: Sensor Characteristics
|Launch Date||18 December 1999 at Vandenberg Air Force Base, California, USA|
|Equator Crossing||10:30 AM (north to south)|
|Orbit||705 km altitude, sun synchronous|
|Orbit Inclination||98.3 degrees from the equator|
|Orbit Period||98.88 minutes|
|Grounding Track Repeat Cycle||16 days|
|Resolution||15 to 90 meters|
The ASTER instrument consists of three separate instrument subsystems:
VNIR (Visible Near Infrared), a backward looking telescope which is only used to acquire a stereo pair image
SWIR (ShortWave Infrared), a single fixed aspheric refracting telescope
TIR (Thermal Infrared)
ASTER high-resolution sensor is capable of producing stereoscopic (three-dimensional) images and detailed terrain height models. Other key features of ASTER are:
ASTER has 14 bands of information. For more information, please see the following table:
|Cross Track Pointing||± 318km (± 24 deg)||± 116km (± 8.55 deg)||± 116km (± 8.55 deg)|
The VNIR subsystem operates in three spectral bands at visible and near-infrared wavelengths, with a resolution of 15 meters. A comparison with the panchromatic 15m band on the LANDSAT 7 ETM+ data shows that ASTER imagery is better both spatially and spectrally.