Satellite Remote Sensing SPOT
The SPOT constellation of satellites currently consists of SPOT 1, SPOT 4, and SPOT 5. The SPOT satellites have superior resolution and revisit times compared to Landsat, making them better suited to tasks such as mapping and disaster monitoring. In addition, the SPOT satellites can take stereo pairs of images to allow measurement of the three- dimensional surface of the Earth. SPOT 5 is the most advanced and flexible commercially accessible remote sensing satellite. It operates in a range of different modes and can achieve 2.5 metre resolution, almost (but not technically) high-resolution, but unlike very high-resolution satellites, SPOT images cover a large footprint of approximately 60 x 60km.
SPOT satellites produce multi-spectral images with three (SPOT 1) or four (SPOT 4 and 5) spectral bands. The range of resolutions (20, 10, 5, and 2.5 metres) makes SPOT images useful for mapping at all scales between 1:100 000 and 1:10 000.
Because there are three SPOT satellites, and all can be tilted to take images away from the orbital path, SPOT satellites can image any location on the Earth’s surface once a day. No other medium or high-resolution satellite constellation has this ability, which is particularly useful in cloudy regions, where opportunities for acquiring cloud-free images are far between.
Specifications:
| Resolution: | Panchromatic/Mono (black and white) 10, 5 or 2.5 metres
Multi-spectral (colour) 20 or 10 metres |
| Bands: | Four multi-spectral: Blue, Green, Red, Near Infra-red, Shortwave infra-red |
| Revisit cycle: | approximately 2 to 3 days depending upon latitude and viewing angle |
| Image Size: | 60 x 60 km |