3.2.5. SPOT

The SPOT range of satellites have been in operation since 1986. To date, seven SPOT satellites have been launched, all providing high spatial resolution images with a wide footprint of about 60×60 km. Table 3.3 provides the relevant details of the various missions. 

Table 3.3. Characteristics of SPOT satellites. Find here more details on: SPOT 1SPOT 2SPOT 3SPOT 4SPOT 5SPOT 6SPOT 7.
 

SPOT-1 to -3 had three multi-spectral bands (green, red, NIR) and one panchromatic band with spatial resolutions of 20 m and 10 m, respectively. A SWIR band was added to the multi-spectral bands of SPOT-4 and -5, while spatial resolution improved to 5 m with a 2.5 m panchromatic band. SPOT satellites operate with the pushbroom imaging design.

 Although spatial resolution has improved from 20 m (SPOT 1) to 1.5 m (SPOT 6/7), the footprint of SPOT 6/7 has remained the same. This is an important characteristic for smallholder agricultural applications compared to DigitalGlobe images, relatively large areas can be analyzed at a high spatial detail. Thus, in terms of spatial resolution, it may be cost-effective to use SPOT-6/-7 for agricultural management. However, depending on the specific use, spectral characteristics may have to be considered too. For example, WorldView-2 and -3 have more spectral bands than SPOT-6 and -7 (e.g., they include red-edge), which can benefit mapping the spatial distribution of different crop types.  

 All images acquired by SPOT-1 through to -5 are now accessible online in a Geostore catalogue which contains more than 30 million images at resolutions of between 20 m (SPOT-1) and 2.5 m (SPOT-5). SPOT-6/-7 data can be obtained from archives or by tasking. 

SPOT images have been useful in civilian and military mapping, agricultural applications, land planning, natural resource exploitation, 3D mapping (SPOT-5), maritime surveillance and environmental protection.