Four hasselblad cameras were installed in the same

Info icon This preview shows pages 7–13. Sign up to view the full content.

Four Hasselblad cameras were installed in the same platform and looking toward the same direction in order to take pictures at the same time for the same object. These multispectral pictures were digitized and used to develop image processing techniques that later were used with Landsat data. In the 70’s other sensors were developed to acquire images in other regions of the electromagnetic spectrum besides the visible, like the mid infrared and the thermal infrared. They had large field of view (in hundreds of kilometers). Such large scale cover was valuable for meteorology.
Image of page 7

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

8 In July 1972 NASA lunched the first “Earth Resources Technology Satellite” (ERTS-1). These multispectral data provided a better understanding of our planet, including land used and land cover, urban development, and Earth global processes. The name was later changed to LANDSAT and it has been a very successful long-term mission. The Ozone Hole over the Antarctica, discovered by British scientists, was confirmed by the Nimbus-7 Total Ozone Mapping Spectrometer (TOMS) launched in 1978. Since then, TOMS makes daily maps of global ozone concentration. TOMS data were used as scientific evidence in the First Protocol of Montreal, were 40 nations agreed to reduce the use of CFC’s in 50% for year 1999.
Image of page 8