Long Term Data Preservation and applications of Nimbus 7 - Coastal Zone Color Scanner dataset

Imaging in remote sensing can be done both from satellite and aircraft platforms. Their sensors are similar although differences in the attitude and stability can lead to very different image properties.
There are essentially two classes of Remote Sensing satellite-programs: satellites that are at geostationary altitudes (GEO) above the earth which are generally used for meteorological information, climate and weather studies, and those which orbit much closer to the surface and that are generally used for land and oceanographic observations. Usually, the low earth orbiting satellites are in a sun-synchronous orbit, in that their orbital plane precesses around the earth at the same rate that the sun appears to move across the earth’s surface. In this manner the satellite acquires data at about the same local time on each orbit.
Low-earth orbiting satellites (LEO) can also be used for meteorological studies.
The major distinction in the image data that satellites orbiting in LEO and GEO provide generally lies in the spatial resolutions available. Whereas data acquired for earth resources purposes generally has pixel sizes of less than 100 m, that used for meteorological purposes (both at geostationary and lower altitudes) has a much coarser pixel, often of the order of 1 km.
The imaging technologies utilized in satellite programs have ranged from traditional cameras to mechanical scanners that record images of the earth’s surface by moving the instantaneous field of view (IFOV) of the instrument across the earth’s surface to record the upwelling energy.
Some weather satellites scan the earth’s surface using the spin of the satellite
itself while the sensor’s pointing direction is varied (at a slower rate) along the axis of the satellite.
A more common image recording mechanism has been to carry a mechanical scanner that records at right angles to the direction of the satellite motion to produce raster-scans of data. The forward motion of the vehicle then allows an image strip to be built up from the raster-scans.
More recent technology utilizes a push-broom mechanism in which a linear imaging array with sufficient detectors is carried on the satellite, normal to the satellite’s direction of motion, such that each pixel can be recorded individually. The forward motion of the satellite then allows subsequent pixels to be recorded along the satellite travel direction. As might be expected, the time over which the energy emanating from the earth’s surface per pixel is larger with push broom scanning than for the mechanical scanners, generally allowing finer spatial resolutions to be achieved.
Aircraft scanners operate with essentially the same principles as those found on satellites. [...]