The GOES-12 satellite sits at 75 degrees west longitude at an altitude of 36,000 kilometers over the equator, in geosynchronous orbit. At this position its Imager instrument takes pictures of cloud patterns in several wavelengths for all of North and South America, a primary measurement used in weather forecasting. Every three hours the Imager takes a picture of the full disk of the Earth. This animation shows a sequence of these full disk images in the visible wavelengths, 0.52 to 0.72 microns, during the period that Hurricane Katrina passed through the Gulf of Mexico. This wavelength band clearly shows the day-night cycle since the Earth is dark at night in the visible wavelengths.
GCMD keywords can be found on the Internet with the following citation:
Olsen, L.M., G. Major, K. Shein, J. Scialdone, S. Ritz, T. Stevens, M. Morahan, A. Aleman, R. Vogel, S. Leicester, H. Weir, M. Meaux, S. Grebas, C.Solomon, M. Holland, T. Northcutt, R. A. Restrepo, R. Bilodeau, 2013. NASA/Global Change Master Directory (GCMD) Earth Science Keywords. Version 220.127.116.11.0