Nov. 20, 2006 -- The European Space Agency ESA has supplied the satellite-map browser Google Earth with an additional layer of content. Via the menu item "Featured Content" users can now, guided by ESA logos sprinkled all over the globe, call up 130 additional satellite images of natural phenomena and monuments built by humans. Relevant items of information appear below the images, which can moreover be downloaded in two different quality grades.
The images of the collection come from the ESA satellites Envisat (the largest environmental satellite ever built), ERS (European Remote Sensing Satellite) and Proba (Project for On-Board Autonomy). Envisat was launched into orbit in 2002 and collects data with the help of its three imaging sensors ASAR (Advanced Synthetic Aperture Radar), MERIS (Medium Resolution Imaging Spectrometer) and AATSR (Advanced Along-Track Scanning Radiometer).
The radar instrument ASAR maps dry land, provides ice and wave profiles, monitors land use and types of vegetation and measures a variety of terrestrial features. MERIS takes pictures of the surface of the earth and of clouds. It operates in the visible-light and part of the infrared spectrum. The AATSR sensor scans dry land and bodies of water for sources of fire, measures water temperatures and the spread of vegetation in certain areas.
The function "Featured Content" was introduced into Google Earth in September and offers content providers such as ESA the opportunity to furnish material on outstanding natural and artificial phenomena as well as scientific items of information. The featured content providers currently include, among others, the United Nations Environmental Program (UNEP), National Geographic Magazine, Discovery Networks World Tour and the Jane Goodall Institute. (Robert W. Smith) / (jk/c't)
