Building False-Color Images of Earth

Terra's sensors are not actively scanning the surface of our planet. Rather, they are designed much like cameras to receive and detect sunlight that is reflected, and heat that is emitted, from the Earth. But Terra's sensors are sensitive to wavelengths of electromagnetic energy (infrared light and heat) that our eyes cannot see. In order for us to make images that allow our eyes to interpret Terra's data, we must assign colors (red, green, and blue) to these wavelengths that we otherwise couldn't see. We call the resulting pictures "false color images." These images allow us to interpret parameters of change on Earth like sea surface temperature (top frame), land cover changes (middle frame), rates of vegetative productivity (bottom frame).

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Reto Stockli, NASA GSFC

Published December 7, 1999
Data acquired December 7, 1999