Delta de Ganges in color

2009/08/04 Lakar Iraizoz, Oihane - Elhuyar Zientzia

• Irudiak/Soinuak
• Fisika
• Astronomia

In the picture you can see the largest delta in the world, located in South Asia, between Bangladesh and India. It is an image made with the data collected by the satellite Envisat of the European Space Agency, specifically with the data collected by the radar called ASAR.

In fact, with the information collected by the radars one could not create an image with colors, since to create images with colors one would have to use visible spectrum waves and the radars use radio waves.

The radio waves collected by the ASAR radar, however, allow very varied compositions, as shown in the figure: the radar sent waves to Earth and the material of the Ganges delta collected the distribution of these waves. Since materials disperse waves differently depending on their composition, it is easy to express surface variations and assign each one a specific color.

Image courtesy of: ESA