Indonesian islands

This image from the Envisat satellite is dominated by the Indonesian islands of Bali, Lombok and Sumbawa. Bali's central mountains include peaks that reach over 3000 m, including an active volcano visible on the right side of the island. Strong reflections of the radar signal used to produce this image appear like specks of light. They are mainly detectable in the southern part of the island, and are particularly concentrated around the provincial capital city of Denpasar. This is the typical appearance of built-up areas in radar images, owing to the multiple reflection of the radar beam by buildings and especially metal constructions.

This image is a compilation of three passes by Envisat’s radar on 20 June, 19 August and 17 December 2011. Each is assigned a colour (red, green and blue) and combined to produce this representation. The colours reveal changes in the surface between Envisat’s passes.