OSIRIS-REx Vegetation Index of Earth with MapCam Color Image Overlaid

This vegetation index, created using images taken by OSIRIS-REx’s MapCam camera on Sept. 22, 2017, shows areas on Earth with abundant plant life.

The overlay fading in is a color composite image captured by MapCam the same day. The bright green areas have higher densities of trees and other plants, and the darker green areas have lower densities. Hawaii stands out against the Pacific Ocean in the middle of the image. Australia, New Zealand and Papua New Guinea are visible in the lower left, and parts of China, Japan and Korea appear in the upper left.

To produce the vegetation index, the OSIRIS-REx image processing team used images taken with MapCam’s red and near-infrared (w and x) filters and applied an algorithm to highlight areas where the ratio of infrared energy reflected back was higher, indicating the presence of plant life. Scientists use this type of index–called a normalized difference vegetation index or NDVI–to study changes and patterns in plant life on Earth’s surface. OSIRIS-REx is not expected to find any plant life on Bennu, but the mission’s image processing team plans to use similar techniques to identify other materials on the asteroid’s surface.

Date Taken: Sept. 22, 2017

Instrument Used: OCAMS (MapCam)

Credit: NASA/Goddard/University of Arizona