Color enhanced infrared picture.
Mapping of shown color to IR wavelength: red = 800nm, blue = 900nm
Original data: Opportunity, Sol 616
Picture and discovery: Norbert Gasch
Seen through infrared filters, those gravel stones, all equal in visible light, show obvious differences in color. Some show strong reflections of infrared light with wavelengths around 800nm, some other with 900nm, as shown in the image on the left.
The cause for these color differences is not known yet.
On Earth, we can observe similar effects on infrared pictures of plants
where this observation is used to characterize different types of vegetation by
remote sensing though satellite infrared pictures.
The next picture shows the same area in visible light as a human on Mars would see it himself.
Same color differences on "blueberries":
Discussion about Sol 645 image
Source of original data: NASA/JPL MER Raw Image Archive
|© Holger Isenberg
last modified: 11/20/2005|
published on: 11/3/2005