12th May 2015 Sol 983

A stunning image of sunset over the Gale Crater Rim!  The sort of long wavelength scattering so characteristic of our Earth’s red sunsets has not occurred.

Ehlers et al. 2014 Applied Optics, who studied this strange effect says: ‘Unlike Earth, the atmosphere of Mars is dominated by micron-size dust aerosols, and the sky during sunset takes on a bluish glow.  … Our findings show that while wavelength selective extinction can cause the sun’s disk to appear blue, the color of the glow surrounding the sun as observed from Mars is due to the dominance of near-forward scattering of blue light by dust particles… ‘

and see:

http://mars.jpl.nasa.gov/msl/news/whatsnew/index.cfm?FuseAction=ShowNews&NewsID=1810