HiRISE has been monitoring this dune field since 2008, and it changes every year from gully erosion in the winter and blowing sand in the summer.
This cutout shows an especially large gully
. The bright white materials are seasonal frost, persisting on shaded slopes. ID
: 29 December 2019 altitude
: 252 km
#Mars #science #NASAtwitter
• right-click to copy link