Here's a super-closeup of the Martian dunes I showed you earlier here:
https://plus.google.com/u/0/117663015413546257905/posts/Pjn9gYrQZp8
The dark stuff seems to be material falling down the dunes. Astronomer Candy Hansen writes:
"In the subimage falling material has kicked up a small cloud of dust. The color of the ice surrounding adjacent streaks of material suggests that dust has settled on the ice at the bottom after similar events. Also discernible in this subimage are polygonal cracks in the ice on the dunes (the cracks disappear when the ice is gone)."
I think you need to download the picture here to really see those polygonal cracks. Then they're easy to see.
#astronomy
https://plus.google.com/u/0/117663015413546257905/posts/Pjn9gYrQZp8
The dark stuff seems to be material falling down the dunes. Astronomer Candy Hansen writes:
"In the subimage falling material has kicked up a small cloud of dust. The color of the ice surrounding adjacent streaks of material suggests that dust has settled on the ice at the bottom after similar events. Also discernible in this subimage are polygonal cracks in the ice on the dunes (the cracks disappear when the ice is gone)."
I think you need to download the picture here to really see those polygonal cracks. Then they're easy to see.
#astronomy
