HiRISE images

A piece of Mars: Sometime in the past, large ripples wandered the dusty lanes of this landscape, sandblasting the hills as they marched on by. Those ripples stopped moving and turned into the fossils you see here. Their bumpy texture indicates that they too are slowly being eroded away. (HiRISE ESP_026462_1740) read more ❯

A piece of Mars: Here is an example of an aeolian enigma. Dunes are depositional, meaning they are made of stuff that piles up on a surface. But these dunes show the strata of the underlying rock within them, which means these things were made from erosion of this rock. So we don't really know how they form, although a few ideas have been kicked around. (HiRISE PSP_008313_1730) read more ❯

A piece of Mars: Dunes near the north pole take on a stretched appearance. It's been proposed that ice in the dunes acts to cement them, which makes them look elongated. (HiRISE PSP_010219_2785) read more ❯