Relentless wind

A piece of Mars: This is what the relentless work of the wind can do. That vaguely circular structure in the center of the image is probably the remains of a ~150 m diameter impact crater. Since it formed, it’s been at least partially buried in dust. That dust was probably scoured from elsewhere on the planet during many successive dust storms, and slowly accumulated on the surface here. That dust lithified and is now once again being eroded away by, you guessed it, the wind. (PSP_010345_1635, NASA/JPL/Univ. of Arizona)