Mars Got Itself Some FLOWING SAND DUNES. Picnic Time, IMO.

Now, those sand dunes on Mars aren’t actually flowing like liquid. You’re looking at me incredulously. They aren’t. Believe me. However, I’m not going to fault you for thinking they are.

NASA:

When does Mars act like a liquid? Although liquids freeze and evaporate quickly into the thin atmosphere of Mars, persistent winds may make large  sand dunes appear  to flow and even drip like a liquid. Visible on the  above image  right are two flat top mesas in southern Mars when the  season was changing  from Spring to Summer. A light dome topped hill is also visible on the far left of  the image. As winds blow from right to left, flowing sand on and around the hills leaves  picturesque streaks. The dark arc-shaped  droplets  of fine sand are called  barchans, and are the interplanetary cousins of similar Earth-based sand forms.  Barchans  can move intact a  downwind  and can even appear to pass through each other. When seasons change,  winds on Mars  can kick up dust and are  monitored  to see if they  escalate  into another of Mars’ famous planet-scale  sand storms.

Yeah, like i said. Don’t blame yourself. They’re just  barchans.