Tag Archives: polar

Mars’ giant bubble wrap

A Piece of Mars: This 0.7x0.5 km (0.43x.31 mi) scene shows Mars' giant yellow bubble wrap, with each "bubble" about 100 m across (seriously, don't you want to pop them?). These are actually a type of dune called a "dome ...

Dunes fighting for survival

A Piece of Mars: Having a bad day? You're in good company with these dunes in this 0.96x0.48 km (0.6x0.3 mi) scene. The gray barchanoid dunes are covered in ripples, as the wind valiantly tries to push the sand to ...

Where on Mars is this dune?

A Piece of Mars: This 0.48x0.27 km (0.3x0.17 mi) scene shows a rotund barchan dune. Can you tell from looking at it where on Mars it might be? To me the most obvious feature are the bumpy piles at the ...

Shades and textures

A Piece of Mars: This 480x270 m (0.3x0.17 mi) scene shows the contact between two very different terrains. On the left is a bright surface with polygonal cracks (characteristic of periglacial terrain - this is at a high latitude). On ...

Eroded dune

A Piece of Mars: Barchan dunes on Mars have a characteristic crescent shape, with a steep slope ("slip face") on the inside of the sharpest curve (see examples like this, this, these, or this). This image (873x491 m, or 0.54x0.31 ...

Springtime for sand dunes and polar ice

A Piece of Mars: This 480x270 m (0.3x0.17 mi) scene shows a dark dune peeking out from under its cover of winter frost. In this picture it's late spring, but still cold up at this latitude - it's as far ...

Dune trails

A Piece of Mars: The dark dunes in this 0.96x0.54 km (0.60x0.34 mi) scene are slowly migrating towards the lower left. Look closer and you'll see brighter ripples between the dunes - the biggest ones are ~8m (26 ft) apart. ...

Frosty dunes

A piece of Mars: In this image (0.96x0.54 km or 0.6x0.33 mi), it's late winter and the sun is barely above the horizon here near the north pole. The dunes are covered in winter frost, most of which is CO2 ...

Melty dunes

A Piece of Mars: With all due apologies to followers of the show Coupling, I have to call these things "melty dunes". This link shows what a crisp dune should look like. The dunes in this 600x450 m (0.37x0.28 mi) ...

The bright barchan

A piece of Mars: Most dunes on Mars are dark, like these and these. So why is this one bright? It's adjacent to a more typical, dark dune. It's possible that there are two populations of sand here that are ...