Category: HiRISE images

These are blog posts showing my daily image of Mars, which is usually a small piece of a HiRISE image. It includes some text describing the image, and it was also posted on Twitter, Facebook, and Pinterest.

Wind and maybe water too

A Piece of Mars: Along the right side of this 0.5x0.5 km (0.31x0.31 mi) scene is the rim of a crater - the stripes are layers exposed (and then perhaps draped by falling ejecta) as the crater formed. To the ...

Exhumed dunes!

A Piece of Mars: The large dunes in the middle of this 375x450 m (0.23x0.28 mi) scene run along a valley (the small dunes at top and bottom are on high ground). What's amazing about this is that the ends ...

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 ...

Cross-strata or not?

A Piece of Mars: Sand dunes are one of the few sedimentary phenomena that leave behind layers that aren't horizontal. They tend to have a characteristic lean to them (and we call them cross-strata). So when I see something that ...

Westward moving

A Piece of Mars: No great scientific insights today, just a really lovely view of bright TARs and some very dark sand in this 0.875x0.5 km (0.54x0.31 mi) scene. Only one major wind acts in this region, moving sediment toward ...

Experimenting with 3D views

A Piece of Mars: I often use JMARS to visualize Mars data sets, especially images. They've recently updated their 3D layer, allowing folks to make lovely vistas by overlaying DTMs with images. I'm new at this, but I'll experiment and ...

Reversing slip faces

A Piece of Mars: This 523x750 m (0.32x0.47 mi) scene shows a large dune. It's quite colorful for some reason, although it's partially false-color. What caught my eye is that the slip face on this dune has reversed direction, which ...

The real tetrahedrons of Mars

A Piece of Mars: The real tetrahedrons of Mars are dunes, built by winds blowing sand from more than one direction. This 0.5x0.5 km (0.31x0.31 mi) area shows a dune formed from two winds that are about 90 degrees apart: ...

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 ...

Sand tails

A Piece of Mars: Up on the tallest volcanoes, the wind screams downhill at night. This 500x500m (0.31x0.31 mi) scene shows how dust is carried downhill, but only that which is trapped behind boulders and crater rims sticks around. The ...