Mars Is Covered in a Pattern You’ve Seen in a Dried Puddle
Curiosity climbed a valley on Mount Sharp in June, got high enough to look around, and found honeycomb running to the horizon.
They’re polygonal fractures, four to eight centimeters across. Palm-sized patches. The rover has hit some smaller patches before, but never a field like this.
It looks familiar because it is. Mud dries, shrinks and cracks into polygons in a driveway puddle or across the floor of Death Valley.
Curiosity has found Martian polygons before that were old mud cracks. Freeze and thaw cycles do it too, and so does burial, when the sediment above squeezes water out of the layer below. The team is still working out which one made these.
All of the candidates involve water.
Curiosity has been up there fourteen years, twelve of them climbing a mountain whose lower slopes once held lakes and streams. It’s already shown that ancient Mars had the water, chemistry and nutrients for microbial life, and it’s found organic molecules that are precursors to RNA and DNA.
Nobody yet knows whether biology or geology made them.
And now a plain of dried cracks, hand-sized, running past the horizon on a planet that dried out billions of years ago.
Images by NASA/JPL-Caltech/MSSS.
