Mysterious purple coating found on Mars rocks
The color pops up almost everywhere the Perseverance rover has looked—and could hold clues to the planet’s potential for ancient life.
Red dust paints Mars in ruddy hues, from the surface to the skies. But NASA's Perseverance rover has spotted swaths of another color among the rusty shades. At nearly every site the robotic geologist visits, the Martian palette includes purple.
The color forms a thin, smooth coating on some stones, and it leaves paint-like blobs on others. Still other rocks look as if they've been partially frosted in magenta icing, says Ann Ollila, a geochemist at Los Alamos National Laboratory who presented an early analysis of the coatings at a recent conference of the American Geophysical Union (AGU).
The color touches rocks of all different shapes and sizes—even tiny pebbles haven't escaped the pops of purple. But how,