The red planet's red looks different to a robot with hyperspectral cameras for eyes. //

Those colors are a geological infographic. They represent time, laid down in layers, stratum after stratum, epoch after epoch. And they represent chemistry. NASA scientists pointing cameras at them—the right kind of cameras—will be able to tell what minerals they’re looking at and maybe whether wee Martian beasties once called those sediments home. “If there are sedimentary rocks on Mars that preserve evidence of any ancient biosphere, this is where we’re going to find them,” says Jim Bell, a planetary scientist at Arizona State University and the principal investigator on one of the rover’s sets of eyes. “This is where they should be.” //

That’s what they’re looking for. But that’s not what they’ll see. Because some of the most interesting colors in that real-life, 50-meter infographic are invisible. At least they would be to you and me, on Earth. Colors are what happens when light bounces off or around or through something and then hits an eye. But the light on Mars is a little different than the light on Earth. And Perseverance’s eyes can see light we humans can’t—light made of reflected X-rays or infrared or ultraviolet. The physics are the same; the perception isn’t.