Mars

The camera is the rover, which is the thing to hold on to while you look around. Turn one way and most of the frame is machine: a deck of solar panels gone pink with settled dust, the camera mast rising directly overhead, the high-gain antenna, cabling and instrument housings, all of it sitting a couple of feet off the ground. Turn the other way and there is nothing at all - a plain so flat that the horizon is a clean line, pale rusty soil with a scatter of darker gravel, and the wheel tracks running back from under the deck in two parallel bands until they get too faint to follow. In places the ruts are deep enough to have thrown up ridges. The sky is not blue and not black; suspended dust makes it a pale butterscotch that goes slightly greener towards the horizon, and there is no sharp shadow anywhere because the whole sky is the light source.

This is not Earth. The surface here is Meridiani Planum, a flat plain near the Martian equator, photographed by the Opportunity rover after it landed in January 2004.

The mission was designed to last ninety Martian days. It ran for more than five thousand, covering forty-five kilometres - further than any vehicle has driven on another planet. The last transmission came in June 2018, when a dust storm covered the sky and the solar panels stopped charging.

The site was chosen because orbiters had detected haematite, a mineral that on Earth usually forms in standing water. Opportunity found it, and found the layered rock to go with it.