Following the tracks of NASA’s Curiosity rover

HOW YOU came to be on this flat desert plain at this time does not matter. What matters is the landscape around you.

To the north there is what appears to be a rim around the world, brightened by morning-lit dust at its base, darker as it rises into the sky. In some places it is a disordered, stepping-stone staircase of hummocky hills; in some it has a steep, solid face. However they are reached, though, its heights are strangely continuous and peculiarly even in stature: a scarp, not a mountain range, one that curves as it stretches to the left and right, the east and west.