Feature Types

A bowl-shaped depression blasted out when an asteroid or comet strikes a solid surface. Craters are the most common landform in the Solar System, and their density is used to date surfaces — the more craters, the older the terrain.

An enormous impact structure, hundreds to thousands of kilometres across, formed by a giant early impact — often multi-ringed and later flooded by lava, as with the lunar maria.

A broad, gently-sloping volcano built by fluid lava flows. On Mars, low gravity and a stationary crust let shield volcanoes grow to enormous size — Olympus Mons is the tallest in the Solar System.

An 'ice volcano' that erupts water, ammonia, or methane instead of molten rock, resurfacing the frozen worlds of the outer Solar System — from Ceres's Ahuna Mons to the plumes of Enceladus.

A broad, dark plain of solidified lava. The lunar maria — the 'seas' — are vast basalt flows that filled ancient impact basins; similar plains cover much of Venus and Mars.

The ancient, heavily-cratered high terrain of a world, older and more rugged than the smooth plains — like the bright lunar highlands or the tessera terrain of Venus.

A deep, steep-sided valley cut by tectonics or water. Mars's Valles Marineris is a canyon system so large it would stretch across the entire United States.

A cliff formed where the crust has broken and one side has risen relative to the other. Mercury is covered in long lobate scarps produced as the planet cooled and shrank.

A chain or massif of mountains, whether uplifted by tectonics, thrown up around an impact basin, or built by volcanism — from Venus's Maxwell Montes to the water-ice mountains of Pluto.

Complex, intensely deformed 'tile' terrain unique to Venus — the planet's oldest and most tectonically tortured surface, ridged and grooved in intersecting directions.

A large circular volcanic-tectonic feature, ringed by fractures, thought to form where hot material rises and pushes up the crust — a signature landform of Venus.

Bright bands of parallel ridges and grooves that cut across the dark, ancient surface of Ganymede — young, tectonically-resurfaced ice.

A field of wind-blown dunes, showing that a world has an atmosphere and mobile sediment — from the basaltic-sand dunes of Mars to the hydrocarbon-sand dunes of Titan.

A giant channel carved by catastrophic floods of water in the distant past, evidence that liquid water once flowed across the surface of Mars.

A fan of sediment deposited where an ancient river entered a standing body of water — a prime target in the search for past life, as at Jezero crater on Mars.

A broad plain or flowing sheet of ice. On Pluto, the nitrogen-ice glaciers of Sputnik Planitia churn and flow; on Mars and the icy moons, water ice shapes the surface.

A jumble of broken, tilted blocks of crust, often where a surface has been disrupted from below — as on Europa, where it may mark places the ice shell interacts with the ocean beneath.

A lake or sea of liquid methane and ethane — found only on Titan, the one other world in the Solar System with stable liquid on its surface.