Space is full of spectacular geological structures: here are five of them

When we talk about amazing geological features, we often limit ourselves to those on Earth. But as a geologist, I think that’s crazy – there are so many structures on other worlds that can excite and inspire, and that can put processes on our own planet into perspective.

Here, in no particular order, are the five geological structures in the solar system (excluding Earth) that most impress me.

The grandest canyon

I left out the solar system’s biggest volcano, Olympus Mons on Mars, so I could include that planet’s most spectacular canyon, Valles Marineris. Being 3,000km long, hundreds of kilometers wide, and up to eight kilometers deep, this is best seen from space. If you were lucky enough to stand on one rim, the opposite rim would be way beyond the horizon.