Mars Reconnaissance Orbiter/NASA

Photograph

MarsReconnaissance Orbiter

Agency NASA

RAVAGED by the largest dust storms in the solar system and with temperatures that can fall to around -125°C, the surface of Mars is a hostile place. But what about beneath the ground – what might lurk there?

This image of an unusual crater on the slopes of Mars’s Pavonis Mons volcano was captured in 2011 by the Mars Reconnaissance Orbiter, which is still surveying the Red Planet. NASA has reposted the image on its blog to stimulate fresh discussion about the crater.

The 35-metre-wide hole at the centre of the crater …