A Crater in Western Australia Looks Like a Spider Because the Ground Rebounded

In Western Australia's Kimberley region sits a geologic feature NASA calls aptly named: Spider Crater. It is the product of a meteorite impact followed by hundreds of millions of years of erosion, which is why the structure sprawls across the landscape instead of sitting in a tidy bowl.

Geologists believe the arachnoid, leg-like pattern at its middle is the remnant of a central uplift — the raised portion of the crater floor that formed in the rebound of the initial impact shock. That is the counterintuitive part of crater formation: after the shock passes, the ground does not simply stay dented. The floor lifts back up, and hundreds of millions of years of erosion then sculpt what remains of that raised core.