The crater is exposed and roughly circular, 390 meters wide, with a rim that rises as much as 53 meters above its floor. Beneath that floor lie about 23 meters of sediment, accumulated over the millions of years since the bowl was carved, gradually burying the deepest scar. What makes Aouelloul scientifically valuable is its simplicity. It is small, well-preserved, and clearly the work of a single sudden event rather than the slow grind of erosion or the upheaval of tectonics. Standing on the rim, you are looking at the frozen aftermath of a collision measured in fractions of a second, an instant of cosmic chemistry preserved in stone.

Scattered around the rim are tektites, fragments of natural glass forged in the heat of impact. When the meteorite struck, the energy released was enough to melt the local sandstone and fling molten droplets outward, where they cooled into glassy beads now called Aouelloul glass. It was the chemistry of this glass, carrying a trace of extraterrestrial material, that confirmed the crater's impact origin and ruled out a purely terrestrial explanation. Curiously, very few actual meteorite fragments have been recovered. In 1973 the Zerga meteorite turned up just outside the rim to the south-southeast, but scientists remain unsure whether it is connected to the impact at all, or simply a separate stone that happened to land nearby.

Estimates place the crater's age at 3.1 million years, give or take 300,000, putting the impact in the Pliocene epoch. That is recent by geological standards yet unimaginably distant in human terms, predating our species by millions of years. To stand here is to confront two very different clocks at once. There is the instant of the strike, faster than any human reflex, and there is the patient three-million-year drift of sand that has been filling the wound ever since. The Sahara reads as timeless and unchanging, but Aouelloul tells a different story: this is a landscape that has been struck, scarred, and is still, slowly, healing over.