The crater was found in 1921 by an Aboriginal stockman named Billy Seward, working the Dalgaranga pastoral station. He led the station manager, Gerard Wellard, to the spot, and Wellard soon turned up the strange dark fragments scattered around it. It took until 1923 for samples to reach the Western Australian Museum, and the site went unmentioned in scientific literature until 1938. For decades the recognition of one of the country's most unusual craters rested on the local knowledge of a man whose name might easily have been lost. That he is remembered at all, when so many such finders are not, is worth pausing on.

What makes Dalgaranga extraordinary is what hit it. The fragments around the rim are mesosiderite, a rare stony-iron meteorite that mixes silicate rock and metal in roughly equal measure, the wreckage of a violent collision between two very different bodies somewhere in the early solar system. Mesosiderites are uncommon enough as museum specimens. As crater-makers they are unique: Dalgaranga is the only impact crater on Earth known to have been formed by one. The asymmetry of the bowl and its scattered debris tells investigators the projectile came in on a shallow angle, streaking down from the south-southeast before it struck.

The crater is geologically fresh, which is exactly why it survives. Across most of the world a dent this shallow would have been erased by weather and time within a few thousand years. Here it persists, the meteorite fragments still lying where they fell rather than rusted away to nothing. Estimates of its age range widely, from as recent as 3,000 years to a few hundred thousand, depending on the method. It was blasted into some of the oldest rock on Earth: weathered Archaean granite of the Yilgarn craton, crust that was already billions of years old when the meteorite arrived. A momentary scar on an almost timeless surface.

Dalgaranga's claim to being Australia's tiniest impact crater comes with one careful caveat: a handful of the smallest pits in the Northern Territory's Henbury crater field are smaller still. But Henbury was made by an ordinary iron meteorite that broke apart and gouged a whole cluster of holes, the common story of how small craters form. Dalgaranga stands alone, a single strike by a single rare object. The flat, ancient, slow-eroding surface of the Murchison is exactly the kind of place where such a fragile record can survive across millennia, which is partly why Western Australia holds so many of the continent's recognised impact sites. Most of the planet would have swallowed a 24-metre dent long ago. Out here, it waits.

Why does a 24-metre hole matter to science? Because small, fresh, well-preserved craters are rare laboratories. Most impacts of this scale are quickly buried or eroded, so the ones that endure let researchers study how a low-angle strike throws out its ejecta and shapes the ground, with the actual meteorite still present to identify. Dalgaranga has been mapped, sampled, and revisited for exactly that reason. For the visitor who makes the long drive out, there is not much to see at first glance, just a quiet depression in the scrub. But knowing what it is changes the looking. Somewhere overhead, the object that made it once fell out of the sky.