Ever been late because you misread a clock? Sometimes, the “clocks” geologists use to date events can also be misread. Unravelling Earth’s 4.5-billion-year history with rocks is tricky business. < <Case in point: the discovery of an ancient meteorite impact crater was recently reported in the remote Pilbara region of Western Australia. The original study, by a different group, made headlines with the claim the crater formed 3.5 billion years ago. If true, it would be Earth’s oldest by far.

As it turns out, we’d also been investigating the same site. Our results are published in Science Advances today. While we agree that this is the site of an ancient meteorit