When a researcher picks up an object — whether it’s a scrap of leather from a dig site, a fossil from a museum drawer or a newly fallen meteorite — their first question might be, “What is this thing?” ...

Despite seeming like a relatively stable place, the Earth's surface has changed dramatically over the past 4.6 billion years. Mountains have been built and eroded, continents and oceans have moved ...

Radiometric dating, utilizing the predictable decay rates of radioactive isotopes within rocks and other materials, is the primary method for determining the age of geological samples. Multiple ...