What’s in an isotope? Quite a lot, as it turns out. A new technique developed by researchers at the Lamont-Doherty Earth Observatory now allows scientists to use an isotope of manganese not abundant on Earth to understand the record of millions of years of changes to the Earth’s surface. According to the study's lead scientists, the new technique relies on measuring extremely small amounts of the nuclide that accumulates as cosmic rays strike exposed rock surfaces over long periods of time. This will allow scientists to track processes such as erosion and glaciation that shaped the landscape over millions of years.