Mariusz Potocki (center with orange goggles) and the National Geographic and Rolex Perpetual Planet Everest Expedition team collect the highest ever recorded ice core sample at the South Col Glacier. Credit: Dirk Collins, National Geographic and Rolex Perpetual Planet Everest Expedition. There isn’t much room for error 8,000 meters above sea level, and everyone on the expedition knew it. Mount Everest is notoriously challenging to climb, but conducting research on the iconic mountain is an even taller task. It was clear and sunny, but the thin air was bitterly cold. The team relied on supplemental oxygen to breathe. Bundled in brightly colored snowsuits with their faces obscured by ski goggles, the scientists were virtually unrecognizable. They wrote their names on their chests with Sharpies.