American soldiers with the 173rd Airborne Brigade Battle Company, on a battalion-wide mission in the Korengal Valley, looking for caves, weapons caches and known Taliban leaders, 2007. Tanner Stichter tends to Spc. Carl Vandeberge in the bushes moments after Vandeberge was shot in the stomach during a Taliban ambush, which killed one soldier and wounded two others. (Photo by Lynsey Addario)

Jeret Cooper of Vernon, British Columbia rides the horse Einstein Quest in the novice bareback event during the Calgary Stampede rodeo in Calgary, Alberta, Canada on July 11, 2022. (Photo by Todd Korol/Reuters)

Two orphaned wallaby joeys enjoy a play date to help them boost their social skills in Australia early July 2023. The rescued joeys are being hand-raised at Aussie Ark in News South Wales. (Photo by Aussie Ark/Cover Images)

An image from House Television shows Republican John Rose speaking on the floor of the House of Representatives as his son Guy makes a face in Washington DC, US on June 4, 2024. (Photo by AP Photo)

A man walks on the Cobb as storm waves break behind on December 13, 2011 in Lyme Regis, England. (Photo by Matt Cardy/Getty Images)

Emma Watson poses at the winners boards at the Sony Ericsson Empire Film Awards at the Grosvenor House Hotel on March 9, 2008 in London England. (Photo by Dan Kitwood/Getty Images)

Skeleton involves a person riding a small sled down a frozen track while lying face down. The sport is a more intense form of luge because skeleton competitors leap onto the sled and slide downhill head first. Skeleton athletes can reach up to 80 mph on straightaways, causing forces up to 5g, so the helmet is a critical component for attitude as well as safety.

NASA's DHC-3 Otter plane flies in Operation IceBridge-Alaska surveys of mountain glaciers in Alaska in this image released on September 18, 2014. Over the past few decades, average global temperatures have been on the rise, and this warming is happening two to three times faster in the Arctic. (Photo by Chris Larsen/Reuters/NASA/University of Alaska-Fairbanks)