A woman wears a face mask in the part of the city near neighbourhoods known for burning coal for heating in Ulaanbaatar, Mongolia January 26, 2017. Not many people in Ulaanbaatar wear masks to protect themselves against pollution. (Photo by B. Rentsendorj/Reuters)

Undated handout photo issued by Carhenge Glastobury of the Carhenge installation by artist Joe Rush, on the site of Glastonbury Festival at Worthy Farm in Somerset. Made of 24 vintage cars erected in the centre of the festival, the installation emulates the ancient stone structure at Stonehenge. Issue date: Tuesday, June 20, 2023. (Photo by Matt Cardy/PA Wire Press Association)

Students pose for a pictures taken by their friends during spring break on the beach in the resort city of Cancun, Mexico, February 27, 2009. (Photo by Israel Leal/AP Photo)

“I think as mothers we are all just trying our best”. – Gisele Bundchen. (Photo by Mads Nissen/AFP Photo)

People run away as a building is toppled during a controlled demolition as part of an urban transformation in Ankara, Turkey, February 3, 2014. (Photo by Serap Doganyigit/Reuters)

Bride Yulia Tagil sits on the backseat of a bike as she arrives for her alternative wedding ceremony on a square in Tel Aviv July 25, 2010. The alternative wedding ceremony was intended to demonstrate against the current situation in Israel, where the only way for Jews to get married by law is through the Chief Rabbinate. (Photo by Nir Elias/Reuters)

In this November 28, 1966 file photo, one of the 10 beagles involved in the first test of the Veterans Administration Hospital in East Orange, N.J. smokes a cigarette through a machine linked to its windpipe by a plastic tube to test any link between smoking and emphysema. (Photo by AP Photo)

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.