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.

American model Emily Ratajkowski shows off her new swimwear line in the second decade of March 2022. (Photo by emrata/Instagram)

Aerial acrobat Schindler, notorious for his foolhardy stunts, practising one of his tricks listing out of the vertical, from a Klemp plane piloted by Richard Perlia. (Photo by General Photographic Agency/Getty Images). Circa 1927

The Royal Observatory just announced its Astronomy Photographer Of The Year 2013 winners. Australian photographer Mark Gee was chosen among a thousand amateur and professional photographers around the globe to win the top title. His work is part of an exhibition of the winning photographers, which opened on Sept. 19 at the Royal Observatory Greenwich. The Royal Observatory shared with us the winners and notable mentions of the competition. Their descriptions of the prizewinners can be found below the images.

Worker Shi Shenwei pulls a wheelbarrow at the construction site of a Buddhist temple in the village of Huangshan, near Quanzhou, Fujian Province, China, September 28, 2016. For most construction workers, lunch is a welcome break to rest and refuel. Not for Shi Shenwei. the 23-year-old spends his midday break jumping and swinging through a maze of scaffolding poles, performing a fitness routine that has made him China's latest social media sensation. (Photo by Thomas Peter/Reuters)

A woman argues with police officer during a protest in support of jailed opposition leader Alexei Navalny in Ulan-Ude, the regional capital of Buryatia, a region near the Russia-Mongolia border, Russia, Wednesday, April 21, 2021. Navalny's team has called for nationwide protests on Wednesday following reports that the politician's health was deteriorating in prison, where he has been on hunger strike since March 31. Russian authorities have stressed that the demonstrations were not authorized and warned against participating in them. (Photo by Anna Ogorodnik/AP Photo)