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.

Physicist Arie van't Riet uses a series of duel X-ray cameras to capture flowers, plants and small animals in living dioramas. The x-rays are then finished and colorized in Photoshop. Giving way to some breathtaking nature scenes. Photo: “Chameleon and Begonia”. (Photo by Arie van't Riet)

Karsten Thielker, a Pulitzer Prize-winning German photographer with The Associated Press who covered human suffering in conflict zones around the globe, has died at the age of 54. Thielker died on October 3 in Berlin of esophageal cancer, his wife Janna Ressel said. Here: A wounded Russian soldier, who has been evacuated with his comrades, weeps in a helicopter on his way out of Grozny on Friday, February 3, 1995, as the fighting in the Chechen capital continues. The massive Russian force that invaded Chechnya has taken very heavy losses against a small but determined guerrilla force. (Photo by Karsten Thielker/AP Photo/File)

A helicopter flies close to a volcanic eruption which has begun in Fagradalsfjall near the capital Reykjavik on March 20, 2021 in Fagradalsfjall, Iceland. On Friday the Icelandic meteorological office announced a volcano, referring to a mountain located south-west of the Capital Reykjavik has erupted after thousands of small earthquakes in the area over the recent weeks. A no-fly zone has been established in the area. (Photo by Vilhelm Gunnarsson/Getty Images)

A woman is dragged away by Chinese men moments after she was seen talking to journalists near the site of a reported explosion outside the U.S. Embassy in Beijing, China, Thursday, July 26, 2018. A man exploded a small homemade bomb outside the U.S. Embassy in Beijing on Thursday, injuring only himself, according to police and an embassy spokesperson. (Photo by Ng Han Guan/AP Photo)

In this July 11, 2018 photo, members of a private photo studio take pictures of a woman in Havana, Cuba. New rules for private business indicate that the government has ruled out going further to open private business, such as allowing small and medium enterprises and authorizing business to operate as societies. Currently, private business licenses are granted only to individuals, and only one license per person. (Photo by Desmond Boylan/AP Photo)

Young people jump over a bonfire as they take part in the Ivan Kupala Night celebration, a traditional Slavic holiday, outside the small town of Turov, some 270 km south of Minsk, on July 6, 2016. People celebrate Kupala Night with bonfires that last throughout the night with some leaping over the flames as it is believed that the act of jumping over the bonfire cleanses people of illness and bad luck. (Photo by Sergei Gapon/AFP Photo)

Chileans watch the sky with special suits prior to a total solar eclipse on July 2, 2019 in Paiguano, Chile. Around 25,0000 tourists arrived to Paiguano, a small town of around 1,000 inhabitants in the Elqui Valley, 650 km away Santiago. This is the only Earth's total solar eclipse of 2019 and the first one since 2017. From this point, the sun will fully disappear for around two minutes. It is best visible from a stripe in the South Pacific, Chile and Argentina. (Photo by Marcelo Hernandez/Getty Images)