In this photo posted on Twitter, Sunday, May 3, 2015, and provided by NASA, Italian astronaut Samantha Cristoforetti sips espresso from a cup designed for use in zero-gravity, on the International Space Station. Cristoforetti, the first Italian woman in space, fired up the first espresso machine in space, which uses small capsules, or pods, of espresso coffee. (Photo by AP Photo/NASA)

In this November 2, 2017 photo, Mathew Fulkerson and his wife Leigh Ann pose at their Subterra Airbnb located in a former underground missile silo base near Eskridge, Kan. It was designed to house a nuclear warhead six decades ago – but now, this Cold War silo is the perfect spot for a mini break at just $133 a night. (Photo by Thad Allton/The Topeka Capital-Journal via AP Photo)

Farmers clash with riot policemen during a protest outside the Greek Agriculture Ministry on March 8, 2017 in Athens, Greece. Two people were detained after the windows of two police vans were smashed as approximately 1,000 farmers, mainly from the island of Crete, took part in the protest. (Photo by Nikolas Georgiou/ZUMA Wire/Rex Features/Shutterstock)

In this March 22, 1975 file photo, a refugee clutches a baby as a government helicopter gunship carries them away near Tuy Hoa, Vietnam, 235 miles northeast of Saigon. They were among thousands fleeing from Communist advances. AP Photographer Nick Ut will be retiring from the AP in March 2017 after 51 years of taking photographs from the front lines of the Vietnam War to the red carpets of Hollywood. (Photo by Nick Ut/AP Photo)

Mount Etna, Europe's most active volcano, is seen from the side of a road as it spews lava during an eruption in the early hours of Thursday, March 16, 2017. Sicily's Mount Etna volcano unleashed an explosion Thursday, hurling molten rocks and steam that rained down on tourists, journalists and a scientist who scrambled to escape the barrage. Ten people were reported injured. (Photo by Salvatore Allegra/AP Photo)

Vietnam’s Son Doong cave, the largest in the world, could hold a 40-story skyscraper inside. The pristine ecosystem has its own river and jungle. Despite its size, Son Doong wasn’t discovered until 1991. It was lost again for nearly two decades and was fully explored for the first time in 2009. (Photo by Jason Speth/HuffPost)

In this Sunday, March 11, 2017 photo, children fight in a boxing ring in Chitungwiza, Zimbabwe. Zimbabwean boys as young as 10 hurry every weekend to a boxing ring whose nickname, Wafa Wafa, in the local Shona language suggests that whoever enters will be lucky to come out alive. (Photo by Tsvangirayi Mukwazhi/AP Photo)

A seller dressed as Snegurochka (The Snow Maiden) shows Christmas toys at the Christmas decorations set in the Moscow GUM State Department store in Moscow, Russia in Moscow, Russia, Monday, December 16, 2019. (Photo by Pavel Golovkin/AP Photo)