Engine driver Josef Kowatsch (top L) steers a train through the NEAT Gotthard Base Tunnel during a media visit near the town of Erstfeld August 24, 2015. Crossing the Alps, the world's longest train tunnel should become operational at the end of 2016, consisting of two parallel single track tunnels, each of a length of 57 km (35 miles). (Photo by Arnd Wiegmann/Reuters)

A small section of the expanding remains of the Veil Nebula, a massive star that exploded about 8,000 years ago. The entire nebula is 110 light-years across, covering six full moons on the sky as seen from Earth, and resides about 2,100 light-years away in the constellation Cygnus, the Swan. Image taken by NASA's Hubble Space Telescope. Released September 24, 2015. (Photo by Reuters/NASA/ESA/Hubble Heritage Team)

A couple hugs while standing near a Christmas tree made out of plastic bins and plastic hampers outside the Museum of History in Monterrey, Mexico, December 4, 2015. The humble Christmas tree has a rich history, from evergreen trees used to symbolise eternal life in Ancient Egypt to tree worship among pagan Europeans. The modern version has its origins in Germany, where the song “O Tannenbaum” is still a festive favourite. Today the traditional tree with lights and decorations appears in cities including Washington, Moscow and Beirut. Alternative constructions range from recycled rubbish in Mexico City to old window frames in Rakvere, Estonia. Whatever the shape or size, the message is the same: Merry Christmas. (Photo by Neil Hall/Reuters)

Pakistani boys jump in the water to cool off in a pond to beat the heat wave continues in Larkana, Pakistan, 26 June 2021. Pakistan's Meteorological Department (PMD) said the weather in the city will remain hot and humid for the next three days. (Photo by Waqar Hussain/EPA/EFE)

Model airplane enthusiasts take part in an event at a model airplane field in Mamak district of Ankara, Turkey on December 30, 2021. Model airplane enthusiasts, each owns different sizes and types of aircrafts, have the opportunity to have fun while training. Weekend meetups also give them an opportunity to help each other on technical issues. (Photo by Dogukan Keskinkilic/Anadolu Agency via Getty Images)

Santiago Eneme (second left) and his Equatorial Guinea teammates can’t watch during their last 16 penalty shoot-out with Mali, although they did go on to win at Limbe Omnisport Stadium in Limbe, Cameroon on January 26, 2022. (Photo by Thaier Al-Sudani/Reuters)

A pro-Palestinian demonstrator reacts as she is escorted by security personnel after scuffling with an observer, as protesters in support of Palestinians in Gaza and pro-Israel counter-protesters gather at the encampment on the campus of the University of California Los Angeles (UCLA), amid the ongoing conflict between Israel and the Palestinian Islamist group Hamas, in Los Angeles, California, U.S. April 29, 2024. (Photo by David Swanson/Reuters)

Zhao Deli waves as he pilots his self-made “flying scooter” in Dongguan, Guangdong Province, China, 12 August 2018 (issued 16 August 2018). Inspired by a cartoon he watched as a child, Zhao Deli sold off his apartment in pursuit of his dream of building a flying scooter. (Photo by Aleksandar Plavevski/EPA/EFE)