Starlings come home to roost on Brighton's Old Pier as the sun sets on December 21, 2011 in Brighton, England. December 21 marks the winter solstice, the shortest day of the year. (Photo by Dan Kitwood/Getty Images)

Sophia Weisberg of Brazil competes on the balance beam during the 53rd Artistic Gymnastics World Championships in Jakarta, Indonesia, October 21, 2025. (Photo by Dita Alangkara/AP Photo)

An air tanker flies low over a wildfire burning on the edge of the Cariboo region city of Williams Lake, British Columbia, Canada on July 21, 2024. (Photo by Spencer Stratton/Handout via Reuters)

The NASA Extreme Environment Mission Operations (NEEMO) 21 mission began on July 21 as an international crew of aquanauts splashed down to the undersea Aquarius Reef Base, located 62 feet below the surface of the Atlantic Ocean in the Florida Keys National Marine Sanctuary. The NEEMO 21 crew will perform research both inside and outside the habitat during a 16-day simulated space mission. During simulated spacewalks carried out underwater, they will evaluate tools and mission operation techniques that could be used in future space missions, including journeys to Mars. (Photo by Karl Shreeves/NASA)

Belarusians wearing national costumes celebrate a Pull the Kolyada Up the Oak rite in the village of Martsiyanauka, some 77 km (48 miles) east of capital Minsk, Belarus, Thursday, January 21, 2016. The merry ancient rite Pull the Kolyada Up the Oak marks the end of Orthodox Christmas celebrations in Belarus. On Jan. 21 a wheel, the so-called Kolyada, would be pulled up an oak or any old tree. The Belarusians believed that the ritual heralds a good harvest, luck and happiness for the entire year. (Photo by Sergei Grits/AP Photo)

Hundreds of amazonian models strutted the streets of New York in order to be given a chance to make it big in the lingerie brand as they returned for the first set of call backs. Here: Model Diane Mello attends the 2016 Victoria's Secret Fashion Show castings on October 21, 2016 in New York City. (Photo by Michael Stewart/Getty Images)

A tea garden worker plucks tea leaves inside Aideobarie Tea Estate in Jorhat in Assam, India, April 21, 2015. Unrest is brewing among Assam's so-called Tea Tribes as changing weather patterns upset the economics of the industry. Scientists say climate change is to blame for uneven rainfall that is cutting yields and lifting costs for tea firms. (Photo by Ahmad Masood/Reuters)

Romanian soldiers take part in a joint military exercise with NATO members, called “Agile Spirit 2015” at the Vaziani military base outside Tbilisi, Georgia, July 21, 2015. Georgian soldiers along with U.S. marines and platoon-size units from Bulgaria, Latvia, Lithuania and Romania are taking part in the exercises at the Vaziani military base outside Tbilisi. (Photo by David Mdzinarishvili/Reuters)