A protester gestures as he holds a dog before a burning barricade during protests in Harare, Zimbabwe on January 15, 2019. (Photo by Philimon Bulawayo/Reuters)

A hiker walks in the Zillertal Alps during an autumn day near the village of Ginzling, Austria, October 15, 2019. (Photo by Lisi Niesner/Reuters)

A worker carries a basket of fish, at a wholesale fish market, on the outskirts of Kolkata, March 15, 2017. (Photo by Rupak De Chowdhuri/Reuters)

Bull riders prepare prior to a bull riding event in Santa Tecla, El Salvador, December 15, 2016. (Photo by Jose Cabezas/Reuters)

A woman touches a robot at the 2018 World Robot Conference in Beijing on August 15, 2018. The conference will be held from 15 to 19 August and will include a conference on robotics, an exhibition and a robot competition with the participation of robotics enterprises to showcase their robot products. (Photo by Wang Zhao/AFP Photo)

A resident looks at a parade marking the 496th anniversary of Panama City, Panama August 15, 2015. Modern-day Panama City includes the historical ruins of the original Panama Viejo settlement founded on August 15, 1519 by Spaniard Pedro Arias Davila, according to local media. (Photo by Carlos Jasso/Reuters)

An artist performs with a lion during the presentation of the new international show “Extreme arena” at the Ukrainian National Circus in Kiev, Ukraine, 15 September 2016. The show will be staged from 15 September to 11 December 2016. (Photo by Roman Pilipey/EPA)

Two F-15E Strike Eagles wait to receive fuel from a KC-135R Stratotanker during exercise Red Flag 15-1 on their way to Nellis Air Force Base, Nev., Jauary 23, 2015. The F-15s are assigned to the 4th Fighter Wing. U.S. (Photo by Airman 1st Class Aaron J. Jenne/Reuters)