The Villarrica Volcano is seen at night from Pucon town, Chile, July 12, 2015. Villarrica, located near the popular tourist resort of Pucon, is among the most active volcanoes in South America. (Photo by Cristobal Saavedra/Reuters)

Local residents fight to collect free drinking water from municipal corporation tanker on a hot summer day on the outskirts of Ahmedabad, India June 1, 2016. (Photo by Amit Dave/Reuters)

F/A-18 fighter jet takes off from the USS Harry S. Truman aircraft carrier in the eastern Mediterranean Sea June 13, 2016. (Photo by Baz Ratner/Reuters)

Commuters use a plastic sheet to take shelter from rain as they ride through a waterlogged road in Ahmedabad, India, July 27, 2016. (Photo by Amit Dave/Reuters)

A Palestinian female masked militant from the Al-Quds Brigades, the military wing of the Islamic Jihad, takes part in an Islamic Jihad rally in Rafah, southern Gaza Strip, 29 July 2016. (Photo by Mohammed Saber/EPA)

Bavarian herdsmen and a herdswoman in traditional dresses drive their beasts on a road during the return of the cattle from the summer pastures in the mountains near Oberstaufen, Germany, Friday, September 9, 2016. (Photo by Matthias Schrader/AP Photo)

Students from St Andrews University indulge in a tradition of covering themselves with foam to honour the “academic family” on the lower college lawn on October 23, 2017, in St Andrews, Scotland. (Photo by Jeff J. Mitchell/Getty Images)

U.S. President Donald Trump boards Air Force One to depart for Vietnam from Beijing Airport in Beijing, China on November 10, 2017. (Photo by Jonathan Ernst/Reuters)