Mount Sinabung, a highly active volcano on Sumatra island, erupted several times this week. A volcanology agency has declared a danger zone of about four miles from the crater after seven farmers were killed and two others seriously injured. Here: A man carries his dog as a giant ash cloud rises from the Sinabung volcano in Karo, Indonesia on May 26, 2016. (Photo by Sutanta Aditya/Barcroft Images)

Zhang Ze of China in action during his Oceania zone group1 match against Bernard Tomic of Australia of the 2011 Davis Cup on July 8, 2011 in Beijing, China. (Photo by Lintao Zhang/Getty Images)

A trader weighs tobacco at a market in el-Fasher, in North Darfur February 5, 2015. Tobacco is one of the North Darfur war zone's main cash crops. (Photo by Mohamed Nureldin Abdallah/Reuters)

Completion is near on Monaco's tallest skyscraper ever, and its first new one since the 1980s. Fueled by a luxury-housing boom in the tax-haven nation, the Odeon Tower's so-called Sky Penthouse is expected to sell for more than any other apartment in the world has ever sold before. Photo: The five-story Sky Penthouse is expected to be complete in September 2015. The water slide extends from a dance floor in the residence down to a private infinity pool. (Photo by Tour Odeon)

Migrants rush as they try to get on a train heading to the border with Serbia at the train station of Gevgelija, on the Macedonian-Greek border, on August 9, 2015. Non-EU Serbia's frontier with Hungary, which is in the bloc's passport-free Schengen zone, has become a major crossing point for the huge numbers of migrants entering the EU. (Photo by Dimitar Dilkoff/AFP Photo)

Armenian police officers detain a protestor during an opposition rally in the Freedom Square in Yerevan, Armenia, 12 November 2020. Protesters demanded the resignation of Armenian Prime Minister Nikol Pashinyan and his government. The unrest and protest erupted in Yerevan on 10 November 2020 after Armenian Prime Minister and Presidents of Azerbaijan and Russia signed a trilateral statement announcing the halt of ceasefire and all military operations in the Nagorno-Karabakh conflict zone. (Photo by Stepan Poghosyan/EPA/EFE)

A man reacts after catching a trout with his hands during an event promoting the Ice Festival on a frozen river in Hwacheon, about 20 km (12 miles) south of the demilitarized zone separating the two Koreas, January 10, 2015. The annual ice festival, which is one of the most famous and biggest festivals in South Korea, expects to see more than 1,000,000 people attend. The festival lasts for three weeks from January 10 this year. (Photo by Kim Hong-Ji/Reuters)

A visitor jumps for a photograph on the world's highest and longest glass-bottomed bridge above a valley in Zhangjiajie in China's Hunan Province on August 21, 2016. The bridge, which opened to the public on a trial basis on Saturday, spans 430 meters (1,410 feet) and rises about 300 meters (984 feet) above a valley in a scenic zone, making it the world's highest and longest glass-bottomed bridge according to Chinese state media. (Photo by Fred Dufour/AFP Photo)