Star trails form over the Memorial House of the Bulgarian Communist Party on mount Buzludzha in this long exposure picture taken on September 12, 2014. The monument was officially opened in 1981 by the Bulgarian Communist regime to mark 100 years of the set up of an organised Socialist movement, a predecessor of the Bulgarian Communist Party. The monument, no longer maintained by the Bulgarian government after the fall of the Communist regime in 1989, is now abandoned and vandalized. (Photo by Stoyan Nenov/Reuters)

Non-Hindus carry nets as they wait on the edge of the crater to catch offerings cast down by Hindus during the Kasodo ceremony at Mount Bromo, Probolinggo, Indonesia, August 12, 2014. The Kasodo ceremony is a way of Tengger Hindus to express their gratitude to God for good harvest and fortune. The offerings range from vegetables to chickens, from fruits to goats, from money to other valuables. (Photo by Fully Handoko/EPA)

A biker poses on his Bousouzoku motorbike at the Dangouzaka rest stop in Yamanashi, west of Tokyo, Japan, January 3, 2016. Police on Sunday halted a group of about two dozen Bousouzoku bikers who paraded their noisy motorcycles during an annual New Year outing in the Mount Fuji region. This Japanese motorcycle subculture dated back to the 1950s and regularly chafes with the police because of their provocative traffic behaviour and bike customising, that is often deemed illegal. (Photo by Thomas Peter/Reuters)

HIV-positive 71-year-old Sylverio Hachiploa (R) talks with caregivers Glandwel Muleya (L) and Sister Abigail Mwaka Mazuba (C) in his thatched hut during a visit by a home-based care team in the village of Nedwmba, south of the Chikuni Mission in the south of Zambia February 23, 2015. The caregivers in the Jesuit-run home-based care project at the Chikuni Mission run a capacity-building and empowerment project at the household level, offering training and assistance in crop-growing and animal rearing, as well as offering companionship, pastoral care and monitoring of the antiretroviral treatment compliance of HIV-AIDS patients. (Photo by Darrin Zammit Lupi/Reuters)

Aerial photography platform SkyPixel received 27,000 entries to its 2016 competition. Here are the winning shots plus some of our favourites. Here: Dam near perfect. Second prize in the same category was of the Huia Dam in Auckland, New Zealand. Hong Kong-based SkyPixel was launched in 2014. (Photo by Brendon Dixon/SkyPixel)

Cairo-based artist Chanel Arif's paints for her art project called After Dinner that uses humans and their surroundings as her canvas, in her gallery in the capital of Cairo, Egypt March 2, 2017. (Photo by Sherif Fahmy/Reuters)

Japan's Self-Defence Forces' women's personnel march during the annual SDF ceremony at Asaka Base, Japan, October 23, 2016. Some 40,00 troops, 280 military tanks and vehicles participated in the annual Japan's Self-Defense Forces parade. (Photo by Kim Kyung-Hoon/Reuters)

A Maasai moran athlete has his face smeared with red ocher paint during preparations for the 2016 Maasai Olympics at the Sidai Oleng Wildlife Sanctuary, at the base of Mt. Kilimanjaro, near the Kenya-Tanzania border in Kimana, Kajiado, Kenya December 10, 2016. (Photo by Thomas Mukoya/Reuters)