Amateur astronomer Bill Snyder has been involved with astrophotography since 2007. Photo: The Cygnus Wall is in the southern area of NGC7000 also known as the North America Nebula. It is approximately 1800 light years from Earth, and is in the constellation Cygnus. The Wall is an energized shock front and contains the most concentrated star formations in the nebula. The size of the North America Nebula is about 4 full moons. (Photo and caption by Bill Snyder)

“Cassowaries are large, flightless birds related to emus and (more distantly) to ostriches, rheas, and kiwis”, writes Olivia Judson in the September issue of National Geographic magazine. How large? People-size: Adult males stand well over five foot five and top 110 pounds. Females are even taller, and can weigh more than 160 pounds. Dangerous when roused, they’re shy and peaceable when left alone. But even birds this big and tough are prey to habitat loss. The dense New Guinea and Australia rain forests where they live have dwindled. Today cassowaries might number 1,500 to 2,000. And because they help shape those same forests – by moving seeds from one place to another – “if they vanish”, Judson writes, “the structure of the forest would gradually change” too. (Photo by Christian Ziegler/National Geographic)

Liu Chunxia, a supporter of Xu Zhiyong, one of China's most prominent rights advocates, is detained by policemen while she gathers with other supporters nearby a court where Xu's trial is being held in Beijing January 22, 2014. When dozens of activists unfurled banners across the country last March and April calling for officials to disclose their assets, they did so at the urging of one of China's most prominent rights advocates, Xu Zhiyong. Xu, 40, stands trial on Wednesday on a charge of “gathering a crowd to disturb public order” punishable by up to five years in prison. His case will almost certainly spark fresh criticism from Western governments over Beijing's crackdown on dissent. (Photo by Kim Kyung-Hoon/Reuters)

A girl sticks out her tongue during snowfalls on a street in Hefei, Anhui province February 13, 2014. (Photo by Reuters/Stringer)

“Leopard Hunting a Stork”. “One-shot capture. I watched the leopard stalking the stork, I only had time to focus at 400mm, no time to change to high speed, I watched the stork, and as soon as it flapped its wings, I shot one shot”. (Photo by Paul Rifkin/National Geographic Travel Photographer of the Year Contest)

A Nepalese man sits outside a Hindu temple as a goat rests on a parked scooter in Khokana, Lalitpur District, Nepal, Monday, September 26, 2016. Writing on the wall offers prayers to Hindu god Shiva. (Photo by Niranjan Shrestha/AP Photo)

Zombie Boy, who holds a Guinness World Record for most bones inked on a human body, gave Londoners a fright on October 5, 2016 as he was spotted at commuter hotspots across the capital to promote Thorpe Park’s new Halloween attraction. Canadian born Zombie Boy has 90% of his body covered in tattoos with a value of over $20,000 in total, including an entire skeleton and skull on his face, visited Canary Wharf, Oxford Street and Soho. (Photo by Rex Features)

A frog appears to have a big smile for the camera, Russia. Things are heating up at the Comedy Wildlife Photography Awards as the shortlisted final 40 entries are revealed. This year's competition has featured over 2200 hilarious entries from around the world with photos including a fox face planting in the snow, a dancing brown bear and a pair of seemingly headless penguins – all beautifully photographed with perfect comedy timing and a strong conservation message. (Photo by Artyom Krivosheev/Barcroft Images/Comedy Wildlife Photography Awards 2016)