“Contrails (short for “condensation trails”) or vapour trails are artificial clouds that are the visible trails of condensed water vapour made by the exhaust of aircraft engines. As the hot exhaust gases cool in the surrounding air they may precipitate a cloud of microscopic water droplets or, if the air is cold enough, tiny ice crystals”. – Wikipedia

Photo: An airplane leaves a vapor trail as it flies in front of he moon on January 17, 2007 above Hanover, Germany. (Photo by Alexander Hassenstein/Getty Images)

July 23, 2013 – Kampala, Uganda. Helene and Diana train daily more than 2.5 hours by Innocent Kapalata, a passionate and ambitious former boxer. Amidst the shanty homes a group of ambitious fighters are trying to reach for a better life. (Photo by Peter Bauza/ZUMA Press/VISUAL Press)

Sukhoi Su-30SM jet fighters of the Sokoly Rossii (Falcons of Russia) aerobatic team fly in formation during the International Army Games 2016, in Dubrovichi outside Ryazan, Russia, August 5, 2016. (Photo by Maxim Shemetov/Reuters)

Members of ASC Tornados, the motorcycle display team of the Indian army, lie in a row on the ground as another performs a stunt by jumping over them during the 225th anniversary celebrations of Army Service Corps in Bangalore, India, Tuesday, December 8, 2015. The Army Service Corps which was established in 1790 is an arm of the Indian Army which handles its logistic support function. (Photo by Aijaz Rahi/AP Photo)

Two hippopotamus are fed with pumpkins at the Hanoi Zoo, in Hanoi, Vietnam, 25 October 2018. The zoo has been the home for more than 800 animals of over 90 different species, including three hippopotamus, since it was built in 1976. (Photo by Luong Thai Linh/EPA/EFE)

A referee tries to separate two cocks fighting during a Cock fighting tournament on December 3, 2016 on the outskirts of Antananarivo, Madagascar. Cockfighting is held during the week end and is a tradition with asian roots still practiced in Madagascar. (Photo by Gianluigi Guercia/AFP Photo)

“Wombats are Australian marsupials; they are short-legged, muscular quadrupeds, approximately 1 metre (39 in) in length with a short, stubby tail. They are adaptable in their habitat tolerances, and are found in forested, mountainous, and heathland areas of south-eastern Australia, including Tasmania, as well as an isolated patch of about 300 ha in Epping Forest National Park in central Queensland”. – Wikipedia

Photo: “Abdul”, a baby Common Wombat, is one of the marsupials on show during the spring baby boom at Taronga Zoo September 1, 2005 in Sydney, Australia. “Abdul” was orphaned when his mother was killed by a car. (Photo by Mark Nolan/Getty Images)

A passenger plane comes into land over a field containing horses at Heathrow Airport on August 11, 2014 in London, England. Heathrow is the busiest airport in the United Kingdom and the third busiest in the world. The airport's operator BAA wants to build a third runway to cope with increased demand. (Photo by Peter Macdiarmid/Getty Images)