Merit: A Night at Deadvlei. The night before returning to Windhoek, we spent several hours at Deadveli. The moon was bright enough to illuminate the sand dunes in the distance, but the skies were still dark enough to clearly see the milky way and magellanic clouds. Deadveli means “dead marsh. The camelthorn trees are believed to be about 900 years old, but have not decomposed because the environment is so dry. (Photo and caption by Beth McCarley/National Geographic Traveler Photo Contest)

A Nepalese army solder stand next to a horse during the “Ghodejatra” Horse Race festival, which is organised by the Nepal Army, in Kathmandu, Nepal, April 7, 2016. Ghode Jatra, the horse racing festival of Nepal, celebrated on the New Moon day of mid March or early April is among the important celebrations of the Kathmandu Valley. Grand horse parade including various acrobatic style of shows are performed by Nepal military at Tundikhel-a fenced parade ground located in the heart of Kathmandu city. (Photo by Navesh Chitrakar/Reuters)

An Indian labourer sifts coloured powder, known as “gulal”, to be used during the forthcoming spring festival of Holi, inside a factory at Fulbari village on the outskirts of Siliguri on March 6, 2017. Holi, the popular Hindu spring festival of colours is observed in India at the end of the winter season on the last full moon of the lunar month, and will be celebrated on March 13 this year. (Photo by Diptendu Dutta/AFP Photo)

“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)

Brad Snead walks past melting ice on the Cook Inlet beach, Saturday, March 26, 2011, in Kenai, Alaska, while looking for agates. (AP Photo/Peninsula Clarion, M. Scott Moon)

A lioness bares its teeth inside an enclosure after a raid at a zoo-like house on the outskirts of Bangkok, Thailand Monday, June 10, 2013. Thai police and forestry officials searched and seized a number of imported and endangered animals including 14 lions from Africa and arrested the house's owner. (Photo by Apichart Weerawong/AP Photo)

A woman looks out of her house with a decorated doorway during Corpus Christi day in Zahara de la Sierra, southern Spain, May 29, 2016. The village of Zahara de la Sierra celebrated the feast of Corpus Christi (or Body of Christ in Latin) by covering the streets and facades of houses with the branches of trees and grass. (Photo by Jon Nazca/Reuters)

Belarusian villagers celebrate the Christmas carol rite (Kalyady) in the village of Danilevichy, some 320 km south of Minsk on January 7, 2020. Kalyady is an ancient pagan holiday originally celebrated on winter solstice. Dressed-up people walk from house to house singing, dancing, eating and drinking with their neighbours. (Photo by Sergei Gapon/AFP Photo)