“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)

“The RSPB’s Snettisham Nature Reserve lies on the edge of The Wash, one of the most important bird estuaries in the United Kingdom. The Wash, on England’s east coast, supports over 300,000 birds, and Snettisham sometimes holds more than a third of them”. – The Palm Beach Post. Photo: Waders flock together seeking new feeding grounds during the incoming tide. (Photo by Dan Kitwood/Getty Images via The Palm Beach Post)

Rangoli, also known as kolam or Muggu, is a folk art from India in which patterns are created on the floor in living rooms or courtyards using materials such as colored rice, dry flour, colored sand or flower petals. It is usually made during Diwali, Onam, Pongal and other Indian festivals. They are meant to be sacred welcoming areas for the Hindu deities. The ancient symbols have been passed down through the ages, from each generation to the next, keeping both the art form and the tradition alive. Similar practices are followed in different Indian states: in Tamil Nadu, there is Kolam in Tamil Nadu; Mandana in Rajasthan; Chaookpurna in Chhattisgarh; Alpana in West Bengal; Aripana in Bihar; Chowk pujan in Uttar Pradesh; Muggu in Andhra Pradesh and others.

An anti-Gaddafi fighter tests an anti-aircraft gun southwest of Sirte, Libya one of Muammar Gaddafi's last remaining strongholds, September 16, 2011. A timeline of images dating from 2010 from Sirte, Libya, the home town of deposed Libyan leader Muammar Gaddafi. Libyan forces battling Islamic State in the city of Sirte say they have defeated the militant group after months of street to street fighting backed by U.S. air strikes. Islamic State took control of the city more than a year ago and set up its main base outside Syria and Iraq. (Photo by Goran Tomasevic/Reuters)

A humanoid robot named “Yangyang” shows a facial expression during its demonstration at the Global Mobile Internet Conference (GMIC) 2015 in Beijing, China, April 29, 20155. The android was produced jointly by China's Shanghai Yangyang Intellegent Robot Science Service center and Japanese professor Hiroshi Ishiguro, with the aim of popularising robotics among the young. (Photo by Kim Kyung-Hoon/Reuters)

Mayon Volcano spews ash and lava in the town of Daraga, Albay province, Philippines, 25 January 2018. Mayon volcano located in eastern Philippines and active over the last 10 days spewed fresh lava and ash while the number of evacuees exceeded 60 thousand in the face of the threat of an even more potent explosion. The Philippines, which currently has 23 active volcanoes, is situated on the so-called 'Pacific Ring of Fire', an area known for its intense seismic activity which extends from the west coast of the American continent to New Zealand, Japan, the Philippines and Indonesia. (Photo by Francis R. Malasig/EPA/EFE)

Two men fight in San Jose, Costa Rica, during the Women's Day on March 8, 2014. (Photo by Jeffrey Arguedas/EFE/SIPA Press)

An Iraqi Muslim woman walks past Christmas decorations for sale in the Shiite holy city of Najaf on December 17, 2015. (Photo by Haidar Hamdani/AFP Photo)