Balal, who killed Iranian youth Abdolah Hosseinzadeh in a street fight with a knife in 2007, is brought to the gallows during his execution ceremony in the northern city of Nowshahr on April 15, 2014. The mother of Abdolah Hosseinzadeh spared the life of the her son's convicted murderer, with an emotional slap in the face as he awaited execution prior to removing the noose around his neck. (Photo by Araash Khamooshi/AFP Photo/ISNA)

A giant Rubber Duck created by Dutch artist Florentijn Hofman is towed along Hong Kong's Victoria Habour Thursday, May 2, 2013. Since 2007 the 16.5-meter (54 feet)-tall Rubber Duck has traveled to various cites including Osaka, Sydney, Sao Paulo and Amsterdam. (Photo by Vincent Yu/AP Photo)

"Steve McCurry: India", co-organized by the Rubin Museum and the International Center of Photography, brings together photographs of India-its people, monuments, landscapes, seasons, and cities. The exhibition at the Rubin Museum in New York runs from November 18, 2015 – April 4, 2016. Here: A boy in mid-flight in Jodhpur, Rajasthan, India, in 2007. (Photo by Steve McCurry)

An Airbus A380 aircraft prepares to land at Mumbai airport in this May 8, 2007 file photo. Sentiment at some of Asia's biggest firms deteriorated again in the fourth quarter, falling to a four-year low under the weight of concerns about slowing growth in China, the region's biggest economy, a Thomson Reuters/INSEAD survey showed. (Photo by Arko Datta/Reuters)

“Kumbh Mela is a mass Hindu pilgrimage in which Hindus gather at the Ganges river. The normal Kumbh Mela is celebrated every 3 years, the Ardh (half) Kumbh Mela is celebrated every six years at Haridwar and Prayag, the Purna (complete) Kumbh takes place every twelve years, at four places (Prayag (Allahabad), Haridwar, Ujjain, and Nashik). The Maha (great) Kumbh Mela which comes after 12 “Purna Kumbh Melas”, or 144 years, is held at Allahabad.

The last Ardh Kumbh Mela was held over a period of 45 days beginning in January 2007, more than 70 million Hindu pilgrims took part in the Ardh Kumbh Mela at Prayag, and on January 15, the most auspicious day of the festival of Makar Sankranti, more than 5 million participated. The previous Maha Kumbh Mela, held in 2001, was attended by around 60 million people, making it at the time the largest gathering anywhere in the world in recorded history”. – Wikipedia

Photo: Sadhus (holy men) smoke at their camp near the ritual site at Sangam, the confluence of the Ganges, Yamuna and mythical Saraswati rivers during the Ardh Kumbh Mela festival (Half Pitcher festival) January 18, 2007 in Allahabad, India. Millions of Hindu pilgrims have flocked to the largest religious gathering in the world which lasts for 45 days in northern India. The festival commemorates the mythical conflict between gods and demons over a pitcher filled with the “nectar of immortality”. Devotees believe that taking a holy dip in the Ganges at this time washes away their sins and paves the path to salvation. (Photo by Mario Tama/Getty Images)

World War Two veteran Abla Begaliyev, 91, is seen in an undated handout picture (L), poses for a picture in Arashan (Top R) and at home in Kyrgyzstan April 14, 2015. Begaliyev served in the border guard cavalry from February 1942 until April 1947. Originally from Kyrgyzstan, he fought on the Ukrainian front and relocated to the border with Afghanistan at the end of World War Two. As the world marks the 70th anniversary of the end of World War Two, Reuters photographers the length and breadth of the former Soviet republics (CCCP) captured portraits of Red Army veterans, mostly now in their 80s and 90s, today and through archive pictures at the time. More than 20 million Soviet citizens were killed in the war. (Photo by Vladimir Pirogov/Reuters/Family handout (L))

Workers demonstrate outside the factory of Hua Yang Printing Holdings Co Ltd on October 30, 2007 in Shenzhen of Guangdong Province, China. Over 1,000 workers of the company have blocked the 107 State Highway where the firm is located, to protest against their employer, who owed half a month's salary to the workers. (Photo by China Photos/Getty Images)

“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)