These Northern Lights “rainbows” have turned the sky greener than the Earth below. Vitaly Istomin, 26, spent several nights in freezing conditions under the stars in northern Russia’s Khibiny Mountains to capture the aurora’s “rainbows”. (Photo by Vitaly Istomin/Caters News Agency)

A girl in a swimsuit participates in the BoogelWoogel alpine carnival at the Rosa Khutor Alpine Resort in Krasnaya Polyana, Sochi, Russia on March 31, 2018. (Photo by Artur Lebedev/TASS)

An employee walks near a rotary dredge which works on the coal face of the Borodinsky opencast colliery, near the Siberian town of Borodino, east of Krasnoyarsk, December 9, 2014. The Borodinsky colliery, 9 km (5.6 miles) long and more than 100 meters (328 feet) deep, annually produces more than 20 million tons of coal and is considered to be the biggest opencast coal mine in Russia, according to official representatives. (Photo by Ilya Naymushin/Reuters)

Every year, in the Rostov region of Russia, a group of 40 young and not so young rural workers compete in the Bison Track Show, or more affectionately known as: Russian Flying Tractor Racing. In front of crowds numbering up to 30,000 people, a series of smoke spilling, monstrous farming machines tear round an 8km mud track, plowing through lakes and dirt mounds, their turbos screaming and tyres scrabbling to find grip.

A mobile phone cover with a picture of Russian President Vladimir Putin and which reads “Mr President” is seen in this photo illustration taken a in hotel room in Kazan, Russia, July 30, 2015. He may be in charge of an economy in crisis, but if mobile phone covers and souvenir mugs are a barometer of popularity, Russian President Vladimir Putin need not fear for his political future. In fact, Moscow's annexation of Crimea from Ukraine last year has given the memorabilia makers even more material to glorify, sometimes wryly, a president whose image as a champion of Russian national interests in a hostile world is barely challenged in his own country. (Photo by Stefan Wermuth/Reuters)

A Husky dog looks on before a sled and skijoring race in the village of Kadnikovo outside Yekaterinburg, Russia, December 10, 2016. (Photo by Maxim Shemetov/Reuters)

A woman applies lipstick in a car that is parked at a beach facing a volcanic rock called Devil's Finger outside Yuzhno-Kurilsk, the main settlement on the Southern Kurile island of Kunashir September 15, 2015. Russian residents of the island chain at the centre of a dispute between Japan and Russia that has held up a treaty to formally end World War Two hope a diplomatic solution will lure tourists and investment to help refurbish rickety infrastructure. The Southern Kuriles are referred to in Japan as the Northern Territories. (Photo by Thomas Peter/Reuters)

Fire fighters, emergency service vehicles and a helicopter in Moskovsky Prospekt at the entrance to Tekhnologichesky Institut station of the St Petersburg metro in the aftermath of an explosion which occurred in a train at 14:40 Moscow timeon April 3, 2017. (Photo by Peter Kovalev/TASS)