The Northern Lights glow green in a spectacular light show above a field of trees frozen solid with snow. (Photo by Jaak Sarv/Solent News & Photo Agency)

Michael Bath, from McLeans Ridges in New South Wales, Australia, estimates that in his lifetime he has taken more than 3,500 images of lightning bolts illuminating the sky. Photo: Alstonville, New South Wales, Australia – January 8, 2003. (Photo by Michael Bath/Caters News)

In this March 22, 1975 file photo, a refugee clutches a baby as a government helicopter gunship carries them away near Tuy Hoa, Vietnam, 235 miles northeast of Saigon. They were among thousands fleeing from Communist advances. AP Photographer Nick Ut will be retiring from the AP in March 2017 after 51 years of taking photographs from the front lines of the Vietnam War to the red carpets of Hollywood. (Photo by Nick Ut/AP Photo)

Boys ride a motorbike on their way back home after taking a bath in a canal at Chachura village, in Uttar Pradesh April 4, 2012. (Photo by Parivartan Sharma/Reuters)

People look at the Harmony of the Seas cruise ship leaving the STX shipyard of Saint-Nazaire, western France, for a three-day test offshore, on March 10, 2016. With a capacity of 6.296 passengers and 2.384 crew members, the Harmony of the Seas, built by STX France for the Royal Caribbean International, is the world's largest ship cruise. (Photo by Loic Venance/AFP Photo)

Boeing 747-400 of KLM in approach for the “Princess Juliana” airport, Netherlands Antilles Sint Maarten on July 2, 2002. (Photo by LUPOO/Ullstein Bild via Getty Images)

Rich Paul, Simon, Tristan Thompson, Khloe Kardashian, Lucas Newton, Kendall Jenner, Justine Skye, Jordan Woods and Kylie Jenner pose for a photo as Remy Martin celebrates Tristan Thompson's Birthday at Beauty in Los Angeles on March 1, 2018. (Photo by Jerritt ClarkJerritt Clark/Getty Images for Remy Martin)