This composite image shows a sequence, from bottom left to top left, of the moon's transition during a total lunar eclipse on April 15, 2014 in Miami, Florida. People in most of north and south America should be able to witness this year's first total lunar eclipse, which will cause a “blood moon” and is the first of four in a rare Tetrad of eclipses over the next two years. (Photo by Joe Raedle/Getty Images)

A devotee pulls a chariot during the Hindu festival of Thaipusam in Singapore February 9, 2017. (Photo by Edgar Su/Reuters)

A Kashmiri Shiite Muslim flagellates himself during a Muharram procession in Srinagar, Indian controlled Kashmir, Tuesday, October 11, 2016. Muharram is a month of mourning in remembrance of the martyrdom of Imam Hussein, the grandson of Prophet Mohammed. (Photo by Dar Yasin/AP Photo)

Rebel fighters from the Ahrar al-Sham Islamic Movement fire a heavy machine gun during what they said was an offensive to take the northwestern city of Idlib March 24, 2015. (Photo by Khalil Ashawi/Reuters)

Newly-wed Syrian couple Nada Merhi, 18, and Hassan Youssef, 27, have their wedding pictures taken in front of a heavily damaged building in the war ravaged city of Homs on February 5, 2016. A Syrian photographer thought of using the destruction of Homs to take pictures of newly wed couples to show that life is stronger than death. (Photo by Joseph Eid/AFP Photo)

A Russian trenchmortar crew run to take up a new firing position in the Stalingrad area during the Great Patriotic War. (Photo by Keystone/Getty Images). October 1942

German field telegraph operators at work in Warsaw. (Photo by Hulton Archive/Getty Images). 1st October 1914

Russian soldiers write home while serving on the Eastern Front during World War I, circa 1915. (Photo by Hulton Archive/Getty Images)