In this Wednesday, July 23, 2014 file photo, Omaha photographer Lane Hickenbottom photographs the night sky in a pasture near Callaway, Neb. With no moon in the sky, the Milky Way was visible to the naked eye. More than one-third of the world’s population can no longer see the Milky Way because of man-made lights, according to a scientific paper by Light Pollution Science and Technology Institute's Fabio Falchi and his team members, published on Friday, June 10, 2016. (Photo by Travis Heying/The Wichita Eagle via AP Photo)

A picture made available on 09 October 2016 shows competitors during a Legion Run event, in Sofiko near the city of Corinth, Greece, 08 October 2016. Legion Run is run covering five kilometres with obstacles of mud, fire, ice and barbed wire, which takes place in different countries around the globe. (Photo by Vassilis Psomas/EPA)

Performers from the Joles ethnic group in Gambia prepare to perform with sharp blades which they say will demonstrate the magic powers of a spiritual water, that will make them immune to the cuts, during a campaign rally by incumbent President Yahya Jammeh, leader of the APRC (The Alliance for Patriotic Reorientation and Construction) in Bikama on November 24, 2016. As electoral favorite Jammeh seeks his fifth term in power, a two-week campaign period will come to an end next week ahead of the December 1st presidential election with political leaders canvassing in rural areas. (Photo by Marco Longari/AFP Photo)

This March 1, 2013 file photo shows a worker selecting cigars at the H. Upmann cigar factory, where people can take tours as part of the 15th annual Cigar Festival in Havana, Cuba. (Photo by Ramon Espinosa/AP Photo)

Members of the Indonesian Presidential Security Forces (Paspampres) show their skills during the simulation of a terrorist attack in Jakarta, Indonesia, 29 December 2016. According to reports in local media the Indonesian security forces have already arrested 21 terrorists suspects and fatally shot five of them, who were allegedly planning attacks in the Indonesian capital during the Christmas and New Year's Eve celebrations this year. The presentation was shown on the occasion of a visit by Indonesian President Joko Widodo and a delegation to the Paspampres headquarters in Jakarta. (Photo by Bagus Indahono/EPA)

Models promote a condom brand at the first Shenzhen s*x Culture Festival on September 21, 2007 in Shenzhen of Guangdong Province, China. The festival aims to increase awareness about reproductive health and popularise s*x education. (Photo by China Photos/Getty Images)

A Somali police officer arrests a suspected rebel member of the al Qaeda-affiliated al Shabaab among beach goers in Mogadishu. Al Shabaab claimed responsibility for today's pre-dawn attack on a Kenyan university campus near the Somali border. The following gallery examines who is al Shabaab. Here: Somali police officer (R) arrests a suspected rebel member (L) of the Al Qaeda-affiliated al Shabaab among beach goers at the Lido beach north of Somalia's capital Mogadishu March 23, 2012. (Photo by Feisal Omar/Reuters)

A mine detection rat is given banana as a reward after successfully identifying an inactive mine on July 2, 2015 in Siem Reap, Cambodia. The Cambodian Mine Action Center (CMAC) working with the Belgian NGO APOPO has recently begun testing the feasability of using large mine detection rats from Tanzania to help clear fields of mines and unexploded ordnance in one of the most bombed and mined countries in the world. (Photo by Taylor Weidman/Getty Images)