A tourist stands on the shore of a private beach in Naama Bay, Sharm el-Sheikh, south Sinai, Egypt, Sunday, November 8, 2015. Britain's foreign secretary says airport security in many cities will need to be overhauled if it is confirmed the Russian plane crash in the Sinai was caused by a bomb planted by the Islamic State group or someone inspired by the militants. (Photo by Vinciane Jacquet/AP Photo)

Two men try to load their just purchased Samsung 55" TV into a car, at a Best Buy store in Fairfax, Virginia on November 26, 2015, on a Black Friday sale that started a day earlier during Thanksgiving evening. The US holiday shopping season kicks off with "Black Friday" – the day after the Thanksgiving holiday – with a frenzy expected at stores around the country as retailers slash prices. (Photo by Paul J. Richards/AFP Photo)

A reveller (R), dressed as “Diablos de Luzon” (Luzon Devils), stands next to a person dressed as a “Mascaritas” during carnival celebrations in the village of Luzon, Spain, February 6, 2016. The “Diablos” cover themselves in a mixture of soot and oil and adorn their heads with black-stained bull horns as they parade throughout the village with cowbells clanging around their waists to expel the evil spirits. (Photo by Sergio Perez/Reuters)

Vendors sell clothes on the roadside at a second-hand street side clothing market in Mumbai January 28, 2015. The market is open daily for three hours and hundreds of vendors gather to barter or sell used clothing. (Photo by Danish Siddiqui/Reuters)

A boy holds his mother's leg as he cries in front of their damaged house after a strong 6.6 magnitude earthquake at Longmen village, Lushan county in Ya'an, Sichuan province. (Photo by Jason Lee/Reuters)

Participants adjust their make up backstage during a breast model contest in Hefei, Anhui province September 24, 2014. Over 100 models participated in this contest, which was held by a cosmetic company. The winner was awarded 680,000 yuan ($110,825) as cosmetic funds and 30,000 yuan ($4,890) in cash, local media reported. (Photo by Reuters/Stringer)

Women pose for a selfie at Ipanema Beach in Rio de Janeiro, Brazil on July 30, 2016. (Photo by Nacho Doce/Reuters)

The NASA Extreme Environment Mission Operations (NEEMO) 21 mission began on July 21 as an international crew of aquanauts splashed down to the undersea Aquarius Reef Base, located 62 feet below the surface of the Atlantic Ocean in the Florida Keys National Marine Sanctuary. The NEEMO 21 crew will perform research both inside and outside the habitat during a 16-day simulated space mission. During simulated spacewalks carried out underwater, they will evaluate tools and mission operation techniques that could be used in future space missions, including journeys to Mars. (Photo by Karl Shreeves/NASA)