Mary McHugh mourns her slain fiance Sgt. James Regan at “Section 60” of the Arlington National Cemetery May 27, 2007. Regan, a US Army Ranger, was killed by an IED explosion in Iraq. (Photo by John Moore/Getty Images)

Villagers walk over a tree felled by rain in the village of Punta Caimanes, a place affected by heavy rains in the Izabal region, near Guatemala City, August 8, 2015. Heavy rains have affected eight communities in the municipality of El Estor and five in Livingston, both located in the region of Izabal, with five deaths due to floods, according to local media. (Photo by Josue Decavele/Reuters)

“I think as mothers we are all just trying our best”. – Gisele Bundchen. (Photo by Mads Nissen/AFP Photo)

A gallery assistant poses with the 1972 work “Secretary” at a press viewing of the artist's exhibition “Allen Jones RA” at the Royal Academy of Arts in London November 11, 2014. (Photo by Neil Hall/Reuters)

These are the dunes of the Namib Desert, taken by Korea's Kompstat-2 satellite. The blue and white area is the dried riverbed of the Tsauchab river. (Photo by The European Space Agency)

Yaroslav Segeda at the top of a high rise building in Kudrinskaya Square, Moscow, Russia. (Photo by Yaroslav Segeda/Caters News)

A red fox sits in front of a Eurofighter Typhoon combat jet on the grounds of the 2014 ILA Berlin Air Show, in Selchow near Schoenefeld, Germany, Thursday, May 15, 2014. The International Aviation and Aerospace Exhibition ILA will take place from May 20 until May 25, 2014. (Photo by Patrick Pleul/AP Photo/DPA)