“What created this unusual hole in Mars? The hole was discovered by chance on images of the dusty slopes of Mars' Pavonis Mons volcano taken by the HiRISE instrument aboard the robotic Mars Reconnaissance Orbiter currently circling Mars”. (Photo by NASA/JPL/University of Arizona)

“Entwined Lives”. Tim Laman, US Winner, Wildlife photographer of the year. A young male orangutan makes the 30-metre climb up the thickest root of the strangler fig high above the canopy in Gunung Palung national park, one of the few protected orangutan strongholds in Indonesian Borneo. Laman had to do three days of climbing to position several GoPro cameras that he could trigger remotely. This shot was the one he had long visualised, looking down on the orangutan within its forest home. (Photo by Tim Laman/2016 Wildlife Photographer of the Year)

A supercell thunderstorm develops, May 8, 2017 in Elbert County outside of Limon, Colorado. With funding from the National Science Foundation and other government grants, scientists and meteorologists from the Center for Severe Weather Research try to get close to supercell storms and tornadoes trying to better understand tornado structure and strength, how low-level winds affect and damage buildings, and to learn more about tornado formation and prediction. (Photo by Drew Angerer/Getty Images)

A participant, called a musher, races in the 33rd Aviemore Sled Dog Rally in Aviemore, Scotland January 23, 2016. The Siberian Husky Club of Britain is holding its annual sled dog rally over the weekend. (Photo by Russell Cheyne/Reuters)

U.S. Air Force pilots with the Thunderbirds perform the calypso pass maneuver in F-16 Fighting Falcon aircraft during a practice session prior to the Gunfighter Skies air show at Mountain Home Air Force Base, Idaho, September 19 and released September 24, 2014. (Photo by Tech. Sgt. Manuel J. Martinez/Reuters/US Air Force)

The antennas of the European Southern Observatory's Atacama Large Millimeter/Submillimeter Array, also known as ALMA, are set against the splendor of the Milky Way in this picture by Babak Tafreshi. Construction of the full ALMA array is due to be completed in Chile's Atacama Desert in 2013, but the facility is already making scientific observations with a partial array of antennas. (Photo by ESO/B. Tafreshi/TWAN)

A policeman looks at a car crushed underneath a collapsed bridge in Belo Horizonte, Brazil, Thursday, July 3, 2014. The overpass under construction collapsed Thursday in the Brazilian World Cup host city. The incident took place on a main avenue, the expansion of which was part of the World Cup infrastructure plan but, like most urban mobility projects related to the Cup, was not finished on time for the event. (Photo by Victor R. Caivano/AP Photo)