“NASA's Mars rover Opportunity just celebrated its ninth anniversary on Mars – a mission that was originally meant to last just 90 days...” – The Atlantic. Photo: NASA's rover Opportunity visits Victoria Crater, viewed from orbit by the High Resolution Imaging Science Experiment on NASA's Mars Reconnaissance Orbiter in october of 2006. Opportunity is a small dot on the crater's lip, at top right. Opportunity first reached the crater's rim on September 27, 2006. (Photo by NASA/JPL-Caltech/University of Arizona via The Atlantic)

Infantrymen of the US First Army shake hands with Russian soldiers on the broken bridge over the Elbe after the link-up at Torgau, Germany. The US soldiers are (L-R): Pfc. John A Metzger, Delbert E Philpott, and Pvt. Thomas B Summers; all are from A Company, 271st Regiment. (Photo by Allan Jackson/Getty Images). 04-1945

Freshmen in Zhengzhou Institute of Aeronautical Industry Management head bottles of mineral water for upright stand during military training on September 17, 2015 in Zhengzhou, Henan Province of China. More than 6,800 freshmen in the school are required to take part in the military training. (Photo by ChinaFotoPress/ChinaFotoPress via Getty Images)

Engine driver Josef Kowatsch (top L) steers a train through the NEAT Gotthard Base Tunnel during a media visit near the town of Erstfeld August 24, 2015. Crossing the Alps, the world's longest train tunnel should become operational at the end of 2016, consisting of two parallel single track tunnels, each of a length of 57 km (35 miles). (Photo by Arnd Wiegmann/Reuters)

A Yorkshire Terrier has it's hair done on a grooming table on Day one of Crufts at the Birmingham NEC Arena on March 8, 2012 in Birmingham, England. During the annual four-day competition nearly 22,000 dogs and their owners will compete in a variety of categories, ultimately seeking the coveted prize of “Best In Show”. (Photo by Dan Kitwood/Getty Images)

Some of the best entries so far in the 2016 Insight Astronomy Photographer of the Year competition. There are two weeks left to enter, and the winners will be announced in September. Here: Aurora over Laksvatn Fjord, Laksvatn, Norway. The aurora borealis dances in the skies over the town of Laksvatn, with the Milky Way to the left. The image is a single shot with no compositing, only post-processing to bring out the aurora, and some colour corrections. The photographer Matt Walford said: “I love the way the northern lights look like they are just wistfully dancing over the fjord, framed by the mountains on either side”. (Photo by Matt Walford/National Maritime Museum)

A student, wearing a traditional costume and headdress, stands in line for interviews during a recruitment held by an airline company, hoping to stand out from more than 500 candidates for airline stewardess positions, in Chengdu, Sichuan Province, China, May 27, 2016. (Photo by Reuters/Stringer)

In this Saturday, July 4, 2015 photo, Israeli and Russian members of knight clubs cook their breakfast before the reenactment of the Battle of Hattin in Lavi Forest, northern Israel. About a third of the participants arrived with their elaborate gear from Russia. The project is supported by the Lower Galilee Regional Council. (Photo by Oded Balilty/AP Photo)