Russian cosmonaut Alexander Skvortsov, Expedition 40 flight engineer, attired in a Russian Orlan spacesuit, participates in a session of extravehicular activity (EVA) in support of science and maintenance on the International Space Station on August 18, 2014. During the five-hour, 11-minute spacewalk, Skvortsov and cosmonaut Oleg Artemyev (out of frame) deployed a small science satellite, retrieved and installed experiment packages and inspected components on the exterior of the orbital laboratory. (Photo by NASA)

Fighters of the Free Syrian Army fire an anti-aircraft weapon in the rebel-held Mashhad area in southeastern Aleppo, on December 12, 2016, as they battle Syrian government forces during an operation to retake the embattled city. The crucial battle for Aleppo entered its “final phase” after Syrian rebels retreated into a small pocket of their former bastion in the face of new army advances. The retreat leaves opposition fighters confined to just a handful of neighbourhoods in southeast Aleppo, the largest of them Sukkari and Mashhad. (Photo by AFP Photo/Stringer)

“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)

In this February 5, 2014 photo, Divaldo Aguiar, who plays the part of Pachencho, is carried in a mock coffin during the Burial of Pachencho celebration, through a cemetery in Santiago de Las Vegas, Cuba. Cuban villagers stage a mock funeral and burial of Pachencho, with a living man playing the part of Pachencho, in a boozy festival that has become an annual tradition in this small town near Havana, held each February 5 for the last 30 years. (Photo by Enric Marti/AP Photo)

A small section of the expanding remains of the Veil Nebula, a massive star that exploded about 8,000 years ago. The entire nebula is 110 light-years across, covering six full moons on the sky as seen from Earth, and resides about 2,100 light-years away in the constellation Cygnus, the Swan. Image taken by NASA's Hubble Space Telescope. Released September 24, 2015. (Photo by Reuters/NASA/ESA/Hubble Heritage Team)

Festival goer practice yoga during the O.Z.O.R.A. festival on August 4, 2016 in Tolna, Hungary. Ozora is a village in Tolna County. In recent times it has become famous for the O.Z.O.R.A. psychedelic trance festival which has been held on an estate in Ozora near small village Dadpuszta every year since 2004. The first party was called Solipse and took place during the Solar eclipse of August 11, 1999. (Photo by Mohai Balázs/MTI/MTVA)

A woman is dragged away by Chinese men moments after she was seen talking to journalists near the site of a reported explosion outside the U.S. Embassy in Beijing, China, Thursday, July 26, 2018. A man exploded a small homemade bomb outside the U.S. Embassy in Beijing on Thursday, injuring only himself, according to police and an embassy spokesperson. (Photo by Ng Han Guan/AP Photo)

In this July 11, 2018 photo, members of a private photo studio take pictures of a woman in Havana, Cuba. New rules for private business indicate that the government has ruled out going further to open private business, such as allowing small and medium enterprises and authorizing business to operate as societies. Currently, private business licenses are granted only to individuals, and only one license per person. (Photo by Desmond Boylan/AP Photo)