NASA says it could be another 20 years before humans touch down on Mars, but in a sense, the Mars Society has been exploring the red planet for more than a decade – in Utah. Photo: Csilla Orgel, a geologist of Crew 125 EuroMoonMars B mission, makes her way back to the Mars Desert Research Station (MDRS) in the Utah desert March 3, 2013. The MDRS aims to investigate the feasibility of a human exploration of Mars and uses the Utah desert's Mars-like terrain to simulate working conditions on the red planet. Scientists, students and enthusiasts work together developing field tactics and studying the terrain. All outdoor exploration is done wearing simulated spacesuits and carrying air supply packs and crews live together in a small communication base with limited amounts of electricity, food, oxygen and water. Everything needed to survive must be produced, fixed and replaced on site. (Photo by Jim Urquhart/Reuters)

Tao Xiangli gets out of his homemade submarine after operating it in a lake on the outskirts of Beijing September 3, 2009. Amateur inventor Tao, 34, made a fully functional submarine, which has a periscope, depth control tanks, electric motors, manometer, and two propellers, from old oil barrels and tools which he bought at a second-hand market. He took 2 years to invent and test the submarine which costs 30,000 yuan ($4,385). (Photo by Christina Hu/Reuters)

Passengers wait for a train to depart from the Hankou Railway Station in Wuhan, central China's Hubei province, Friday January 13, 2017. Officials expect that Chinese travelers will make almost 3 billion trips during the holiday travel rush that starts runs through Feb. 21. These trips include intercity flights, trains and local bus rides to villages for China's 1.4 billion people. (Photo by Chinatopix via AP Photo)

A U.S. Navy F18 fighter jet takes off from aircraft carrier USS Carl Vinson during a FONOPS (Freedom of Navigation Operation Patrol) in South China Sea, March 3, 2017. The U.S. military took journalists Friday to the carrier on routine patrol off the disputed South China Sea, sending a signal to China and American allies of its resolve to ensure freedom of navigation and overflight in one of the world's security hotspots. (Photo by Erik De Castro/Reuters)

A handout photo made available by TeideLab shows an image composed of 200 pictures that shows the lightning activity between 3 am and 7am during a storm in Izana, Tenerife, Canary Islands, Spain, 27 October 2019. Over 2,000 lighting strikes fell mostly over Tenerife island last 26 October during a strong storm. (Photo by Daniel López/EPA/EFE/TeideLab)

Crowds on the beach in Cape Canaveral, Fla., watch the launch of the SpaceX Falcon 9 Crew Dragon on its Crew-1 mission carrying four astronauts, Sunday, November 15, 2020, in this 3 1/2-minute time exposure. The rocket was launched from Launch Complex 39A at Kennedy Space Center at 7:27 p.m. Sunday evening. (Photo by Malcolm Denemark/Florida Today via AP Photo)

A woman takes part in a protest at Parliament Square, following the kidnap and murder of Sarah Everard, in London, Britain March 15, 2021. Everard, 33, was abducted as she walked home in south London on March 3 and a police officer has been charged with her kidnap and murder, provoking a national debate over how British society deals with male violence against women. (Photo by Henry Nicholls/Reuters)

A woman passes Members of historical clubs dressed in the uniform of French soldiers during ceremony of repatriation of the remains of French General Charles-Etienne Gudin de la Sablonniere, participant in the French Revolutionary wars and Napoleonic wars, to France in Moscow airport Vnukovo-3, Russia, 13 July 2021. (Photo by Sergei Ilnitsky/EPA/EFE)