Astronauts Harrison Schmitt (left) and Eugene Andrew Cernan practice taking geological samples at the Kennedy Space Center in Florida, in preparation for NASA's scheduled Apollo 17 lunar landing mission, on August 28, 1972. Schmitt is the Lunar Module Pilot and Cernan is the mission's Commander. They are training for their period of EVA (extravehicular activity) on the Moon. (Photo by Space Frontiers/Getty Images)

A handout photo made available by the NASA shows the United Launch Alliance Delta IV Heavy rocket launches NASA's Parker Solar Probe to touch the Sun, from Launch Complex 37 at Cape Canaveral Air Force Station, Florida, USA, 12 August 2018. Parker Solar Probe is humanity’s first-ever mission into a part of the Sun’s atmosphere called the corona. Here it will directly explore solar processes that are key to understanding and forecasting space weather events that can impact life on Earth. (Photo by Bill Ingalls/EPA-EFE/NASA)

Back dropped by planet Earth the International Space Station (ISS) is seen from NASA space shuttle Endeavour after the station and shuttle began their post-undocking relative separation May 29, 2011 in space. After 20 years, 25 missions and more than 115 million miles in space, NASA space shuttle Endeavour is on the last leg of its final flight to the International Space Station before being retired and donated to the California Science Center in Los Angeles. Capt. Mark E. Kelly, U.S. Rep. Gabrielle Giffords' (D-AZ) husband, has lead mission STS-134 as it delivered the Express Logistics Carrier-3 (ELC-3) and the Alpha Magnetic Spectrometer (AMS-2) to the International Space Station. (Photo by NASA via Getty Images)

A model of the New Horizons spacecraft is seen at a live television program on NASA television celebrating the spacecraft's closest proximity to Pluto, at Johns Hopkins University Applied Physics Laboratory, site of the mission operations center, in Laurel, Maryland, USA, 14 July 2015. At approximately 7:49 am ET (11:49 am GMT), 14 July, New Horizons was scheduled to be as close to Pluto as the spacecraft will get; about 7,800 miles (12,500 kilometers) above the surface, following a journey of more than nine years and three billion miles. This is the first mission to the Pluto System and the Kuiper Belt. (Photo by Michael Reynolds/EPA)

A gopher tortoise walks the grounds of NASA's Kennedy Space Center in Florida, near the Vehicle Assembly Building on January 18, 2024. An all-European crew including Turkey's first astronaut are poised to blast off to the International Space Station in a mission with Axiom Space, as countries hungry for a taste of space turn increasingly to the private sector. (Photo by Chandan Khanna/AFP Photo)

Apollo 9 Command/Service Modules (CSM) nicknamed “Gumdrop” and Lunar Module (LM), nicknamed “Spider” are shown docked together as Command Module pilot David R. Scott stands in the open hatch. Astronaut Russell L. Schweickart, Lunar Module pilot, took this photograph of Scott during his EVA as he stood on the porch outside the Lunar Module. Apollo 9 was an Earth orbital mission designed to test docking procedures between the CSM and LM as well as test fly the Lunar Module in the relative safe confines of Earth orbit. (Photo by NASA)

ESA astronaut Tim Peake posted this stunning image on his social media channels, commenting: “Station passed through magnificent aurora Australis last night”. Tim is set to return to Earth on 18 June 2016, bringing his six-month Principia mission to the ISS to an end. During his stay he performed more than 30 scientific experiments for ESA and taking part in numerous others from ESA's international partners. ESA and the UK Space Agency have partnered to develop many exciting educational activities around the Principia mission, aimed at sparking the interest of young children in science and space. (Photo by Tim Peake/ESA/NASA)

NASA space shuttle Atlantis is prepared on the Vehicle Assembly Building floor at the Kennedy Space Center May 18, 2011 in Cape Canaveral, Florida. The space shuttle program ends with Atlantis mission STS-135 scheduled for early July. Space shuttle Atlantis will carry the Raffaello multipurpose logistics module to deliver supplies, logistics and spare parts to the International Space Station. Atlantis also will fly a system to investigate the potential for robotically refueling existing spacecraft and return a failed ammonia pump module. (Photo by Roberto Gonzalez/Getty Images)