A girl in a military uniform poses for a photo after the see-off ceremony before the launch in Jiuquan, Gansu province, China, 25 April 2024. China's Shenzhou-18 manned spaceflight mission with three astronauts is the third manned spaceflight mission of China Space Station's development phase. The mission will last for about six months and the crew will carry out tasks such as installation, commissioning, maintenance, repair, and experiments in space. (Photo by Wu Hao/EPA/EFE)

(L-R), Pilot Gregory H. Johnson, European Space Agency astronaut Roberto Vittori, Mission Specialist Greg Chamitoff, Commander Mark Kelly, Pilot Gregory H. Johnson, Mission Specialist Michael Fincke, and Mission Specialist Andrew Feustel, participate in a Terminal Countdown Demonstration Test (TCDT), at the Kennedy Space Center, on April 1, 2011 in Cape Canaveral, Florida. The TCDT will culminate in a full dress rehearsal for the planned April 19th launch of Space Shuttle Endeavour’s final scheduled flight to the International Space Station before being retired. (Photo by Mark Wilson/Getty Images)

The NASA Extreme Environment Mission Operations (NEEMO) 21 mission began on July 21 as an international crew of aquanauts splashed down to the undersea Aquarius Reef Base, located 62 feet below the surface of the Atlantic Ocean in the Florida Keys National Marine Sanctuary. The NEEMO 21 crew will perform research both inside and outside the habitat during a 16-day simulated space mission. During simulated spacewalks carried out underwater, they will evaluate tools and mission operation techniques that could be used in future space missions, including journeys to Mars. (Photo by Karl Shreeves/NASA)

This February 7, 2018, photo shows João Lousada, a flight controller for the International Space Station, wearing an experimental space suit during a simulation of a future Mars mission in the Dhofar desert of southern Oman. The desolate desert in southern Oman resembles Mars so much that more than 200 scientists from 25 nations organized by the Austrian Space Forum are using it for the next four weeks to field-test technology for a manned mission to Mars. (Photo by Sam McNeil/AP Photo)

In this photo taken on Thursday, August 22, 2019, and distributed by Roscosmos Space Agency Press Service, the Russian Progress 73 cargo ship blasts off from the launch pad at Russia's space facility in Baikonur, Kazakhstan. The new Russian rocket, that is expected to replace the current model sending manned missions into space, blasted off from Kazakhstan on Thursday, carrying a Soyuz capsule with a humanoid robot. (Photo by Roscosmos Space Agency Press Service via AP Photo)

A woman holds up the Chinese national flag as people gather to watch the the launch of the Long March 5B rocket carrying China's Tianhe space station core module from the Wenchang Spacecraft Launch Site in Hainan Province, China, 29 April 2021. China launched into space the core module of its space station, marking the beginning of a series of launch missions to complete the space station by the end of next year. (Photo by Matjaz Tancic/EPA/EFE)

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)

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)