The last Apollo mission, Apollo 17, took place in 1972. It was the last time humans traveled past low-Earth orbit — the nearest route around the planet in which space stations and most crewed space vehicles and artificial satellites dwell. By the time the Apollo 11 sent the first humans to the moon in July 1969, priorities for crewed space missions had already changed. Expensive moon missions were scrapped for the promise of regular, cheaper missions to Earth orbit.

U.S. President Richard Nixon appointed a Space Task Group just after taking office in January 1969. The Space Task Group recommended a lunar space base, a mission to Mars, an Earth-orbiting space station and a reusable space plane. Only the space station and the space plane (the space shuttle) came to be.

NASA’s space shuttle made its debut when Columbia went into orbit in 1981. Originally, the space shuttle was meant to be a workhorse, providing a relatively inexpensive way to perform experiments, as well as a way to send cargo to space stations and satellites into orbit about 50 times a year. The shuttle averaged about four launches a year at a much higher cost than expected.

Initially, Soviet leadership feared the U.S. could use the shuttle as a nuclear-armed orbital bomber. That fear was not without merit. Space technology is often developed for military purposes. The same rocket technology that sends humans into space for civilian purposes also sends ICBMs through space to their targets. This framing provided the U.S. government with a modicum of plausible deniability with the tension of the Cold War and possible nuclear annihilation. The most contentious aspect of the space program was the laser-based anti-ICBM system proposed by U.S. President Ronald Reagan, disparagingly known as Star Wars after the 1977 blockbuster movie. However, it never materialized.

Germany built the first mass-produced rockets, the V-2, during World War II as a long-range weapon. The V-2 was a ballistic missile. Those who designed the V-2 later developed the first rockets for the U.S. Department of Defense at Redstone Arsenal and for the Soviet military, the Redstone rocket and the R-1 rocket, respectively. Eventually, the R-1 changed into the R-7, which launched Sputnik. Similarly, a modified Redstone, Jupiter-C, launched the first U.S. satellite, Explorer.

Other nations that developed early orbital-launching capability also started these as military projects. France’s Diamant rocket, which launched the Astérix satellite in 1965, originated from a series of ballistic missiles. In 1970, China’s Long March 1 sent the Dong Fang Hong 1 satellite into orbit. China’s Long March 1 came from the Dong Feng 3 ballistic missile. Israel’s Shavit was based on the Jericho II ballistic missile. The Shavit launched in Ofek-1 satellite in 1988. The exception to this trend was Japan, which launched its first satellite into orbit, Ohsumi, in 1970 on an L-4S rocket. The L-4S was based on the 23-centimeter- (9.1-inch-) long Pencil sounding rocket, developed by a group led by Hideo Itokawa, then a professor of engineering at the University of Tokyo’s Institute of Industrial Science. It did not have a military origin. Japan was disarmed and its aerospace industry was dismantled as a condition of its surrender to the Allies after World War II.

The Soviet Union’s space program also underwent a tough maturation process with delays, failures and cancellations. Internal politics were partially to blame for a series of political and technical problems. Most national space programs, including the United States’ NASA, are directed by a central agency. The Soviet space program was run by competing agencies, called design bureaus.

Chief rocket designer Sergei Korolëv depended on cooperation from other design bureau chiefs to complete his rockets. This was especially true of propulsion system chief Valentin Glushko. Glushko had been a friend of Korolëv’s who became a professional rival. In 1960 and 1961, Glushko was planning to design a new rocket engine that used propellant fuel, which is better suited for ICBMs, not cryogenic fuel, which is better suited for the massive lift needed for moon missions.

In 1962, the N-1 rocket design configuration Korolëv supported was approved. He had successfully worked with a design bureau competing against the design bureau Glushko headed. In August 1964, the Soviet government approved a crewed mission to the moon. That delay doomed the Soviet Union’s intention to beat the U.S. to the moon. By then, Apollo had been a priority for the U.S. government for two years. NASA expanded its infrastructure, adding new branches and buildings, including rocket assembly and launch capabilities. After the development of the N-1 rocket failed, the Soviet Union abandoned planned crewed missions to the moon and Mars, altogether.

Since the turn of the new millennium, a new space power has risen. In 2003, China joined Russia and the United States as the only other nation to have an independent, crewed spaceflight program when it launched three taikonauts into orbit on the Shenzhou 5 in 2003. Chinese achievement did not stop there. China has also found success completing space stations. When China completed the Tiangong-3 space station in late 2022, it became the second nation to build and orbit a multipart space station by itself, after Russia with Mir, the first modular space station assembled in orbit. The test space stations, Tiangong-1 and Tiangong-2, were launched in 2011 and 2016, respectively. They were then deorbited in 2018 and 2019, respectively.

The U.S.S.R. launched the first space station with Salyut I in 1971. Tragically, that crew died on re-entry when their Soyuz 11 depressurized unexpectedly. At the time, cosmonauts did not wear spacesuits, which would have protected them from depressurization, on re-entry. The Salyut space stations, seven in total, gave way to the multipart Mir. The main module was orbited in 1986. The space station was completed in 1996 and deorbited in 2001. The U.S. launched its own space station, Skylab, in 1973. Skylab received its third, and final, crew in 1974. In 1979, the space station re-entered Earth’s atmosphere and fell into the Indian Ocean, after receiving three crews, in 1979.

Space stations marked the most visible part of international cooperation. Before the end of the Apollo era, came the beginnings of cooperation between the Soviet and U.S. space programs. In 1975 — in the midst of the Cold War — a NASA Apollo spacecraft docked with a Soviet Soyuz and spent two days in orbit together in July. The superpowers cooperated again when the U.S. space shuttle carried out a series of missions with Russia’s Mir, docking nine times. The U.S. space shuttle could dock with Russia’s Mir because it was designed to do so after the Soviet spy agency, the KGB, stole the space shuttle’s design plans.

The International Space Station (ISS), which launched in 1998, has broadened international cooperation to include the European Union, Japan and Canada as fellow partners. Facilities dedicated to space station manufacturing, training, testing and launching are spread throughout the partner nation locations. Many countries, including nonpartner nations, conduct research on the International Space Station. Nonpartner nations who have sent people to the ISS include South Africa, the United Arab Emirates, South Korea, Malaysia, Israel, Türkiye, Brazil, Kazakhstan and Belarus.

Russia started transporting astronauts from the U.S. and other partner nations to and from the ISS after the shuttle was retired in 2011. A private company is also sending humans into low-Earth orbit now. Space Exploration Technologies (SpaceX) began sending astronauts to the ISS on its Crew Dragon spacecraft on its Falcon rocket in 2020. SpaceX, Boeing and Blue Origin are just some of the companies that have received subsidies from the U.S. government to further their programs.

Corporations have always been involved in the U.S. space program. Formerly, they got designs from NASA, and then built the machines and handed them back over to NASA to operate. What differs is that companies are contracted to complete all those steps with less government oversight and support.

This became possible because components and systems became less expensive and more accessible. But unlike governments, companies are more responsible to their shareholders than the public. Also different from governments there is less trust, less transparency and less accountability.

Space programs are not satisfied with remaining in low-Earth orbit. The U.S. plans to return sending humans to the moon with NASA’s Artemis program. The Artemis rocket performed a successful uncrewed test flight around the moon in late 2022. After a crewed lunar flyby with an Orion spacecraft and a crewed moon landing in the mid 2020s, the plan is to establish a lunar base. The U.S. is not alone in these ambitions. China plans to send a crewed mission to the moon by 2030 on the planned Long March 10 rocket. Both nations also plan to send crewed missions to Mars in the future, also.