The Space Shuttle program was the fourth human spaceflight program carried out by the U.S. National Aeronautics and Space Administration (NASA), which accomplished routine transportation for Earth-to-orbit crew and cargo from 1981 to 2011. Its official name, Space Transportation System (STS), was taken from a 1969 plan for a system of reusable spacecraft of which it was the only item funded for development. It flew 135 missions and carried 355 astronauts from 16 countries, many on multiple trips.
Human spaceflight programs have been conducted, started, or planned by multiple countries and companies. The age of manned rocket flight was initiated by Fritz von Opel who piloted the world's first rocket-propelled flight on 30 September 1929. All space flights depend on rocket technology; von Opel was the co-designer and financier of the visionary project. Until the 21st century, human spaceflight programs were sponsored exclusively by governments, through either the military or civilian space agencies. With the launch of the privately funded SpaceShipOne in 2004, a new category of human spaceflight programs – commercial human spaceflight – arrived. By the end of 2022, three countries and one private company (SpaceX) had successfully launched humans to Earth orbit, and two private companies had launched humans on a suborbital trajectory.
The Constellation program was a crewed spaceflight program developed by NASA, the space agency of the United States, from 2005 to 2009. The major goals of the program were "completion of the International Space Station" and a "return to the Moon no later than 2020" with a crewed flight to the planet Mars as the ultimate goal. The program's logo reflected the three stages of the program: the Earth (ISS), the Moon, and finally Mars—while the Mars goal also found expression in the name given to the program's booster rockets: Ares. The technological aims of the program included the regaining of significant astronaut experience beyond low Earth orbit and the development of technologies necessary to enable sustained human presence on other planetary bodies.
Private spaceflight refers to spaceflight developments that are not conducted by a government agency, such as NASA or ESA.
Shuttle-derived vehicles (SDV) are space launch vehicles and spacecraft that use components, technology, and infrastructure originally developed for the Space Shuttle program.
The Exploration Systems Architecture Study (ESAS) is the official title of a large-scale, system level study released by the National Aeronautics and Space Administration (NASA) in November 2005 of his goal of returning astronauts to the Moon and eventually Mars—known as the Vision for Space Exploration. The Constellation Program was cancelled in 2010 by the Obama Administration and replaced with the Space Launch System, later renamed as the Artemis Program in 2017 under the Trump Administration.
American private space transportation company SpaceX has developed and produced several spacecraft named Dragon. The first family member, now referred to as Dragon 1, flew 23 cargo missions to the ISS between 2010 and 2020 before retiring. With this first version not designed for carrying astronauts, it was funded by NASA with $396 million awarded through the Commercial Orbital Transportation Services (COTS) program, with SpaceX being announced as a winner of the first round of funding on August 18, 2006.
The Ares V was the planned cargo launch component of the cancelled NASA Constellation program, which was to have replaced the Space Shuttle after its retirement in 2011. Ares V was also planned to carry supplies for a human presence on Mars. Ares V and the smaller Ares I were named after Ares, the Greek god of war.
Ares I was the crew launch vehicle that was being developed by NASA as part of the Constellation program. The name "Ares" refers to the Greek deity Ares, who is identified with the Roman god Mars. Ares I was originally known as the "Crew Launch Vehicle" (CLV).
The Crew Exploration Vehicle (CEV) was a component of the U.S. NASA Vision for Space Exploration plan. A competition was held to design a spacecraft that could carry humans to the destinations envisioned by the plan. The winning design was the Orion spacecraft.
NASA proposed several concept moonbases for achieving a permanent presence of humans on the Moon since the late 1950s. Research and exploration of the Moon has been a large focus of the organization since the Apollo program. NASA's peak budget was in 1964-1965, when it comprised 4% of all federal spending in service of the Apollo Moon landing project. Though lunar landings ever since the conclusion of the Apollo program in 1972 have ceased, interest in establishing a permanent habitation on the lunar surface or beyond low Earth orbit has remained steady. Recently, renewed interest in lunar landing has led to increased funding and project planning. NASA requested an increase in the 2020 budget of $1.6 billion, in order to make another crewed mission to the Moon under the Artemis program by 2025, followed by a sustained presence on the Moon by 2028. A crew was selected for the planned crewed mission, Artemis II, in April of 2023.
Space architecture is the theory and practice of designing and building inhabited environments in outer space. This mission statement for space architecture was developed at the World Space Congress in Houston in 2002 by members of the Technical Aerospace Architecture Subcommittee of the American Institute of Aeronautics and Astronautics (AIAA). The architectural approach to spacecraft design addresses the total built environment. It is mainly based on the field of engineering, but also involves diverse disciplines such as physiology, psychology, and sociology.
The Shuttle-Derived Heavy Lift Launch Vehicle ("HLV") was an alternate super heavy-lift launch vehicle proposal for the NASA Constellation program. It was first presented to the Augustine Commission on 17 June 2009.
DIRECT was a late-2000s proposed alternative super heavy lift launch vehicle architecture supporting NASA's Vision for Space Exploration that would replace the space agency's planned Ares I and Ares V rockets with a family of Shuttle-Derived Launch Vehicles named "Jupiter". It was intended to be the alternative to the Ares I and Ares V rockets which were under development for the Constellation program, intended to develop the Orion spacecraft for use in Earth orbit, the Moon, and Mars.
A space tug is a type of spacecraft used to transfer spaceborne cargo from one orbit to another orbit with different energy characteristics. The term can include expendable upper stages or spacecraft that are not necessarily a part of their launch vehicle. However, it can also refer to a spacecraft that transports payload already in space to another location in outer space, such as in the Space Transportation System concept. An example would be moving a spacecraft from a low Earth orbit (LEO) to a higher-energy orbit like a geostationary transfer orbit, a lunar transfer, or an escape trajectory.
The Artemis program is a robotic and human Moon exploration program led by the United States' National Aeronautics and Space Administration (NASA) along with six major partner agencies— the European Space Agency (ESA), the German Aerospace Center (DLR), the Japan Aerospace Exploration Agency (JAXA), the Canadian Space Agency (CSA), the Israel Space Agency (ISA), and the Italian Space Agency (ASI). The Artemis program is intended to reestablish a human presence on the Moon for the first time since the Apollo 17 mission in 1972. The main parts of the program are the Space Launch System (SLS), the Orion spacecraft, the Lunar Gateway space station, and the commercial Human Landing Systems. The program's long-term goal is to establish a permanent base on the Moon to facilitate the feasibility of human missions to Mars.
The International Lunar Resources Exploration Concept (ILREC) was a proposed mission architecture under President George H. W. Bush's Space Exploration Initiative (SEI) by Kent Joosten, an engineer at Johnson Space Center. The plan would have used the help of international partners, mainly the Soviet Union, to assemble a lunar base and sustainable lunar transportation service.
First Lunar Outpost was a proposal for a crewed lunar mission that would have launched sometime in the 2010s. It was part of George H. W. Bush's Space Exploration Initiative. The main purpose of the proposal was to offer a much cheaper alternative to NASA's 90-day study from 1989 by a factor of US$30 billion. Although it did not gather much mainstream attention, NASA dedicated much time to assembling a very detailed and thorough proposal. However, the entire Space Exploration Initiative was cancelled soon after the proposal's completion, and NASA had to close the Office of Space Exploration in March 1993.
The Gateway Logistics Services will be a series of uncrewed spaceflights to the Lunar Gateway space station, with the purpose of providing logistical services to the Gateway. Overseen by NASA's Gateway Logistics Element, the flights will be operated by commercial providers, contracted by the agency in support of crewed expeditions to the Gateway made under the Artemis program. As of March 2023, SpaceX is the only company contracted to provide the services.
