The Space Shuttle is a retired,partially reusable low Earth orbital spacecraft system operated from 1981 to 2011 by the U.S. National Aeronautics and Space Administration (NASA) as part of the Space Shuttle program. Its official program name was Space Transportation System (STS),taken from the 1969 plan led by U.S. Vice President Spiro Agnew for a system of reusable spacecraft where it was the only item funded for development.
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 program name was Space Transportation System (STS),taken from a 1969 plan for a system of reusable spacecraft where it was the only item funded for development,as a proposed nuclear shuttle in the plan was cancelled in 1972. It flew 135 missions and carried 355 astronauts from 16 countries,many on multiple trips.
Marshall Space Flight Center,located in Redstone Arsenal,Alabama,is the U.S. government's civilian rocketry and spacecraft propulsion research center. As the largest NASA center,MSFC's first mission was developing the Saturn launch vehicles for the Apollo program. Marshall has been the lead center for the Space Shuttle main propulsion and external tank;payloads and related crew training;International Space Station (ISS) design and assembly;computers,networks,and information management;and the Space Launch System. Located on the Redstone Arsenal near Huntsville,MSFC is named in honor of General of the Army George C. Marshall.
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.
The Space Shuttle Solid Rocket Booster (SRB) was the first solid-propellant rocket to be used for primary propulsion on a vehicle used for human spaceflight. A pair of them provided 85% of the Space Shuttle's thrust at liftoff and for the first two minutes of ascent. After burnout,they were jettisoned,and parachuted into the Atlantic Ocean,where they were recovered,examined,refurbished,and reused.
The Space Shuttle external tank (ET) was the component of the Space Shuttle launch vehicle that contained the liquid hydrogen fuel and liquid oxygen oxidizer. During lift-off and ascent it supplied the fuel and oxidizer under pressure to the three RS-25 main engines in the orbiter. The ET was jettisoned just over 10 seconds after main engine cut-off (MECO) and it re-entered the Earth's atmosphere. Unlike the Solid Rocket Boosters,external tanks were not re-used. They broke up before impact in the Indian Ocean,away from shipping lanes and were not recovered.
Earth orbit rendezvous (EOR) is a method for conducting round trip human flights to the Moon,involving the use of space rendezvous to assemble,and possibly fuel,components of a translunar vehicle in low Earth orbit. It was considered as an alternative to direct ascent but ultimately rejected in favor of lunar orbit rendezvous (LOR) for NASA's Apollo program of the 1960s and 1970s,mainly because LOR does not require a spacecraft big enough to both make the return trip from Earth orbit to splash down in the ocean,and a soft landing on the lunar surface. The two main proposed methodologies were:the in-space assembly of fueled spacecraft modules via docking techniques;and the in-space refueling of fully assembled spacecraft. This was the preferred approach adopted by the Soviet Union for achieving human lunar missions.
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.
The Altair spacecraft,previously known as the Lunar Surface Access Module or LSAM,was the planned lander spacecraft component of NASA's cancelled Constellation program. Astronauts would have used the spacecraft for landings on the Moon,which was intended to begin around 2019. The Altair spacecraft was planned to be used both for lunar sortie and lunar outpost missions.
The Earth Departure Stage (EDS) is the name given to the proposed second stage of the Block 2 Space Launch System. The EDS is intended to boost the rocket's payload into a parking orbit around the Earth and from there send the payload out of low Earth orbit to its destination in a manner similar to that of the S-IVB rocket stage used on the Saturn V rockets that propelled the Apollo spacecraft to the Moon. Its development has been put on hold until stages capable of transferring heavy payloads to Mars are required.
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 Saturn V is a retired American super heavy-lift launch vehicle developed by NASA under the Apollo program for human exploration of the Moon. The rocket was human-rated,had three stages,and was powered by liquid fuel. Flown from 1967 to 1973,it was used for nine crewed flights to the Moon,and to launch Skylab,the first American space station.
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.
The space policy of the Barack Obama administration was announced by U.S. President Barack Obama on April 15,2010,at a major space policy speech at Kennedy Space Center. He committed to increasing NASA funding by $6 billion over five years and completing the design of a new heavy-lift launch vehicle by 2015 and to begin construction thereafter. He also predicted a U.S.-crewed orbital Mars mission by the mid-2030s,preceded by the Asteroid Redirect Mission by 2025. In response to concerns over job losses,Obama promised a $40 million effort to help Space Coast workers affected by the cancellation of the Space Shuttle program and Constellation program.
The retirement of NASA's Space Shuttle fleet took place from March to July 2011. Discovery was the first of the three active Space Shuttles to be retired,completing its final mission on March 9,2011;Endeavour did so on June 1. The final shuttle mission was completed with the landing of Atlantis on July 21,2011,closing the 30-year Space Shuttle program.
Liberty was a 2011 launch vehicle concept proposed by ATK and Airbus Defence and Space for phase 2 of the NASA Commercial Crew Development (CCDev) program intended to stimulate development of privately operated crew vehicles to low Earth orbit.
During the lifetime of the Space Shuttle,Rockwell International and many other organizations studied various Space Shuttle designs. These involved different ways of increasing cargo and crew capacity,as well as investigating further reusability. A large focus of these designs were related to developing new shuttle boosters and improvements to the central tank,but also looked to expand NASA's ability to launch deep space missions and build modular space stations. Many of these concepts and studies would shape the concepts and programs of the 2000s such as the Constellation,Orbital Space Plane Program,and Artemis program.
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 less expensive 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 detailed and thorough proposal. However,the entire Space Exploration Initiative was cancelled soon after the proposal's completion,and NASA closed the Office of Space Exploration in March 1993.
