How NASA Works

By: Craig Freudenrich, Ph.D. & Patrick J. Kiger  | 
Space Shuttle
Billows of smoke and steam infused with the fiery light from space shuttle Endeavour's launch fill NASA Kennedy Space Center's Launch Pad 39A. Endeavour lifted off on the mission's sixth launch attempt, on July 15, 2009. NASA/Sandra Joseph, Kevin O'Connell

Back in 1958, Americans were worried that the Soviet Union, which had launched the Sputnik satellite into orbit the previous year, would attain superiority over the U.S. in the then-unfamiliar realm of outer space. As U.S. senator and future President Lyndon Johnson proclaimed, "Control of space means control of the world" [source: Wasser].

The U.S. Army and the Air Force, which both had experience with missiles, were eager to take on the challenge. But in the end, Congress and President Dwight D. Eisenhower decided to create an entirely new civilian agency — one that would take the lead in everything from developing spacecraft capable of transporting humans into space to studying Earth's own atmosphere from above.


In the spring of that year, President Eisenhower sent draft legislation to Congress to establish a new organization, the National Aeronautics and Space Agency. But at the urging of a Congressional aide named Eilene Galloway, the name in the bill was changed to the National Aeronautics and Space Administration (NASA). That meant that the organization's head would hold the title of administrator, which sounded more powerful. After Congress passed the legislation, it was signed into law by Eisenhower. On Oct. 1, 1958, NASA — with administrator T. Keith Glennan at the helm — opened for business [source: Dick].

In the six decades since that day, NASA has become one of the most admired and celebrated parts of the U.S. government. In the popular imagination, NASA is a brain trust of elite scientists and engineers who create spacecraft capable of exploring the cosmos, along with a corps of highly trained astronauts who embody the American virtues of bravery and resourcefulness.

And to be sure, NASA's accomplishments live up to the hype. In addition to putting humans on the moon and establishing the International Space Station in Earth's orbit, NASA has sent robotic probes to other planets in our solar system, and helped astronomers gaze into the depths of the universe. Beyond all that, NASA also has used its satellites and scientists to help us to better understand our own planet, and done vital work in studying climate change.

In the process, NASA also has also been dealt catastrophic setbacks, including the loss of several spacecraft and their crews in accidents, as well as controversies over its performance and direction. And since the end of its space shuttle program, NASA has had to turn increasingly to the growing private space launch sector to help it achieve its mission.

In this article, we'll look at NASA's history and accomplishments, and how it goes about the job of space exploration.

Who Decides What NASA Does?

JFK, John Glenn, Alan Shepherd
President John F. Kennedy makes his first visit to Cape Canaveral. Also pictured are astronauts John Glenn, Jr. (partially obscured); Christopher Kraft, Jr., and Alan Shepard, Jr. (right), who made the U.S.'s first manned space flight in 1961. NASA

NASA is an independent civilian space agency under the executive branch, created by Congress to help execute policy or provide special services (other independent agencies include the Central Intelligence Agency, the Environmental Protection Agency and the National Science Foundation). Although NASA is not a cabinet-level organization like the Department of Defense, its administrator gets nominated by the president and must be confirmed by the Senate.

NASA's agenda often has been set by U.S. presidents. In 1961, for example, President John F. Kennedy decided to focus NASA's goal on putting humans on the moon within a decade — a goal that the agency achieved with a year to spare. In 1972, President Richard M. Nixon directed NASA to develop the space shuttle program [source: Garber].


In 1984, President Ronald Reagan called on NASA to develop a space station within a decade [source: Rossiter]. His successor, George H.W. Bush, in 1989 proposed sending humans to Mars [source: Weinraub]. President George W. Bush in the 2000s launched the Constellation program, which aimed to develop a new space vehicle and return to the moon by 2020, a project envisioned as a prelude to a future Mars mission [source: Wall].

Presidents also have undone their predecessors' plans. President Barack Obama in 2010 cancelled Constellation, after a presidential commission concluded that it was too far behind schedule and cost too much. Obama decided to abandon the moon return and instead send astronauts to a near-Earth asteroid by 2025, and then to Mars in the mid-2030s. To that end, NASA continued to work on a manned spacecraft, Orion, that had been part of the Constellation program, as well as a massive, powerful rocket, the Space Launch System, or SLS. A robotic version of Orion was launched into space in 2014 [source: Wall].

Under Obama's successor, Donald Trump, the moon return is again on the agenda, and NASA is contemplating selling naming rights to space missions to companies. Trump also wants to end direct federal support of the International Space Station (ISS) by 2025 in hopes that private space companies will take over [source: Dean]. Space, it seems, is ripe for commercialization.

How Is NASA Organized?

Richard Jones
Flight director Richard Jones was the first Hispanic to lead space shuttle teams. NASA

When you think of NASA, you likely think of the astronauts, but there's a lot of other personnel at the organization. Accomplishing NASA's mission requires people to develop and build new technologies, assemble and test spacecraft and their components, train astronauts and pilots, and provide mission support services. The organization also funds research by thousands of scientists across the nation.

Doing all that is expensive and complicated. NASA's budget in fiscal 2018 was $20.7 billion, up $1.1 billion from the previous year [source: Wall]. The organization has a staff of 17,400 employees, distributed among 17 NASA centers and facilities across the U.S., plus another 60,000 contractors whose work supports them [source: NASA].


NASA's internal structure has evolved over the years, but as of 2018, it was organized into directorates, located at NASA headquarters in Washington, D.C., that handle various parts of its mission.

  • The Science Mission Directorate (SMD) focuses on increasing scientific knowledge of the solar system, the reaches of space and time, and Earth itself. It uses a variety of tools, from robotic orbital observatories to ground-based instruments.
  • The Human Exploration and Operations Mission Directorate (HEOMD) researches and develops technology to enable humans to live and work in space and also manages space communication and navigation services.
  • The Space Technology Mission Directorate (STMD) develops the technology needed for space exploration and other space missions.
  • The Mission Support Directorate (MSD) improves institutional processes for space missions, to make them safer and more efficient.
  • The Aeronautics Research Mission Directorate (ARMD) works on transforming terrestrial aviation, by improving aircraft and operations efficiency and safety, and also works to reduce the environmental impact of flight.
  • The Administrator's Staff Offices is the top layer of leadership at NASA, which oversees everything from safety on space missions to managing the workforce to coordinating with other nations in space partnerships.
  • The Office of Inspector General (OIG) is the official watchdog that keeps an eye on the agency and how it spends taxpayer dollars [source: NASA].

NASA Centers

Mae Jemison
An onboard photo of astronaut Mae Jemison working aboard the space shuttle Endeavour in 1992. Jemison was the first African-American woman in space. NASA

NASA has 10 major centers that do R&D and stage its missions. Here's what they do [sources: NASA, NASA]:

  • Kennedy Space Center (KSC), located in Cape Canaveral, Florida, is NASA's most famous facility. It launched the first U.S. astronauts into space and helped put humans on the moon. Today, it's the home of NASA's Launch Services Program, which works with private sector space launch companies like SpaceX and Boeing to put satellites and space telescopes into orbit. It also leads research on the growing of plants in microgravity environments.
  • Johnson Space Center (JSC), located in Houston, became famous as the center for mission control for U.S. manned space flights. (Remember the movie line, "Houston, we have a problem"?). Today, it continues to manage the International Space Station (ISS), and operates NASA's Human Research Program on the ISS, which aims to protect the health and safety of astronauts. JSC also amasses info on orbital debris and analyzes its risk to spacecraft.
  • Goddard Space Flight Center (GSFC), located in Prince Georges County, Maryland, works with other centers and university researchers to conceptualize, design, test, build, integrate and operate spacecraft, instruments, and space, airborne and ground missions. Goddard's scientists help to figure out the science requirements for each mission, and then processes and analyzes the data to help further our understanding of Earth, the solar system and the universe.
  • Armstrong Flight Research Center (AFRC), located in Edwards, California, provides specialized aircraft to observe Earth's physical processes, tests new technologies for observation, and calibrates and validates satellites. As part of that work, it maintains NASA's Stratospheric Observatory for Infrared Astronomy (SOFIA), the world's biggest airborne observatory.
  • Ames Research Center (ARC), located at Moffett Field, California,conducts research in aeronautics, astrobiology, astrophysics, and the planetary, biological and Earth sciences, and is home to the Mars Climate Modeling Center. It also operates the Kepler space telescope.
  • Glenn Research Center (GRC), located in Cleveland, Ohio, develops electric propulsion systems for science missions, and develops and tests electronics for use in extreme environments, such as the surface of Venus.
  • Jet Propulsion Laboratory (JPL), located in Pasadena, California, develops and operates robotic space missions. It's involved in transmitting data back from NASA probes to scientists and the public back on Earth via the Deep Space Network (DSN).
  • Langley Research Center (LaRC), located in Hampton, Virginia, works to develop remote sensing technologies for better-quality atmospheric data, and studies air quality, radiation, climate and the composition of the atmosphere. The hit book and movie "Hidden Figures" spotlighted LaRC.
  • Marshall Space Flight Center (MSFC), located in Huntsville, Alabama, specializes in developing scientific missions, instruments such as the Imagine X-ray Polarimeter Explorer, and software applications that use data collected from the vantage point of space to study Earth, the solar system, and the rest of the universe. One of the center's specialties is developing applications that use data from space-based instruments that observe Earth.
  • Stennis Space Center (SSC), in Hancock County, Mississippi, is working to develop propulsion elements such as the RS-25 engine, core stage, and exploration upper stage for the Space Launch System (SLS), the heavy launch vehicle that NASA will use for future manned missions to the moon and Mars, as well as robotic missions to the outer planets.

Next, let's look at what NASA has accomplished since its inception.


NASA Satellites

In the shadow of Saturn, unexpected wonders appear. The robotic Cassini spacecraft drifted into Saturn giant planet's shadow for about 12 hours and looked back toward the eclipsed Sun. Visible in spectacular detail is Saturn's E ring and the outermost ring visible above. NASA

The U.S. actually began launching satellites shortly before NASA was created. On Jan. 1, 1958, a Juno 1 rocket launched from Cape Canaveral Air Force Station in Florida successfully and rose 200 miles (321 kilometers) into the sky before releasing a satellite called Explorer 1 [source: NASA]. But Explorer wasn't just about getting into orbit — the satellite produced important scientific knowledge as well, by documenting the existence of the Van Allen Radiation Belt that encircles the Earth [source: Garber and Launius].

In the decades that followed, Explorer was followed by numerous other unmanned missions. NASA has sent several robotic space probes to various places in the solar system. The early probes (Ranger, Lunar Orbiter, Pioneer and Surveyor) were sent to the moon to obtain information necessary for the moon landings of the Apollo program. NASA later returned to the moon with the Clementine (1992) and Lunar Prospector (1998) probes for further exploration.


NASA has sent flybys, orbiters and landers to explore the inner and outer planets. They include:

  • Mariner: flybys of Mercury, Venus and Mars
  • Pioneer: flybys of the moon (early missions), Jupiter (Pioneer 10), Venus (Pioneer Venus missions)
  • Voyager: flybys of Jupiter, Saturn, Uranus and Neptune
  • Magellan: Venus orbiter and radar mapping
  • Viking: Mars landings
  • Galileo: Jupiter orbiter
  • Hubble Space Telescope: an orbital observatory that has helped scientists to peer into the early universe and more precisely estimate its age.
  • Cassini: Saturn orbiter with Huygens landing probe on Saturn's moon, Titan
  • NEAR: asteroid orbiter
  • Deep Space 1: asteroid flyby
  • Stardust: comet flyby and sample return
  • Pathfinder, Spirit, Opportunity: Mars landing rovers
  • Mars Climate Orbiter: Mars orbiter
  • Messenger: Mercury orbiter
  • Dawn: first probe to orbit an object in the main asteroid belt between Mars and Jupiter [source: JPL].
  • WISE/NEOWISE: scanned the entire celestial sky in infrared 1.5 times, and captured more than 2.7 million images of objects in space, from comets to galaxies [source: NASA].
  • Juno: a Jupiter orbiter that revealed the turbulent nature of the solar system's biggest planet [source: NASA].
  • Curiosity and Opportunity: two rovers that are exploring the surface of Mars [source: Koren].
  • New Horizons: transmitted color images of the dwarf planet Pluto and its Charon [source: NASA].
  • InSight: launched in May 2018, this probe will investigate the dynamics of Martian tectonic activity [source: NASA].

These probes have made many invaluable scientific discoveries. Next, we'll look at Projects Mercury, Gemini and Apollo.

Projects Mercury, Gemini and Apollo

Buzz ALdrin, moon
Astronaut Buzz Aldrin poses for a photograph beside the United States flag during the Apollo 11 Extravehicular Activity (EVA) landing on the moon, 1969. This was the world's first landing on the moon. NASA

Project Mercury(1961 to 1963)

The goal of Project Mercury was to determine whether humans could survive in space. Single astronauts were launched into space in the Mercury spacecraft on six missions and spent up to 34 hours in space.

Soon after, astronaut Alan B. Shepard became the first American in space when he completed a 15-minute suborbital flight. President Kennedy committed NASA to sending a man to the moon and back before the end of the '60s. Under the direction of then-Vice President (later President) Lyndon B. Johnson, Congress appropriated funds and NASA expanded its programs to achieve President Kennedy's vision [source: Garber and Launius].


Project Gemini (1965-1966)

The Gemini spacecraft carried two astronauts and could maneuver in space. Over the course of 10 missions, astronauts changed orbits, rendezvoused with other spacecraft, docked with an unmanned Agena rocket, and walked and spent long periods of time in space.

Upon completion of the Gemini program, NASA learned how to fly, live and work in space for the durations of around two weeks that were necessary to send men to the moon and back [source: Garber and Launius].

Project Apollo (1967-1972)

Apollo's primary mission was to land men on the moon, explore it and return them safely to Earth. The Apollo spacecraft carried three men and consisted of a command module (crew quarters), service module (rocket motor, fuel cells, fuel tank, maneuvering rockets, science packages and life support), and a lunar module (a two-man, two-stage independent space vehicle for landing and lifting off from the lunar surface).

The Apollo 1 mission ended with a tragic fire on the launchpad that claimed the lives of three astronauts, Virgil Grissom, Edward White and Roger Chaffee. The Apollo spacecraft was redesigned and tested in Earth orbit during Apollo 7. Apollo 8 took astronauts into lunar orbit, then Apollo missions 9 and 10 tested the lunar module in earth orbit and lunar orbit, respectively. Apollo 11 carried the first men (Neil Armstrong and Edwin "Buzz" Aldrin) to the lunar surface, while a third astronaut (Michael Collins) orbited the moon in the command module. Armstrong and Aldrin spent hours walking on the moon, and their mission fulfilled President Kennedy's challenge.

NASA sent six more missions to explore various places on the moon, where astronauts spent up to two days exploring the lunar surface and gathering samples of moon rocks. One mission, Apollo 13, did not make it to the moon because an explosion crippled the spacecraft along the route. NASA showed its ability to handle a crisis as the agency improvised solutions to get the spacecraft around the moon and return the crew safely to Earth [source: Garber and Launius].

Skylab to the International Space Station

Jack Lousma, Skylab pilot, taking bath
Astronaut Jack R. Lousma, Skylab 3 pilot takes a hot bath in the crew quarters of the Orbital Workshop (OWS) of the Skylab space station cluster in Earth Orbit in 1973. NASA

In 1973, NASA placed its first space station, Skylab, into Earth orbit. Although Skylab was damaged in flight, NASA sent the first crew to repair the spacecraft and make it livable, which showed repairs could be achieved in space. The crew remained on board for 28 days and conducted numerous experiments on the physiological effects of long duration spaceflight and observations of the sun and Earth. Two subsequent crews spent time (58 days and 84 days) in the Skylab continuing experiments and observations, demonstrating that humans could stay in space for long periods [source: Garber and Launius].

Apollo Soyuz Test Project (1975)

The final Apollo mission was the Apollo Soyuz Test project, which was a joint mission with the Soviet Union. An Apollo spacecraft with three astronauts docked in Earth orbit with a Russian Soyuz spacecraft containing two cosmonauts. The crews spent two days together conducting experiments. The flight demonstrated that the United States and the Soviet Union could work together in space and laid the groundwork for the Shuttle/Mir program and the International Space Station two decades later [source: Howell].


Space Shuttle (1981-2011)

In 1981, the first reusable spacecraft, the space shuttle, flew into Earth's orbit. NASA's fleet of four space shuttles operated for 30 years, ferrying humans into space, deploying satellites and space probes, and helping to build the International Space Station. Two shuttles and their crews, the Challenger and the Columbia were tragically lost in 1986 and 2003, respectively. NASA learned many lessons in operating the shuttle and made several redesigns and procedural changes to make the shuttle flights safer. The 135th and final shuttle mission concluded on July 21, 2011, when the shuttle Atlantis rolled to a stop at Kennedy Space Center in Florida [source: Loff].

International Space Station (1998-Present)

NASA, working with 15 other nations, began building the ISS in 1998, with the goal of establishing a permanent human presence in Earth orbit for conducting experiments and observations The largest single structure ever built by humans outside of Earth, the International Space Station has been continuously occupied since November 2000, though construction continued until 2011. Some 230 people from 18 countries have sent time at the ISS [source: Howell].

Criticisms of NASA

Star Trek cast
The Shuttle Enterprise rolls out of the Palmdale manufacturing facilities with 'Star Trek' cast members in 1976. They are (L-R): NASA Administrator Dr. James D. Fletcher, DeForest Kelley, George Takei, James Doohan, Nichelle Nichols, Leonard Nimoy, Gene Rodenberry (producer), and Walter Koenig. NASA

No one can deny that NASA has achieved extraordinary things in its relatively short lifetime. However, NASA is not without its critics. Criticisms seem to come on two fronts:

  • Is the high cost of space exploration worth the scientific/economic returns? Scientific and technological advancements cannot always come with a price tag, but rather are invaluable to humanity. Well-known products or technologies like memory foam, scratch-resistant eyeglasses, LASIK and space blankets all came courtesy of NASA inventions.
  • Is it worth risking human lives to explore space when expendable robots can do it at a cheaper price in both dollars and human risk? This question has been bandied about since the inception of NASA and there is no definitive answer. Many people feel that the human experience of space exploration is as important and priceless as the mere data that a robot would send back. For example, a geologist on the moon would know more about what rocks to look for and return than a robot.
  • Are we taking unnecessary risks in space exploration? Space is a hostile environment and space exploration will always have dangers. However, NASA tries to minimize risks where possible and make it as safe as it can.


What is NASA's Future?

Crew Dragon, Space X
A reporter photographs a mockup of the Crew Dragon at the SpaceX rocket factory in Hawthorne, Calif., 2018. SpaceX plans to use the spacecraft to carry NASA astronauts to the ISS for the first time since the space shuttle program was retired in 2011. David McNew/Getty Images

During his first term in the early 2000s, President George W. Bush laid out an ambitious plan for NASA's future. He planned to replace the aging space shuttles with a new program, Constellation, that NASA administrator Michael Griffin described as "Apollo on steroids." Bush aimed to have U.S. astronauts return to the moon in the 2020s [source: Lewis].

But after Barack Obama took office in 2009, he pointed NASA in a different direction. After a commission of experts found that the Constellation program was behind schedule and exceeding its budget, Obama decided to cancel the program, and abandon the planned moon visits. Instead, he wanted the agency to aim for even more ambitious goals of landing astronauts on a near-Earth asteroid by 2025, and reaching Mars in the 2030s. To that end, NASA embarked upon a new plan to develop the Orion crew capsule, a portion of Constellation that was kept, and to develop a massive new rocket called the Space Launch System (SLS) [sources: Lewis, Wall].


The end of the shuttle program in 2011 put NASA in a bind, because it didn't yet have a manned spacecraft program to replace it. U.S. astronauts were compelled to hitch rides on Russian spacecraft at more than $80 million per seat [source: Warner]. But private sector companies soon stepped in to fill some of the gap left by the shuttle program's demise. In 2012, a robotic SpaceX Dragon became the first commercial spacecraft to fly a cargo mission to the ISS [source: Howell].

The privatization of space travel that began under Obama seems likely to continue under President Donald Trump, in part because the cost of launching a commercial robotic vehicle into orbit is about a fifth of the $1 billion that a shuttle launch cost [source: Mack]. Private space companies SpaceX and Boeing are planning to fly NASA astronauts to the ISS in 2019, in what will be the first manned launches from U.S. soil since the shuttle program's conclusion [source: Reints]. That could signal the start of a new era for NASA, in which it relies on commercial space companies for routine missions and conserves its resources for the biggest, most adventurous quests.

At a 2018 gathering of present and past NASA officials, Trump administration NASA administrator Jim Bridenstine pledged that the agency that first reached the moon would continue to push the envelope in the 21st century by returning to the moon and aiming for Mars.

"A lot of us were not even born when all of that [Apollo] took place, and the visions that have come since then have not always materialized," Bridenstine said. "But because those visions existed, we at this point in history have more opportunity to do more than ever before, " [source: Dean].

Originally Published: Oct 16, 2018

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