The space shuttle is a rocket-powered transport that takes astronauts into space orbit and brings them back to Earth. It was developed by the U.S. National Aeronautics and Space Administration (NASA). As per NASA’s official website, it made 135 journeys between 1981 and 2011.
When it comes to capacity, the space shuttle could carry a maximum of 7 astronauts on board. Besides astronauts, it has taken artificial satellites to their destinations as well. This transport was also instrumental in the construction of the International Space Station (ISS) as it carried the parts needed to build the same. Each space shuttle journey, called a “mission,” lasted for 1 to 2 weeks.
The Space Transportation System (STS) is synonymous with the space shuttle. Moreover, the missions that these sophisticated vehicles undertook were prefixed with “STS,” for example, STS-129. The transportation system was partially reusable as every critical component could be used again except the fuel tank.
Key components of a Space Shuttle
The space shuttle consisted of three major components, each of which served a specific purpose:
Orbiter: This is the part that houses the astronauts. By the looks, it resembled a white airplane. This is the only component that leaves the Earth’s atmosphere, as the other two are jettisoned after use. Interestingly, while the orbiter launches using rockets for lift-off, it returns to Earth, gliding on its way back and landing on a runway like an airplane. The orbiters used by NASA were Atlantis, Challenger, Columbia, Discovery, and Endeavor.
Solid rocket boosters: This pair of rockets helped the space shuttle lift off of the ground against gravity using solid propellants. These boosters get detached from the rest of the parts about two minutes after launch. They would then drop into the ocean from where NASA would recover them for another mission in the future.
External tank: The external tank is the big orange-colored object on the space shuttle. It carried tons of liquid fuel for the space orbiter’s engines. This huge tank would burn out in Earth’s atmosphere after detachment from the orbiter. Therefore, it became the only key part that was not reusable.
Why did NASA retire it?
After being the central space transport for NASA for over three decades, the organization retired the space shuttle after its final mission ended on July 21, 2011. Moreover, the orbiter used for its farewell flight was Atlantis.
There were multiple factors that spelled its end. A big factor was that the cost of a mission, which was about $450 million, was too high to be feasible in the long term. Secondly, the turnaround time between completing a mission and the commencement of another was way longer than expected. It took the NASA spacecraft at least 54-88 days to be ready for another mission — much longer than the earlier projections of 1-2 weeks.
In addition, there were persistent qualms regarding the safety of astronauts. During its tenure, the space shuttle experienced two major disasters. The first was the launch failure of Challenger in 1986, and another incident involved the Columbia orbiter, which disintegrated after entering Earth’s atmosphere on its way back. Both these accidents killed the entire crew, causing seven deaths each.
Even though the space shuttle program effectively ended in 2011, the decision to shut shop was more or less taken during the Bush Administration. Since retiring from the space shuttle, NASA astronauts have traveled to low-earth orbit aboard Russia’s Soyuz spacecraft.
As private space organizations progress in this sector, NASA is working on STS’s successor, the Space Launch System (SLS). The organization proclaims it to be “the most powerful rocket we’ve ever built.” Improving on its predecessor, it plans to lower launch costs to just $2 million. As per various sources, SLS’s first launch will take place on 12 February 2022.
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