On July 8, 2011, the STS-135 mission was launched into space from the Cape Canaveral Spaceport. It marked the conclusion not only of the space shuttle Atlantis’s operational history but also of the entire space shuttle program. Subsequently, a new and contemporary chapter in the history of American space exploration commenced.
Mission STS-135
Fifteen years ago, on July 8, 2011, the STS-135 mission commenced. The Space Shuttle Atlantis conducted a spaceflight lasting twelve days, eighteen hours, and twenty-eight minutes. The crew comprised four astronauts: mission commander Christopher Ferguson, along with Douglas Hurley, Sandra Magnus, and Rex Walheim.
All four individuals were familiar with space travel. For Hurley, this was his second mission; for the others, their third. The mission itself was not notably challenging: the spacecraft successfully docked with the International Space Station, where the crew unloaded 4.2 metric tons of various supplies essential for the station’s operations from the “Raffaello” transport module. Subsequently, they loaded a significant quantity of cargo into the same module for return to Earth and successfully completed the mission.
Essentially, throughout the majority of the flight, the spacecraft was docked to the station, and the crew functioned as cargo handlers. Nonetheless, they received a distinguished reception upon their return to Earth. Notably, John Young, the commander of the inaugural mission under the Space Shuttle program, was present. This occasion marked the final mission of Mission 135, the concluding chapter of the program. To truly appreciate its significance, one must comprehend the origins of the Space Shuttle era.
Space shuttle
The 1950s and 1960s, heralded as the inception of the space age, were characterized by an intense race for achievement. The primary objective — still unaccomplished by competitors — was of paramount importance. The expenditures associated with attaining this goal were not meticulously documented. The United States ultimately prevailed in this period by successfully executing six lunar missions between the years 1969 and 1972.
Nevertheless, concurrently, American society grew progressively indifferent towards space exploration. The sector necessitated considerably substantial financial resources. NASA promptly recognized that it risked losing all funding and consequently commenced to modify its strategic plans. With profound regret, the engineers relinquished the Moon exploration initiative and redirected their efforts toward the optimal utilization of Earth’s orbit.
One of the primary issues in the past — and still persisting today — was that each rocket was a compilation of high-technology equipment that became scrap metal after each flight. To mitigate this problem, the concept of the “space shuttle” was introduced — a spacecraft that launches like a rocket, lands like an airplane, and can be reutilized following maintenance.
The journey was arduous; however, by the early 1970s, the United States had attained significant progress in this domain. I refer specifically to the X-15 rocket aircraft, which was employed for high-altitude flights during the first half of the 1960s, with some models even surpassing the Kármán line, the conventional demarcation of space.
In the USSR, incidentally, there was no such program, so it turned out to be easier to pursue a different path there: space stations and long-duration expeditions to them. However, even for the United States, implementing the Space Shuttle program proved to be extremely difficult. It began in 1971, but by 1975, the Apollo spacecraft — which had been built for the Moon — were still being used for the few flights to Earth’s orbit (for example, to the Skylab space station).
However, subsequent to the Soyuz-Apollo mission, NASA did not undertake any manned spaceflights for a period of six years, during which time the agency solely launched satellites. At that juncture, the United States commenced a rapid decline in its advantageous position acquired in the space race.
Meanwhile, the American industry was actively engaged in the development of the world’s inaugural reusable spacecraft. The project generated 200,000 employment opportunities and amounted to a financial expenditure of $7.5 billion.
The outcome was a spacecraft unlike any previously encountered by humanity. From an external perspective, it appeared as a somewhat cumbersome aircraft, measuring 37 meters in length with a wingspan of 24 meters. However, in actuality, it was a sophisticated system capable of transporting 29.5 metric tons of cargo and a crew of seven into orbit.
Furthermore, it did not necessitate a dedicated launch vehicle. The Space Shuttle itself was equipped with engines capable of producing sufficient thrust to counteract Earth’s gravity. During the launch procedure, it was positioned vertically, with a 47-meter-tall fuel tank attached — taller than the spacecraft itself — and two solid-fuel boosters affixed to either side.
Among these components, only the fuel tank was intended for disposal; all other elements were reusable. However, what was particularly remarkable was the dimensions of this object: it featured an internal compartment specifically designed for the manual placement of very large satellites into orbit. It was capable of comfortably accommodating two Soviet “Soyuz” spacecraft in their orbital configuration, with their solar panels folded.
The success of the reusable spacecraft
It is worth noting that the Soviet Union had been monitoring the Space Shuttle program from its inception. However, their understanding of the spaceplane concept differed significantly. Primarily, it was not conceived as a cargo laboratory but rather as a space bomber. Consequently, it was to be smaller, and from the beginning, it was designed for launch from an airborne carrier rather than a vertical launch.
However, Soviet engineers appropriately regarded these ideas — represented by the “Spiral” project — as more intricate. Consequently, limited resources were allocated to them. The situation changed following the test flight of the Enterprise shuttle in 1977.
The initial prototype of the space shuttle did not reach space; following five atmospheric tests, it was abandoned on Earth. Nonetheless, the Soviet Union concluded that developing an original engineering philosophy was unnecessary and instead opted to replicate the American design while expeditiously training pilots to operate it.
Nevertheless, the deployment of the American space shuttle was not expeditious. An additional four years elapsed following the initial test before another shuttle, Columbia, was positioned on the launch pad for the inaugural time. Nonetheless, the date selected for this event was highly symbolic — April 12, 1981 — precisely twenty years subsequent to Yuri Gagarin’s historic launch.
That flight was a notable achievement. At a certain juncture, the United States unexpectedly advanced in the space race, which it had previously started to relinquish. This was attributable to the fact that the Space Shuttle was capable of transporting up to seven astronauts into orbit simultaneously, and these spacecraft could be launched substantially more often than the Soyuz spacecraft.
At one point, the “shuttle” itself became a symbol of American space exploration. However, unexpectedly, triumph transformed into tragedy. On January 28, the space shuttle Challenger exploded shortly after launch, resulting in the loss of all seven astronauts aboard.
The flights under the Space Shuttle program were temporarily suspended, and plans for constructing new shuttles were consequently canceled. However, subsequent to this pause, the initiative to utilize reusable spacecraft was revived. This was largely due to the fact that, apart from this, the United States lacked other manned spaceflight endeavors, and the program itself appeared exceedingly promising.
Ultimately, following the Challenger disaster and the transformation of the Enterprise into a museum exhibit, four shuttles remained in the United States: Columbia, Atlantis, Discovery, and Endeavour. These shuttles were utilized extensively in subsequent years. Notably, the renowned Hubble Space Telescope was launched into space with the assistance of one of these shuttles.
The Soviet Union disintegrated, and at a certain juncture, the “shuttle” itself emerged as the emblem of spacecraft in general. Consequently, it was necessary for it to partake in international initiatives. The United States appeared unable to initiate its space station program effectively. russia possessed the “Mir,” an aging yet operational station. Other nations had minimal capabilities but expressed a keen interest in participating.
The following solution was identified. The “shuttles” assumed a substantial role in delivering the necessary supplies to the “Mir” station; subsequently, the aging station was scheduled for deorbiting, and the International Space Station (ISS) was to be launched in its stead through a collaborative effort. Furthermore, the supply chain for the ISS was heavily dependent on American “space trucks.” It appeared as though their prominence would persist indefinitely.
Ultimately, all actions were executed according to the original plan; however, another catastrophe ensued. In 2003, the Columbia, the inaugural American space shuttle, was lost during re-entry into the Earth’s atmosphere. Once more, all astronauts on board lost their lives. This incident compelled engineers to reevaluate the aging condition of these unique spacecraft and the escalating risks associated with their operation.
There was no method available to construct new units nor was there any replacement. It was consequently decided to gradually retire them while exploring alternative means to transport American astronauts into space. Therefore, the STS-135 mission unequivocally signified the conclusion of the space shuttle program. Typically, with each NASA launch, the subsequent mission was already in preliminary stages of preparation, should unforeseen circumstances in space hinder the astronauts’ return to Earth.
Nevertheless, there was no rescue mission designated for STS-135. In the event of issues arising in orbit, they would return via a russian “Soyuz” spacecraft. This situation exemplifies the circumstances faced by the United States space program following the retirement of the space shuttles.
After the “shuttle”
Eight years elapsed between the Columbia disaster and STS-135. During this period, all parties prepared diligently for the upcoming event. The russian space agency increased production of the Soyuz spacecraft, recognizing the likelihood that the United States would depend on them, thereby anticipating a rise in their reliance on russian technology.
Meanwhile, NASA sought a means to expedite its escape from this predicament. Initially, the Constellation program spacecraft were regarded as potential solutions. It was anticipated that, besides lunar missions, they would also be capable of executing missions in Earth’s orbit. However, concurrently with the final shuttle missions, it became evident that the program had not succeeded; consequently, it was ultimately rebranded as Artemis, and the pursuit of a solution was redirected to private enterprises.
In 2012, SpaceX’s Dragon cargo spacecraft successfully docked with the International Space Station (ISS). As it was already a reusable spacecraft, efforts were initiated to address this feature further by developing a crewed variant. This variant was intended to be paired with Boeing’s Starliner. However, the outcomes did not meet initial expectations.
The crewed variant of Dragon received certification for flight in 2020. As of 2026, Starliner had conducted only a single crewed mission, which was unsuccessful. NASA continued to rely on the russian “Soyuz” spacecraft for a period exceeding the interval between the final Apollo mission and the inaugural Space Shuttle flight. Furthermore, that reliance has not been entirely eliminated to date.
From a purely theoretical perspective, Starship — in its original conceptualization — could signify a significant breakthrough comparable to the advent of space shuttles. Nevertheless, at present, even its cargo version remains classified as experimental.
It appears that, fundamentally, the crisis resulting from the retirement of NASA’s space shuttles has not yet been resolved. It continues to represent the pinnacle of American space engineering.
