The Moon has attracted the eyes and wonder of mankind since ancient times. Its light has guided everyone from hunters to travelers. The first calendars were based on the changing phases of the Moon, and our four-week months still follow the length of the lunar cycle. This nearest cosmic neighbor of our planet has been an object of worship, with beautiful myths, legends, and poems composed in its honor.
Thus, it was only natural that the Moon was the first celestial body to which spacecraft were launched and which humans visited in person. Today, we are going to talk about the history of how mankind conquered the Moon. The first article in our series is devoted to the “classical” period of lunar exploration, from the beginning of the space age to the end of the lunar race between the USSR and the USA.
Early exploration of the Moon
The first attempts to explore the Moon date back to antiquity. In the 3rd century B.C.E, Aristarchus of Samos calculated that the radius of the Moon was about three times smaller than the radius of the Earth (which ended up being fairly close to accurate), and that the Sun is about 19 times farther from the Earth than the Moon (here he was off by a factor of about 20). In the 9th century C.E., Persian astronomer Habash al-Hasib estimated the Moon’s radius at 1520 km, and the distance between the Earth and the Moon at 346,000 km, which was a very good estimate for that time (compared to the real values of 1,740 km and 384,000 km).
The invention of telescopes ushered in a new era of lunar study, as they allowed astronomers to begin examining the Moon’s surface in detail. The first lunar maps were published in the middle of the 17th century. At that time, it was common to refer to the Moon’s dark regions as ‘seas,’ as it was believed that the Moon was similar to the Earth and that it had bodies of water.
However, as science developed, it became clear that this understanding was mistaken. In the middle of the 18th century, it was proven that the Moon had no atmosphere. In the early 19th century, a theory emerged that the craters dotting the Moon’s surface were created by meteorites. Gradually, astronomers managed to determine the size of the Moon, its mass, and its distance to the Earth with fairly high accuracy. Later, the appearance of photography made it possible to compile detailed atlases of the lunar surface.
However, although the Moon had been studied more comprehensively than any other body in the solar system by the beginning of the Space Race, humanity’s knowledge about it remained scarce compared to what we know now. Scientists did not know if the Moon had a magnetic field. An even bigger mystery was its origin. Astronomers had three main theories: that the Moon had at one point been separated from the Earth, that the Moon had been captured by the Earth’s gravity, and that the Moon and the Earth had been formed at the same time. Each of these theories had its supporters, and they debated the issue passionately. There was also debate about the nature of lunar craters. Before the beginning of the space age, the prevailing point of view was they were mostly of volcanic rather than meteoric origin.
There was no consensus on what made up the Moon’s surface. Some scientists believed that it was composed of a thick layer of cosmic dust, and that any attempt to land upon it would cause the descent vehicle to simply sink. Finally, no one knew what was on the far side of the Moon, which is never visible from Earth.
There was only one way to get answers to all these questions: sending a spacecraft to the Moon.
The early years of the Space Race
The first attempts to send a spacecraft to our nearest cosmic neighbor were made less than a year after the beginning of the space age. This was no surprise, as a successful lunar mission promised very large political dividends. Both the USSR and the US wanted to take advantage of this opportunity.
Interestingly, the very first launch to the Moon (Pioneer 0 apparatus) was carried out by the American Air Force. In fact, the law on the founding of NASA was signed 19 days before thе launch event (on July 29, 1958) and the new department simply had not had time to start its work. Alas, the mission ended with the rocket exploding.
The first spacecraft to reach the Moon were the Soviet Luna-1, Luna-2, and Luna-3. Launched in January 1959, Luna-1 failed to achieve its designated mission (crashing into the Moon and delivering a Soviet pennant), but it did discover that the Moon lacked its own magnetic field. In September 1959, Luna-2 accomplished its predecessor’s mission, and a month later the Luna-3 transmitted the first ever photographs of the Moon’s far side. All this success cost the Soviet Union four lost vehicles, of which the failed launch attempts, of course, were not reported.
However, the situation in the United States was much more frustrating. Between 1958 and 1960, the Americans made eight attempts to launch something to the Moon. Seven vehicles were lost in rocket failures. Only the Pioneer 4 probe achieved any sort of success, reaching space and passing 60 thousand km from the Moon.
The atmosphere of the Cold War left its mark on the early lunar missions. In fact, the Luna-3 spacecraft took its famous photographs on camera roll taken from … scavenged American stratospheric reconnaissance balloons. The fact is that the camera roll produced by the Soviets simply didn’t have the capacity to withstand the radiation involved.
It was only after the end of the Cold War that the public learned that both the USSR and the USA had considered equipping lunar probes with nuclear explosives. The plan would have been to detonate the devices in the area of the lunar terminator line (the line separating the dark and illuminated sides of the Moon), which would have made it possible to see the explosion with the naked eye from Earth. Of course, from a scientific point of view, such a test would be of extremely low value. The main motivation for both sides was pure ideology. The explosion was supposed to demonstrate the technological might of the country that carried it out and prove that the apparatus sent to the Moon had actually reached its surface. Fortunately, the superpowers ultimately abandoned these dubious plans.
It is interesting to note that after the flight of Luna-3, the next successful Soviet lunar mission didn’t take place for another six years. This long break is explained both by the still very low reliability of rocket technology and by the Soviet space program’s increased ambition. Soviet scientists decided to make a soft landing on the Moon, which was a far more difficult task than simply having a spacecraft ram into it.
Between 1963 and 1966, the Soviet Union made twelve attempts to land an unmanned probe on the Moon. Six of the probes were lost as a result of rocket failures or upper stage failures. Two probes failed to reach the Moon due to trajectory calculation errors, while three crashed during landing. Only Luna-9 was successful, and it would be the last spacecraft in which the father of Soviet rocketry, Sergei Korolev, took part. The probe made a soft landing on the Moon on February 3, 1966, disproving the theory that the Moon’s surface was mere space dust that could not support any weight, and proving that a Moonwalk would be possible.
Meanwhile, NASA was growing tired of repeated failures, and they decided to lower their bar and try to do something simpler. If America’s early years of the space race were spent unsuccessfully trying to put a satellite into a selenocentric (circumlunar) orbit, then the task of the new Ranger program was to obtain detailed photographs of the lunar surface. However, this also turned out to be quite difficult, and full success wouldn’t come until 1964 with the Ranger 7.
The Battle for the Moon Gains Steam
By the second half of the 1960s, the Moon race had already moved into a new stage, from a competition of “who will do some thing first” into a fight to be first to land a man on the Moon. This was formally started back in 1961, when John F. Kennedy asked Congress for funding for a manned lunar mission. And already at the beginning of the next year, he read the famous speech in which he promised to land a man on the Moon before the end of the decade. Symbolically, the speech was delivered in Houston.
Interestingly, before this speech, Kennedy wrote a letter to Soviet Premier Nikita Khrushchev in which he proposed cooperation in space exploration, including the joint organization of a flight to the Moon. However, the USSR did not take his proposal seriously, and did not bother to reply. Had they done so, the history of astronautics could have taken a completely different path.
In the battle for the Moon, NASA relied on the super-heavy launch vehicle Saturn V. Its had a length of 110 meters and a weight of 3000 tons. It remains the heaviest rocket in history. Saturn V was supposed to deliver the Apollo spacecraft and its crew of three to the Moon. After entering selenocentric orbit, one astronaut would remain in the command module, while two would land on the Moon and walk on its surface.
Of course, this rocket and ship wouldn’t appear out of nowhere. Building them required an enormous amount of work. Production facilities, mission control center buildings, an assembly hangar for the rocket, test facilities, simulators, and rocket conveyors would all have to be constructed. Crews would have to be trained. But all of this was doable; it was simply a question of money.
And NASA had the money. A whole lot of money. In the mid-1960s, the United States began spending up to 4% of its federal budget on space. Almost all of this went into the Apollo program. There were 400 thousand people working on various projects connected with it. Such resources had never been allocated to space exploration either before or since.
But in addition to creating the necessary infrastructure and technology for the launch of a manned lunar spacecraft, NASA also needed to learn a significant deal about the Moon in order to organize future expeditions. For this, the agency launched two new programs with automated devices.
With the Surveyor project, the Americans worked out the technology for landing on the Moon. In total, seven devices were launched under the project, five of which were successful.
In order to select landing sites for future expeditions, NASA also needed to obtain high-quality, high-resolution images of the entire lunar surface. This task was assigned to the Lunar Orbiter program. Under this program, from 1966-1967, NASA put 5 spacecraft into selenocentric orbit. They mapped 99% of the Moon’s surface with a resolution that was orders of magnitude greater than the capabilities of the most powerful ground-based telescopes of the time.
Another important achievement of the program was the discovery of mascons – lunar gravitational anomalies that cause deviations in the orbits of satellites in selenocentric orbits. Data analysis from the Lunar Orbiter program allowed engineers to significantly improve the navigation accuracy of subsequent missions.
Meanwhile, the Soviet Union initially didn’t take the Apollo program seriously. In fact, the Soviets only really entered the race to land a man on the Moon in 1964, meaning the Americans already had an almost three-year head start. The second problem was that the Soviet economy simply could not provide the same resources for their lunar project as could the United States. Moreover, as strange as it may sound, the Soviet Union sorely lacked centralized space efforts. The USSR did not have its own NASA. Instead of a single organization supervising space, there were several different design bureaus that each fought desperately for state orders, and their leaders were often openly at odds with each other.
As a result, the Soviet leadership decided to split the lunar program into two independent projects. The first was focused on flying to the Moon, while the second was focused on landing astronauts on the surface. Each of these programs was supposed to use a different launch vehicle and a different spacecraft. Of course, this scattering of resources could not lead to their desired results.
One Small Step
The path to the Moon was no cakewalk for the United States. Even with huge financial resources, they could not avoid all setbacks. For example, in January 1967, during ground tests of the Apollo spacecraft, a fire erupted which killed three astronauts. This had a serious impact on the program, forcing safety standards to be significantly revised, and the first manned flight to eventually be shifted back by a year and a half.
In theory, this event gave the USSR the opportunity to catch up with the Americans. Soviet specialists decided to push forward with the first flight of the Soyuz, which was to become the basis for future lunar ships. This decision turned out to be a serious error. The Soyuz-1 mission ended with the death of cosmonaut Vladimir Korolev. The catastrophe led to USSR also pausing their manned space flights for a year and a half.
1968 was a decisive year in the lunar race. The United States conducted a successful test of its Saturn V rocket, and then launched the Apollo 7 manned mission. By that time, the Soviet designers had already understood that they had most likely lost the race to land on the Moon. But the USSR still had the hope of being the first to fly around it.
This hope was shattered by repeated accidents during unmanned tests, mainly related to the poor reliability of the Soviets’ Proton rocket. In turn, the Americans, who learned about these tests, revised their flight schedule and decided first to carry out a mission for a manned flyby of the Moon, and only then to test their lunar module in space. As a result, in December 1968, the Apollo 8 spacecraft with a crew of three astronauts successfully flew around the Moon. Shortly thereafter, the USSR completely scrapped its flyby project, not willing to fight just for second place. In February 1969, the Soviet space program sustained another heavy blow when the first test of their H1 super-heavy rocket ended in failure due to a failure of the rocket’s first stage. This finally buried the plans of the USSR to land the first man on the moon.
In March 1969, the crew of Apollo 9 successfully tested their lunar module. In May, the Apollo 10 expedition set off for the Moon, conducting a dress rehearsal for a future landing. The lunar module with two astronauts separated from the command module, and then flew over the area selected for the site of the first human landing.
And so, on July 16, 1969, Apollo 11 blasted off for the Moon. Four days later, its lunar module landed on the surface, Neil Armstrong set foot on the surface and uttered his famous words, “That’s one small step for man, one giant leap for mankind.”
The telling of the story about human trips to the Moon often ends at this point. In reality, although the flight of Apollo 11 had exceptional political and symbolic significance, from a scientific point of view, it was more of a demonstration mission that proved the possibility of people working on the Moon’s. Each subsequent lunar expedition would spend more and more time on the Moon, solving more and more complex problems. It is thus worth adding a few words about them.
Apollo 12 flew to the Moon in November 1969. Its launch took place in rather extreme conditions. The launching rocket was struck by lightning twice. NASA specialists even feared that they damaged the ship’s parachute release system, but these fears fortunately turned out to be unfounded.
The Apollo 12 mission was also interesting in that its lunar module landed next to the Surveyor 3, which landed on the Moon in 1967. Its astronauts thus took on the role of sort of cosmo-archaeologists. They studied Surveyor 3 and returned some of its parts, including its camera, back to Earth. There, bacteria were found in a piece of foam placed in a nutrient medium. Scientists are still debating whether they got on the device during preflight maintenance (in this case, the bacteria managed to survive travelling to the moon and staying there for almost three years), or whether they were accidentally brought in after returning to Earth.
As we all know, the Apollo 13 mission, launched in April 1970, ended in an accident that nearly cost the crew their lives. But at the same time, the ship itself demonstrated excellent survivability, and NASA’s actions to rescue the expedition even strengthened the organization’s reputation. Because of this, the Apollo 13 flight is sometimes called a “glorious failure.”
Launched in January 1971, Apollo 14 fulfilled its predecessor’s mission. The astronauts landed in the Fra Mauro crater, which, unlike the landing site for previous expeditions, is located in the continental region of the Moon.
The final three lunar missions were significantly different from their predecessors. They used a modified version of the lunar module, capable of taking more scientific instruments, equipment, and supplies. This made it possible to increase the time the crew spent on the lunar surface. While the first missions were only able to remain on the Moon’s surface for a day or a half, this module could support stays of three days. But the most important extra cargo was the lunar rover which was loaded onto the module. This made it possible to significantly expand the area that astronauts could explore. In addition, unlike previous missions, expedition members began to undergo full-fledged geological training, which significantly increased the missions’ scientific output.
Apollo 15 (July 1971) made history as the manned mission that landed farthest from the lunar equator. Astronauts landed at Hadley Furrow, a canyon formed by a once-flowing lava flow. After the completion of the flight, experts called the samples delivered by the expedition “the richest catch” of the entire program, and the mission itself – “one of the most brilliant from the scientific point of view.”
For its part, Apollo 16 (April 1972) was the first to set down in the mountainous region of the Moon. Its astronauts also collected a rich harvest of geological samples and set up an ultraviolet telescope, thus creating the first extraterrestrial observatory.
The last manned lunar expedition of the 20th century was Apollo 17 (December 1972). It was also noteworthy for its inclusion of geologist Harrison Schmitt. He became the first )and so far only) scientist to visit the Moon. All other astronauts had begun their careers as military pilots. The Apollo 17 crew set records for both the length of time spent on the Moon and the number of samples collected.
End of the Moon race
According to the recollections of Eugene Cernan, the last person to stand on the surface of the Moon, when he returned to Earth, he was sure that a manned station would be built on the Moon would be built by the end of the 20th Century. But Cernan would unfortunately be wrong.
The Apollo program was primarily initiated for political reasons – the desire of the United States to avenge their defeats at the beginning of the space race. Moreover, the American government was willing to spend extravagantly to get what it wanted. Unfortunately, once its objective was achieved, it was not ready to continue funding the program. Space budgets had begun to decline rapidly already by the late 1960s. At some point, there was such rapid turnover that the continued existence of NASA was questionable. It’s thus not surprising that after Apollo 17, America forgot about the Moon for almost a quarter of a century.
However, the data and samples collected by lunar expeditions were enough to provide scientists with work for many years to come. Of course, the study of the Moon has not yet led to any fundamental breakthroughs in the understanding of the universe. It has, however, significantly enriched our knowledge of celestial bodies and the history of the solar system. In particular, isotope analysis of regolith samples completely refuted all three of the old theories on the Moon’s origins. This gave birth to a fundamentally new theory in which the Moon is thought to have been formed as a result of a collision between Earth and a protoplanet.
As for the USSR, Soviet engineers continued to work for several more years on programs to land a man on the moon by virtue of sheer inertia. Several unmanned tests of lunar spacecraft were carried out, and new attempts were made to launch the H1. But unfortunately for them, they all resulted in failure again.
In the end, the Soviets’ manned Moon landing program met the same fate as their Moon flyby projects. In 1974, all work on H1 was discontinued, as was the development of a project to create lunar bases. The USSR did not want to come second again. Instead, the Soviets decided to deploy a rocket which was never intended for lunar flight, and instead of risking human lives like their prideful American adversaries, they decided to entrust all their work to automated machines.
By the way, automatic devices have really become a silver lining in the lunar clouds for the country of soviets. In the 1970s, the USSR managed to land a pair of the first rovers in history on the Moon. Thirty years later, NASA’s Mars rovers took their baton. Moreover, several Luna missions were able to accomplish an even more impressive task: landing on the Moon, taking samples of its soil, and then delivering them to Earth.
But still, the bitterness of defeat was so strong that in the end, the Soviet program for studying the Moon with automated machines was curtailed. Launched in 1976, Luna-24 was the last Soviet spacecraft to visit our planet’s nearest neighbor. There has not been another one since.