* Human Being on the Moon

A scientific, very respectful and well-thought reply to the popular question "Do you believe in UFOs?"  This book evolved as a reply to one of the most frequent questions that I used to hear from the public when I was working in an astronomical observatory: "Do you believe in UFOs?". That seems an odd question to ask to scientists, but after researching conscientiously for about a full year, I discovered, to my surprise, that mainstream Science has a few things to say about the topic.  This book is not about conspiracy theory, "NASA is hiding the truth", or much less, that flying saucers have already landed on the lawn of the White House. Rather, it is a book about what is the most rational reply that a scientist, or in my case, a science writer, can offer when people insist on asking that question.  As one advances through the chapters, explores the following rationale: Is there life in the Universe? The answer is yes: us. Are there civilizations capable of spaceflight? The answer is again yes: us. Can we expand those two questions? Can we answer also: "them" and "them"?  All illustrations are also available at naturapop.com
Photograph: The transporter carries the space vehicle Saturn V / Apollo 12, 111 m high, at the beginning of the roll of 5,6 km from the High Bay 3 of the Vehicle Assembly Building to the Launch Complex 39A, on 8 September 1969. Credit: NASA.

Probably the technological feat of strongest memory in History are the first travels of human beings to the Moon. The Twentieth Century was a revolutionary century. Never in such a short period so many changes that altered the destiny of Humankind took place. Some opine that in the last 100 years there have been more advances than in the previous 1000 years.

It was in the Twentieth Century when we learned to fly. In 1927 Lindberg flew from New York to Paris nonstop. In 1947 Chuck Yeager broke the sound barrier with the X-1 and by the sixties millions of people were flying from one continent to another in big airliners thrust by ​​jets.

In the Twentieth Century electronics developed, which has changed our daily lives. In 1901 Marconi invented the radio. Then came television, transistors, electronic computers, microchips, and satellite transmissions.

It was also in this century that engineering reached such a level that definitely stopped being an artisan craft and became a central part of modern Society. The use of the Scientific Method, advanced math and revolutionary new management techniques have enabled unprecedented building works. Thus were born such wonders as the Panama Canal, highways systems, kilometric bridges, skyscrapers and even entire cities such as Brasilia, with billion-dollars investments, thousands of workers and years of effort.

But all this technological advancement, because of a characteristic of humans beings, was also used to destroy. We begin with the bayonet until reaching the atomic bomb. In 100 years, more people died in wars than in the previous 1000 years.

For half of the century, two great superpowers, as none seen before in History, divided the World: The United States of America and the Union of Soviet Socialist Republics. Separated into different cultures, opposite economic and government systems, and on different continents, they were at the so-called Cold War. By 1957 the situation was so tense that both mutually threatened each other with thousands of atomic bombs. And that year, the Soviets showed the World their newest weapon: the intercontinental ballistic missile. And they did so in a spectacular way: by placing in orbit, on 4 October, the world's first artificial satellite, Sputnik 1. This metal artifact of a size slightly larger than a basketball and weighing 84 kg was going around the world in just one-and-a-half hour, passing over the major nations of the Earth, including the United States of America. A month later people's imagination rose further with the launch of Sputnik 2, carrying a living being into space: the dog Laika. Many already started talking about that the day of human being itself venturing into space was not far away. But for the U. S., what was clear was that if the Soviets wanted, they could use that same missile to launch nuclear weapons into the heart of the United States of America, and there would be no way to stop it. So a frantic race to reach and surpass the Soviets in the area of ​​military missiles and the very utilization of space for "national purposes" began.

In 1958 President Eisenhower created the National Aeronautics and Space Administration, NASA. One of its duties is to take care of U. S. interests in space and develop the technology and programs to achieve this. As a first step, the most ambitious project of the moment was assigned to it: a human in space, known as Project Mercury.

But on 12 April 1961, the Soviets once again surprise the world. Yuri Gagarin circled the Earth in 108 minutes in the Vostok 1 capsule. For the U. S. the situation was critical. The fact was undoubtedly historic, a great triumph of the human being, but also demonstrated that Soviet missiles were more powerful and presumably more reliable than U. S. missiles. And even more: the Soviet Union was always considered a country of peasants, backward, with a political and economic system that could not work. The regime of Nikita Khruschev made intensive propaganda over key points: that now Soviet science and technology were the most advanced in the world. That communism produced better results than capitalism and liberal democracy. That, in view of these, all countries in the world were invited to follow the path of communism under the political-economic-military leadership of the Union of Soviet Socialist Republics.

By 1961 the United States of America had another administration. John F. Kennedy, considered by many historians one of the best presidents in the history of this country, immediately realized what the situation was. It was not only a matter of image and propaganda, but much more. He spoke of a new frontier that was opening up to humans, a new ocean: outer space. He warned about the danger of Soviet domination of this new ocean, of it being used for military purposes for attacks on U. S. territory for which there was no defense, the danger of the United States of America losing its leadership to the Soviet Union, in that turbulent decade of the 60s, characterized by the expansion of communism in the Third World, and the need to maintain the scientific and technological competence of the United States. He said that wherever humans should go, freemen should also be there. Therefore, he proposed an extremely bold commitment "of landing a man on the Moon and returning him safely to the Earth." (Special Message to Congress on Urgent National Needs, 25 May 1961, John F. Kennedy Presidential Library and Museum, Boston). He proposed still do so before the end of the decade, at a time when only one American had gone to space, for just 15 minutes. Kennedy received almost unanimous support, and thus came the largest engineering project in History: the Apollo Program.

Finally, the time has come to move from fiction to reality: How to go to the Moon? Worse yet: How to go to the Moon and back? In order to go a rocket was necessary, but to return a second one was needed, that should be taken to the lunar surface. And how to land it, because on the Moon it was not possible to use parachutes like the Mercury spacecraft did, as the Moon has no atmosphere? The best Western experts thought of three main methods:

The most obvious was a direct journey, where a giant rocket would carry a huge spaceship, which would descend using engines to fight the gravity of the Moon, slowing it to a soft landing, and whose top portion would be launched again to go the other way, escaping from the Moon and returning to Earth. The big problem would be all that fuel that would be used for the descent, and after that, the departure from the lunar surface. As it is known, up to 95% of the mass of a rocket is fuel, and running the numbers for a ship of three astronauts (ideal team for a week-long dangerous journey that requires constant alert) the total mass of the huge spaceship would be a frightening 75 ton. The construction of the mammoth rocket launcher that would be required for it, though theoretically not impossible at the time, was so full of complexities that it would not be possible to make it work before the end of the decade.

The second method was apparently easier and reasonable. The huge spaceship would be launched light and stocked in orbit around the Earth, which is 2/3 of the battle to the Moon, not in terms of distance but in terms of effort. Later this would get the 1/3 remaining thrust to reach the Moon. Two big rockets would be used, but smaller than the giant rocket (known as "Nova") of the previous method. A problem was that the second of the two rockets would have to take off within days after the first, rendezvous with it and fill-up from this. And there was still the need to develop the huge 75-ton spaceship. All this was technically very complicated, and it was thought that the difficulties could not be resolved before the end of the decade.

The third method, called lunar orbit rendezvous, was still bolder. It implied descending to and exiting from the Moon using "steps". Descending a spacecraft to an orbit around the Moon and then leaving it was only a third of the effort down and up. The other two thirds could be performed by another ship, smaller, a "lunar module" designed only for carrying astronauts to the ground for just a couple of days. It could not return to Earth, just climb a "step" into orbit around the Moon, where the mother ship, or "command module" would be waiting. The two ships combined weight was 45 ton, almost only half that of the huge spaceship of the other methods. The problem, however, remained the meeting and docking of two spacecraft in orbit in which, in order to happen, the orbits must be exactly the same, needing very difficult calculations in real time, because the ships are in motion and at great speed. But there was no need to transfer fuel. In 1962 this latter method was chosen.

With the configuration and mass of the spacecraft already set, now it was necessary to match a launch vehicle to them: 45 ton in lunar orbit was very different from 1,8 ton in Earth orbit, which was what the U. S. was doing back then with Project Mercury. The gigantic Saturn V (as it was called) was the largest, heaviest and most powerful rocket ever built. Designed at Marshall Space Flight Center in Huntsville, Alabama, under the direction of Wernher von Braun (who designed the Nazi's V2 ballistic missile and made the launch vehicle of the first U. S. satellite), it was 111 m tall, weighed almost 3000 ton and was propelled by engines generating no less than 180-million horse-power. The last of its three stages was able to reach 40 000 km/h.

Before humans landed on the Moon, it was necessary to know if it was possible to do this in the first place. The Moon is a strange world, different from Earth, and whether the minimal conditions to land a crewed spacecraft of several ton were present was a total mystery. NASA, along with the Jet Propulsion Laboratory of the California Institute of Technology, successfully sent several robot probes between 1964 and 1968 to the lunar attraction. The first series was the Ranger, which after several failures, managed to reach the Moon televising the fall with multiple cameras. These close-up pictures showed fine details never before seen by humans, because even with the best Earth-based telescopes craters or mountains smaller than several hundred meters could not be seen. The next step was to gently land small spacecraft to test techniques and to evaluate the consistency of the ground, its thermal and chemical properties; this was done by the Surveyor series of spacecraft. Finally, the third step was to make detailed maps of the lunar surface, looking for the best sites for crewed landings; this mission was commissioned to several Lunar Orbiter spacecraft. They all showed that the landing of the Apollos was possible, although it would not be child's play.

To develop and test the technology and methods that would be used by Apollo, especially the encounter in orbit, the ability of astronauts to work outside the spacecraft and their endurance on trips of up to two weeks in space, an intermediate project was assembled: Project Gemini. Launched in pairs in ships derived from the Mercury, in 10 crewed missions astronauts broke a series of records and for the first time the United States of America was ahead of the Soviet Union. Done this, now the time for Apollo was coming forth.

By 1967 two of the most complicated flying machines ever built were completed and ready for flight testing. Specified by the Johnson Space Center and developed and built by North American Aviation - Rockwell, the Command and Service Module of Apollo, with a total mass of 29 ton, was actually divided into two parts: the first, a capsule, a cone with room for three astronauts and for digital computers and other systems, was equipped with a heavy heat shield and large parachutes, for it would be the reentry module to Earth; the second, attached to the base of the capsule, was a large cylinder, the Service Module, carrying tanks with fuel and the big rocket engine to go down to lunar orbit and out of it when time to return to Earth, besides electricity generators and communication systems. The other ship, the Lunar Module, also specified by the Johnson Space Center, developed and built by Grumman, was a strange spider-shaped ship, 15-ton in mass, also with two parts: the descent stage, with legs, a throttleable rocket engine and tonnes of fuel to slow the descent to the lunar surface; and the upper stage, with computers, life-support systems for the two astronauts and an engine to return them to lunar orbit (incidentally, an engine without a back-up for that life-or-death function). All in all, the aerospace engineers' ultimate product were comparable to a nuclear submarine packed inside a Volkswagen van.

While these ships were being built in California and Long Island, respectively, the biggest two of the three stages of the Saturn V were tested in Mississippi, with an incredible noise, more than thunderous. The first, called S-IC, was contracted to Boeing to be built in Louisiana and was 42-m high by 10-m in diameter. Its five F-1 engines built by Rocketdyne in California burned 13 ton of kerosene and liquid oxygen per second. The second stage, S-II, was 25 m-high, was built by North American Aviation - Rockwell in California and its five Rocketdyne J-2 engines burned cryogenic liquid hydrogen and oxygen. The third and smallest stage, S-IVB, was built and tested by McDonnell-Douglas in California and its single J-2 engine also burned cryogenic liquid hydrogen and oxygen, the most-powerful fuel mix known. Above the S-IVB of almost seven meters in diameter, and separated by a ring of 24 locations containing the IBM computer and accessories (assembled in Alabama) to control the giant, would ride the Lunar Module and above it the Command and Service Module. With the astronauts at the top, they would be hurled at 11 km/s toward the Moon. Soon after launch the two spacecraft would be mated and would continue the journey as a single unit.

The missions were controlled from a new multi-million-dollar center built in Houston, Texas. In this center, which became operational in the middle of the decade and later named Johnson Space Center, in addition of overall responsibility for the design of the spacecraft, the astronauts would be trained and the lunar samples brought back by them would be analyzed under strict quarantine. It had communication systems via satellite dishes around the world and sophisticated computers to guide the ships. Meanwhile in Florida, the launch base was being built, a harbor to begin the journey. In the new Kennedy Space Center would be the largest building in the world by volume, over 50-stories tall with a base area of more than ​​3 city blocks, where the stages of the Saturn V coming mainly by barge would be mounted one on top the other, interconnected electrically, hydraulically and pneumatically between them and with the Apollo spacecraft. Now the whole vehicle would be tested extensively. Two launch pads were built next to the beach, some 6 km away from the assembly building and control rooms. To bring the assembled Saturn V / Apollo there, giant caterpillar vehicles were specially developed.

By early 1967 test flights were forthcoming. Apollo 1 with Gus Grissom, Ed White and Roger Chaffee, should test the Command and Service Module in orbit around the Earth. During a rehearsal test on the ground weeks before the flight, atop a Saturn 1B rocket, the capsule caught fire. The three men died. It was a tragedy for the U. S.: the first astronauts to die on a mission, and worse, before it began. The Apollo program suffered a serious delay: a year and a half to study the problem and modify the ships.

By that time the Soviet space program was also in serious trouble. The official decision ( kept secret) to go to the Moon was taken too late, in 1964. The first tests of the lunar ship, Soyuz, were made in a hurry, and the results were so disastrous that ended in tragedy: inside the Soyuz 1, veteran Vladimir Komarov was killed when even the parachutes failed. The Soviet's landing method was similar to the U. S.', with a rendezvous in lunar orbit between a lunar module and the Soyuz. The launch vehicle, the N1 was a bit smaller than the Saturn V: the ships were smaller and less sophisticated than the Apollos (incidentally, each mission would carry a total of only two cosmonauts: only one of them would walk on the Moon). The N1 was tested four times. It exploded the four times. In 1974, amid intense infighting and eroding goal, the program was formally abandoned, as secretly as it began.

In 1968 the Apollos finally took flight. Walt Cunningam, Wally Schirra and Donn Eisele tested during 11 days the systems of the Command and Service Module. The mission was called Apollo 7. Then, for Christmas of '68, with Kennedy's deadline about to burst (and with the USA already with reasons to believe in a crewed lunar Soviet program in motion, Aldrin & Malcolm McConnell, "Men from Earth", Bantam Books, New York, 1989) came a bold move: crewed test of the Saturn V, straight to the Moon. Frank Borman, Jim Lovell and Bill Anders became the first humans to see with their own eyes the far side of the Moon, and the Earth as never before, as a "big blue marble" (as the song goes, by Broadway composer and writer Skip Redwine, arranged by Norman Paris, Copyright  ©  1973 Alphaventure musicians: D. K. Butterfield, L. J. Mauro, A. Rongo, F. Cerchia, N. Paris, G. Sanfino, singers: D. Campbell and J. Olson, released as an album for A & M Records on 29 December 1973, popularized by the children's TV series "Big Blue Marble", ITT Corporation, New York, 1974-1983. The original description seems to be by Jim Irwin, lunar module pilot of Apollo 15, in "To rule the night: the discovery voyage of astronaut Jim Irwin", with William Emerson, Jr., registered on 17 September 1973 by the authors, publisher A. J. Holman & Co., Philadelphia, first edition, 1973, page 17. Of course, the first person to inform us that the Earth is blue was Yuri Gagarin, on 12 April 1961). After ten hallucinating orbits at an altitude of only 100 km from the lunar surface, they began the return to Earth. Three days later, the capsule shocked at 40 000 km/h against the atmosphere, with the men inside. As calculated, the heat shield protected them. In Apollo 9, in March 1969, James McDivitt and Russell Schweickart  were the first astronauts to test the lunar module (named "Spider") , around the Earth, while David Scott remained in the Command and Service Module "Gumdrop". Two months later the Saturn V, working at its full capacity, launched Apollo 10 to the Moon: it was the dress rehearsal. Tom Stafford and Gene Cernan descended in the Lunar Module "Snoopy" to just 14 km from the lunar surface, while John Young was waiting in the Command and Service Module "Charlie Brown". Everything was ready, the path was opened. The last 14 km were for Apollo 11.

Now Science met Mythology: a man was about to touch the moon! Choosing the first human to set foot on another world is not a trivial matter. History unravels in mysterious ways: planners differentiated between mission types (with letters) and mission ordering (with numbers), which according to the twisting development of the Program, like the Apollo 1 fire, the change of objective for Apollo 8 and delays in the development of the Lunar Module, were not always equivalent, so when the time came for the first lunar landing (the "G" mission)  the commander in line for this assignment (the "11th" Apollo) got it in great measure from external events. His Lunar Module pilot found his way to an Apollo slot because another astronaut (a neighbor of him) was tragically killed in an airplane crash; and the Command-and-Service Module pilot missed a seat on an earlier spaceflight due to a medical issue, which pushed him further down the line to Apollo 11.  But getting to be one of the chosen to fly on any of the Apollo missions was also not trivial. The three were in their late 30s and had wife and children. The commander Neil Armstrong, a civilian, was an aeronautical engineer and test pilot who helped develop the X-15 aircraft at NASA, until today the plane that flew fastest and highest in the world. He was a veteran of Gemini 8, the mission of the first docking between spacecraft, where he experienced an emergency due to defects with the controls and had to land early. Deke Slayton, the head of the astronauts, told them he would come off the Lunar Module "Eagle" first basically because it was easier to get out the door from his side. He would be followed minutes later by the lunar module pilot, Air Force Colonel Buzz Aldrin, fighter pilot and engineer with a doctorate in Astronautics from MIT, where he developed the mathematical method that could be used as a back-up to the computers to ensure the orbital rendezvous. He was the astronaut with the most experience in extravehicular activities: more than 5 hours, during the Gemini 12 mission. The Command-and-Service-Module pilot Michael Collins, aeronautical engineer and test pilot from the Air Force was also a veteran of Gemini, and because of his missed earlier assignment, he had trained twice for his task. 

In the morning of 16 July 1969 the most amazing trip in the history of Humankind began. One million people attended the liftoff of the gigantic Saturn V from Cape Canaveral. Three days later the travelers were arriving at strange beaches. Armstrong and Aldrin entered the "Eagle"  lunar module and began the descent while Collins stood behind in the "Columbia" module. According to specialists, the landing on the Sea of Tranquility was the most dangerous part of the mission. After minor problems with a communication antenna and a couple of alarms of computer overload, a few meters from the ground came the most feared. The spot to where they were about to land was a pretty rocky area. If Armstrong could not find very quickly a suitable place to land the fuel of the descent stage would run out and they should abort the mission or die on the fall. With the fuel quantity light on, they landed softly. Armstrong sent the expected sentence (corrected transcript available at the "Apollo Lunar Surface Journal", http://www.hq.nasa.gov/alsj): "Houston, Tranquility Base here. The Eagle has landed." It was done.

Hours later, on the night of 20 July, the world watched live on television when Neil Armstrong descended the stairs, stepped onto the Moon and spoke the immortal words: "That's one small step for (a) man, one giant leap for Mankind" ("Apollo Lunar Surface Journal", http://www.hq.nasa.gov/alsj). After collecting some samples quickly and passing them to Aldrin, this descended too. Together they explored this world of strange lights and shadows, without sound, where the weight of things and movements are different and the sky is forever black. They performed experiments, collected samples, and marveled at the landscape. Two and a half hours later they had to leave.

When they came to Earth were placed immediately, still on the aircraft carrier Hornet, in a special container to meet the strict quarantine. No one could rule out some sort of lunar contamination by microorganisms. Three weeks later they exited, and saw that nothing had been just a dream. They were hailed as heroes, not only national but global ones. They made ​​a tour of 24 countries and everywhere people wanted to see them, wanted to touch them. The three are History personalities forever.

Apollo 12, in November, could now stay longer on the Moon than the pioneer. Pete Conrad and Alan Bean landed the lunar module "Intrepid" just several meters of a Surveyor, who had arrived in Oceanus Procellarum years before them. They retrieved some parts exposed to space weathering and collected a good amount of lunar samples, while their colleague Richard Gordon waited in the "Yankee Clipper".

Apollo 13, April 1970, was the origin of the phrase "Houston, we've had a problem.". An oxygen tank in the service module exploded, leaving them without electricity. The descent on the Moon was canceled, and soon it was evident that even the return to the Earth of Jim Lovell, Fred Haise and James L. Swigert was compromised. Aided by an army of engineers and scientists on Earth, they used the lunar module "Aquarius" as life raft and as tug boat of the inert command module "Odyssey" and its vital heat shield. After going through four terrible days of cold and thirst and a tremendous psychological strain, the parachutes opened brilliantly in the sky of the Pacific Ocean. This reminded everyone that despite the spectacular triumphs of Apollo every space travel was a difficult, serious and dangerous thing and not routine at all.

When the program returned to be operational a year later, Apollo 14 completed the mission of Apollo 13 to the hills of Fra Mauro. Alan Shepard, the first American in space, and Ed Mitchell used a hand-drawn cart to carry scientific instruments and explore larger areas. Then Stuart Roosa with the command ship "Kitty Hawk" caught the crew module "Antares" to bring the men home.

In Apollo 15 in July and August 1971, the concept of the hand-drawn cart became a lunar automobile for David Scott and James Irwin. With it they traveled further, many kilometers away from the "Falcon" lunar module and explored the Hadley-Apennine region. Above, Alfred Worden used a package of sensors aboard the command ship "Endeavour" and even let out a subsatellite.

In Apollo 16 with the spacecraft "Casper" and "Orion" John Young, Ken Mattingly and Charles Duke studied the highlands north of the crater Descartes in April 1972. Young and Duke also used a lunar electric car for their explorations. The amount of lunar samples brought was increasing.

Finally, in December 1972, half a million people attended the night launch of the last trip of astronauts to the Moon. A novelty in the Apollo 17 mission was that along with Gene Cernan and Ronald Evans flew a scientist, geologist Harrison "Jack" Schmitt. Until then only pilots, with engineering degrees or equivalent, had traveled. So, the first scientist on the Moon would also be the last man to go down the ladder and disembark there. But the 17 was also one of the most productive missions. During the 3 days they spent on the lunar surface in Taurus-Littrow, Cernan and Schmitt collected more than 100 kg of rock and soil, some very strange, and performed a good amount of experiments. Finally, after Cernan closed the hatch of the lunar module "Challenger" for reuniting it with the return spaceship "America", no other human footprint was stamped on the Moon as of today. There is no prediction of when it will happen again, nor who will be.

Apollo confirmed, especially with its treasure of nearly 400 kg of material from the Moon, that this it is a very old world, much as the Earth (indeed, with this data it was possible to calculate the age of our planet and even of the Solar System, at more than 4500 million years). Perhaps in the past it was part of the Earth, starting orbiting it from the resultant debris of some violent collision. The Moon is a dead world, and it has been so since long ago. It holds a virtually intact record of changes in the Solar System through the ages, which serves to calibrate the history of other planets and satellites of the Solar System. Most of what we know today about the Moon is due to Apollo. The Apollo Program was even able to comply with the political, military, economic, scientific and technological objectives devised by Kennedy. But as Neil Armstrong said in an interview broadcasted by CNN on the 30th Anniversary of start of the trip of Apollo 11, the biggest success of Apollo was to make many people dream that our opportunities have no limits. Now our goals certainly go further than the Moon, because Humankind is no longer inescapably tied to just one planet.

A. L.

S. C., SP, 28 January 2001.

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From a lecture given at USP, originally on 22 November 2000. Originally posted by UNICAMP, from a document dated 28 January 2001. An abridged version was published in ABC Color on 23 July 2006. Photograph: The transporter carries the space vehicle Saturn V / Apollo 12, 111 m high, at the beginning of the roll of 5,6 km from the High Bay 3 of the Vehicle Assembly Building to the Launch Complex 39A, on 8 September 1969. Credit: NASA.

A scientific, very respectful and well-thought reply to the popular question "Do you believe in UFOs?"  This book evolved as a reply to one of the most frequent questions that I used to hear from the public when I was working in an astronomical observatory: "Do you believe in UFOs?". That seems an odd question to ask to scientists, but after researching conscientiously for about a full year, I discovered, to my surprise, that mainstream Science has a few things to say about the topic.  This book is not about conspiracy theory, "NASA is hiding the truth", or much less, that flying saucers have already landed on the lawn of the White House. Rather, it is a book about what is the most rational reply that a scientist, or in my case, a science writer, can offer when people insist on asking that question.  Of course, "Do you believe in UFOs?" is, understandable, one of the most popular questions that common people ask (even if silently, to themselves) when they raise their eyes and look at the stars. So it has to be treated respectfully, and why not, given a well-thought reply.