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For All Humankind. Tanya Harrison
Читать онлайн.Название For All Humankind
Год выпуска 0
isbn 9781642500974
Автор произведения Tanya Harrison
Издательство Ingram
For the Apollo program, NASA put three astronauts in a capsule, put the capsule on top of a rocket, and launched them toward the Moon. This sounds simple enough, but there was one minor detail to attend to: No one had ever built a rocket that was able to do this. No one had ever built a rocket that could lift a spaceship and three people at a fast enough speed that they could escape the gravity of Earth and get to the Moon.
To add to NASA’s problems, no one had ever designed a spacecraft able to land on another world and take off again. Both NASA and Russia had sent robotic missions that landed on the Moon in the late 1960s, but none of these were designed to return to Earth or carry humans.
After exploring all the options for getting to the Moon, landing, and getting home, NASA came to a conclusion: they needed one very big rocket and two different spacecraft.
The plan went like this: The massive rocket would have the two spacecraft placed on top of it. There would be three astronauts onboard, right at the top. The giant rocket would push both spacecraft into space. Once in space, while still near the Earth, the two craft would connect and start flying towards the Moon. The rocket would then fall back down to Earth having completed its job.
Once the two spacecraft got to the Moon a few days later, they would detach from each other. One would remain flying above the Moon (staying in orbit) with one astronaut onboard. The other craft, carrying two astronauts, would land on the Moon’s surface.
The astronauts that made the journey down to the lunar surface would walk around for a bit, collect some rocks, then launch off the Moon back up to the other spacecraft that had remained in orbit. Thankfully, it’s much easier to launch off the Moon than the Earth because there is no atmosphere, as well as much less gravity holding you down. Getting off the Moon only requires a small booster.
After getting off the Moon and reaching the other craft, the two would reconnect and the Moonwalking astronauts would rejoin the third that had stayed in orbit above them. Reunited in the same spacecraft, the three astronauts would make their way back home to Earth. Since they didn’t need two spacecraft to go back home, they would leave one to fall back down to the Moon just before they left.
As our three astronauts returned to Earth, the Command Module would fly through the atmosphere and deploy multiple huge parachutes—each one nearly half the size of an Olympic swimming pool—and land softly on the ocean. They would float there until being picked up by a naval carrier and brought back to shore.
No one said going to the Moon would be easy.
That Big Rocket:
The Saturn V
Next time you’re in a city, find a building that’s about thirty stories high. That’s the height of the rocket built by NASA to send humans to the Moon. The rocket was called the Saturn Five. The “five” is always written in Roman numerals, so it’s written out as “Saturn V.” To this day, over fifty years later, the Saturn V is still the most powerful vehicle ever built by humans.
Like a lot of rockets, the Saturn V was what’s called a multistage rocket. These rockets shed weight as they fly. This is good as lighter things can fly faster and will have an easier time escaping the pull of Earth’s gravity. Multistage rockets are built in sections (“stages”) and burn fuel from the bottom up. When the fuel from one section is used up, that section breaks off and the rocket becomes lighter.
Spacecraft 1: The Command/Service Module
The Command/Service Module was a three-seater capsule that sat right at the top of the Saturn V. When the Saturn V was on the launch pad, the astronauts would be sitting with their backs to the ground looking straight up at the sky. The only thing on top of this craft was a small escape rocket for emergencies. This escape rocket was like an ejection seat for all three astronauts, but it was only needed in case of an accident on the launch pad; it would be discarded right after takeoff if unused and wouldn’t go into space.
The Command/Service Module had two parts: the Command Module and the Service Module, hence the name “Command/Service Module.” The Command Module was a triangular capsule at the front where the astronauts sat and controlled everything. The Service Module was the cargo part of the spacecraft behind them. NASA figured it would take the astronauts about three days to get to the moon. This meant they would need about seven days worth of food, power, and oxygen to cover the day at the moon and the return trip. Essentially, the Service Module was the supply closet for the mission. To simplify things, from here on out, we’ll just call this whole craft the “Command Module.”
NASA also attached a very small rocket engine to the back of the Command Module so that the astronauts could make maneuvers on their way to the Moon. This was critical for entering the Moon’s orbit, which required precise flying to account for the Moon’s own, albeit weaker, gravitational pull. When an Apollo mission was over, the Command Module would return to Earth’s orbit from the Moon and split in two. Only the triangular “command” part with the three astronauts onboard would return safely to Earth’s surface. The supply closet that was the Service Module was left to orbit the Earth and eventually crash into the ocean.
Spacecraft 2: The Lunar Module
At this point we’ve got a big rocket, a place to sit and control the spacecraft, and a place to keep all the important things like food and oxygen. So, what else do we need? Well, a huge part of going to the Moon was flying down to the lunar surface, landing, and being able to come back.
For this part, NASA had some decisions to make. They realized that the Command Module couldn’t perform the actual moon landing once it got there. Instead, the solution was to build an entirely separate spacecraft that came along for the ride and would only be used for going up and down to the lunar surface. This craft would attach to the front of the Command Module for the trip to the Moon, kind of like driving to a lake with a canoe on the roof of your car. The second spacecraft was designed specifically to land on the moon, and was called the Lunar Excursion Module, or LEM for short (pronounced like the beginning of “lemon”).
The LEM looked a bit like a robotic spider. It was designed only for landing on the Moon and getting back off again. After landing, the LEM would be the astronauts’ home base—their tent in the woods, so to speak. When they had their spacesuits on and were ready, the astronauts would go outside and explore the lunar surface. In the case of Apollo 11, the two astronauts explored for about three hours before getting back in, taking a nap, and flying back up to their astronaut colleague in orbit. In order to do this, the LEM would actually split in half, leaving its legs on the Moon’s surface. The top half, lifted by a small booster engine, would then rendezvous with the Command Module orbiting in wait above them.
Once reconnected to the Command Module, the astronauts would unload the Moon rocks they collected and jump back in the Command Module. Just before heading back to Earth, they would detach what was left of the LEM and let it crash into the Moon, like leaving your canoe to drift on the lake if you don’t want to bring it all the way back with you. (Please don’t actually do that with your canoe though. Littering isn’t cool.)
The Astronauts
Who would NASA need to take on this mission? They decided that each Apollo mission would need three astronauts: one person to fly the Command Module, one person to fly the LEM, and an overall mission commander. The Command Module pilot would be the “unlucky” one who didn’t get to go down to the Moon. Instead, they would stay in orbit flying above the Moon while the other two went down in the LEM. The first Moon landing was accomplished by three astronauts on the Apollo 11 mission: Neil Armstrong, Buzz Aldrin, and Michael Collins. You’ll hear a bit more about them throughout the rest of the book.
Practicing for the Moon
The success of Apollo 11 didn’t come out of nowhere. Just like learning to do anything difficult, NASA took incremental steps in achieving the Moon landing.