The Moon is the closest celestial body to the Earth, from which it is on average 384,403 km away. The first probe sent to the Moon was the Soviet Luna 1, launched on January 2, 1959. Ten years and six months later, the Apollo 11 space mission took Neil Armstrong and Edwin "Buzz" Aldrin to the Sea of Tranquility on July 20, 1969. Going to the moon is a feat that, to paraphrase John F. Kennedy, requires the best of a person's energy and skills.
Steps
Method 1 of 3: Plan your trip
Step 1. Plan to travel in stages
Despite single-stage space rockets popular in science fiction stories, going to the Moon is a mission that is best divided into several parts: reaching low Earth orbit, moving from Earth to lunar orbit, landing on the Moon, and finally, reverse the steps to return to Earth.
- Some science fiction stories that represented a more realistic approach to reaching the moon showed astronauts going to an orbiting space station, where smaller rockets were moored, which would take them to the moon and then back to the station. Due to the competition that existed between the United States and the Soviet Union, this approach was never adopted; the satiation stations Skylab, Salyut and the International Space Station were all created after the end of the Apollo Project.
- The Apollo Project used the three-stage Saturn V rocket. The first stage, the lower one, took off the entire vector from the launch pad up to the height of 68 km, the second pushed it almost to low earth orbit, while the third took it to orbit and then to the Moon.
- The Constellation Program, proposed by NASA to return to the Moon in 2018, consists of two different two-stage rockets. There are two different projects for the first stage of rockets: one dedicated to the launch of the crew and which consists of a single five-segment thruster, the Ares I, and another, the Ares V, for launching the load and crew, consisting of five rocket engines placed under an external fuel tank, supplemented by two five-segment solid fuel rockets. The second stage of both versions uses a single liquid fuel power unit. The carrier dedicated to the transport of heavy loads should carry the lunar module, where the astronauts would transfer to the docking of the two rockets.
Step 2. Pack your bags for the trip
Since the Moon has no atmosphere, you have to carry oxygen with you so that you can breathe when you are there; then when you go for a walk on the lunar surface you must have a spacesuit to protect yourself from the blazing heat of the lunar day, which lasts two weeks, or the mind-numbing cold of the equally long lunar night - not to mention the radiation and micrometeorites to which the surface is exposed from the absence of atmosphere.
- You'll also need something to eat. Most of the food consumed by astronauts during space missions must be freeze-dried and concentrated to reduce weight, and then rehydrated when it is eaten. It must also be high-protein food, so as to minimize the amount of body heat generated after the meal. (You can at least swallow it with the Tang, a fruit-flavored drink.)
- Everything you carry with you into space increases the weight, increasing the amount of fuel needed to get the rocket off the ground and travel into space, where you won't be able to carry too many personal belongings with you - and those moon rocks, on Earth, will weigh six times. more than on the moon.
Step 3. Establish the launch window
A launch window is the period of time during which the rocket must be launched from Earth for it to land in the intended area of the Moon when there is enough light to explore the landing area. The launch window has been classified into two types: monthly and daily.
- The monthly launch window takes advantage of the position of the zone in which the landing is expected relative to the Earth and the Sun. Since the Earth's gravity forces the Moon to always face the Earth the same face, the exploration missions were chosen in zones of the side facing the Earth, to make radio communications between the Earth and the Moon possible. The period also had to be chosen at a time when the Sun illuminated the landing area.
- The daily launch window takes advantage of launch conditions, such as the angle at which the spacecraft will be launched, the performance of the rockets and the presence of a ship to monitor the advance of the rocket during flight. In the early days, light conditions during launch were important, because daylight made it easier to monitor mission disruptions during launch or after reaching orbit, as well as documenting them with photographs. After NASA gained more experience in controlling missions, daytime launches were no longer necessary; Apollo 17 was in fact launched during the night.
Method 2 of 3: On the Moon or Death
Step 1. Take off
Ideally, a rocket headed for the Moon would have to be launched vertically to take advantage of the help that Earth's rotation would provide to reach orbital speed. In the Apollo Project, however, NASA considered a radius of 18 degrees in each direction from the vertical, without the launch being significantly impaired.
Step 2. Reach low earth orbit
In escaping the gravitational pull of the Earth, two speeds must be considered: the escape velocity and the first cosmic velocity. The escape velocity is that necessary to completely escape the gravity of a planet, while the first cosmic velocity is that necessary to enter orbit around a planet. The speed of escape from the Earth's surface is approximately 40,248 km / h, or 11.2 km / s. The first cosmic speed for the surface of the Earth is only about 7.9 km / h; it takes less energy to reach the first cosmic velocity than the escape velocity.
Furthermore, the further you get away from the surface of the Earth, the more the values of these two velocities decrease, and the escape velocity always corresponds to about 1,414 (the square root of 2) times the first cosmic velocity
Step 3. Switch to a translunar route
After you've reached low Earth orbit and verified that all vehicle systems are working, it's time to fire up the thrusters and go to the moon.
- In the Apollo Project, this was done by firing the thrusters of the third stage one last time, to propel the spacecraft towards the moon. Along the way, the Command and Service Module (CSM) separated from the third stage, capsized and docked at the Apollo Lunar Module (LEM), which was carried to the top of the third stage.
- In the Constellation Program, the project calls for the rocket carrying the crew and its command module to dock in low Earth orbit, with the starting stage and the lunar module carried by the rocket to dispatch the load. The starting stage should then fire up its thrusters and send the spacecraft to the moon.
Step 4. Reach the lunar orbit
After the spacecraft enters lunar gravity, fire up the thrusters to slow down and place it in orbit around the moon.
Step 5. Switch to the lunar module
Both the Apollo Project and the Constellation Program host distinct orbital and landing modules. For the Apollo command module, it was necessary for one of the three astronauts to stay behind to fly it, while the other two were aboard the lunar module. The orbital module of the Constellation Program, on the other hand, is designed to operate automatically, so that all four astronauts, for whose transport it was designed, can stay aboard the lunar module if they wish.
Step 6. Descend to the lunar surface
Since the Moon is devoid of atmosphere, it is necessary to use rockets to slow the descent rate of the lunar module to approximately 160 km / h, to ensure a smooth and damage-free landing for passengers. Ideally, the intended landing surface should be free of large rocks; this is why the Sea of Tranquility was chosen as the landing area for Apollo 11.
Step 7. Explore
After you've landed on the moon, it's time to take that little step and explore its surface. During your stay, you can collect samples of rocks and lunar dust for examination on Earth, and if you have brought a collapsible lunar rover like in the Apollo 15, 16 and 17 missions, you can also run around the surface at 18 km / h.. (Don't worry about revving the engine; the unit is battery powered, and there is no air to carry the noise of a packed engine anyway.)
Method 3 of 3: Return to Earth
Step 1. Pack your bags and go home
After you've done your business on the moon, pack your samples and tools, and board the lunar module for the return trip.
The Apollo lunar module consisted of two stages: one of descent to land on the Moon and one of ascent, to bring astronauts back into the lunar orbit. The descent stage was abandoned on the moon (as was the lunar rover)
Step 2. Dock at the orbiting ship
Both the Apollo command module and the orbital capsule were designed to bring astronauts back from the moon to Earth. The contents of the lunar modules are transferred to the orbital ones, and the lunar modules are then removed from the moorings, to then crash them on the Moon.
Step 3. Set course for Earth
The main thruster of the Apollo and Constellation service modules is turned on to escape the gravity of the Moon, and the spacecraft is directed towards Earth. Upon re-entering Earth's gravity, the service module's thruster is pointed at Earth and fired again to slow the descent of the command capsule, before being discharged into the sea.
Step 4. Prepare for landing
The command module heat shield is exposed to protect astronauts from the heat of reentry. As the ship enters the densest part of Earth's atmosphere, parachutes are employed to slow the capsule further.
- In the Apollo Project, the command module fell into the ocean, as it had done in previous NASA manned missions, and was recovered from a Navy ship. Command modules were not reused.
- The Constellation Program, on the other hand, provides for landing on the ground, as happened in Soviet space missions, where ditching in the ocean was an alternative in case it was not possible to touch land. The command capsule is designed to be reset, by replacing the heat shield with a new one, and reused.
