Vol 2 Chapter 122: On the third moon

At about 11.30 am on June 24th.
Here is the space port area of ​​the Tiangong space station. Here, the spacecrafts Houyi and Chang'e have completed restoring and refilling. All the materials that need to be reloaded have been installed. The huge hatches are closed slowly. Quietly waiting for instructions to go to the moon.
"Flight around the ground ~"
Soon, the instructions from the ground command and control center were transmitted to the two spacecraft and the 'Tiangong' space station.
The robotic arms holding the two spacecraft slowly released, and the two spacecraft began to slowly leave the space station and began to fly around the earth in orbit.
The reason why we chose to fly around the ground instead of directly choosing the direction of the moon was to fly past, which involved the issue of the initial speed of the spacecraft.
The distance between the earth and the moon is between 360,000 kilometers and 400,000 kilometers, with an average distance of 380,000 kilometers. Such a long distance is definitely the farthest place human beings have ever set foot on.
Because the distance is too far away, the spacecraft must get enough speed to do it, otherwise it will take too long, which is a test for the materials and astronauts carried on the spacecraft.
Flying around the earth, relying on the gravitational pull of the earth, the orbit of the spacecraft flying around the earth is an elliptical orbit. The speed is slow when it is near, and fast when it is far away.
Because you can rely on the gravity of the earth to give the spacecraft a good initial speed, it can greatly reduce the energy consumed by the spacecraft to accelerate.
The ‘Houyi’ and ‘Chang’ spacecraft are constantly orbiting the earth above the Earth ’s orbit. Through the adjustment of the orbits, the speed of the two spacecraft is also getting faster and faster.
"Fly to the moon ~"
When it was 12 o'clock, the order from the ground command center was transmitted again.
The Houyi spacecraft also just flew to the orbital apogee at this time, when the fastest speed,
"Boom ~"
The auxiliary fuel propulsion system on the 'Houyi' spacecraft began to work. A bright tail flame was ejected from the back of the spacecraft, and it continued to stretch in space, and soon became a long tail.
Driven by the assistance of the auxiliary power system, the 'Houyi' spacecraft got rid of the gravity of the earth very smoothly and speeded toward the moon.
At this time, with the help of the gravitational force of the earth, it gained a good initial speed, a speed of 20 kilometers per second.
If you fly to the moon at this speed, it will take about 6 hours to reach the moon.
However, the speed of the spacecraft is still not enough. The fuel propulsion system on the spacecraft is still constantly injecting flames, slowly accelerating it, and it will stop working when the speed reaches 40 kilometers per second.
Behind the Houyi, the spacecraft Chang'e soon got rid of the restraint of the earth's gravity in the same way, dragging its long tail toward the moon.
The speed of the two spacecraft is still accelerating. After half an hour, their speed reached the set speed of 40 kilometers per second, the auxiliary power system was turned off, and the spacecraft began to fly toward the moon in the void by inertia. .
The most energy-consuming part of flying in interstellar space is the two phases of acceleration and deceleration. The middle period of time and distance can consume almost no energy, and only rely on inertial flight.
The reason why the two spacecraft stopped accelerating after accelerating to a speed of 40 kilometers per second is also very profound.
According to Einstein's formula for mass energy, we all know that the faster an object is, the greater its ability to carry it. In reverse thinking, the faster you accelerate an object, the more energy it consumes. .
After the speed of the spacecraft reaches 40 kilometers per second, if you continue to accelerate it, the energy it consumes will become larger and larger, and the effect will become smaller and smaller.
It is likely to consume 1 unit of energy, and its speed can only increase a little, which is very uneconomical.
More importantly, when you are about to reach the moon, you also need to slow it down. The faster this speed is, the more energy it will consume when decelerating.
Therefore, after comprehensive consideration and calculation, scientists have fully considered the energy carried by the spacecraft, and the speed of 40 kilometers per second is most suitable.
In the vast and vast cosmic void, the 'Houyi' and 'Chang' spacecraft are like two small fireflies constantly flying in the endless void.
Although their speed is already very fast, nearly 40 kilometers per second, this is definitely the fastest speed of human beings at present, and this speed can only be achieved in the environment of space.
But compared to the vast expanse of the universe, the two spaceships seem to have remained at the same origin without any movement.
When you are in the vast starry universe, you even have the illusion that you seem to be still and stay on a point.
No matter if I look at it from that place, there seems to be no change. The starry sky or the starry sky is dark, dim, and the stars are bright. The road ahead seems to be endless.
Only when I look back at the earth every half an hour later, I can see that the earth seems to be slowly becoming smaller, and the moon in front is slowly becoming larger in view.
The two spacecraft stopped accelerating, and the astronauts on the spacecraft went to sleep.
They need to maintain a vigorous energy and physical strength. The process of inertial flight takes several hours, and they just can take a good sleep.
On the moon, exciting moments will come. More importantly, there are many tasks waiting for them. By then, it will not be so easy.
These astronauts usually have special training, saying that they will soon go to sleep one by one if they go to sleep. If they change to an ordinary person, it is estimated that they can't sleep at this time.
Because the moon is gradually growing in the field of vision, emitting a bright light, fascinating, the earth behind it, at this time also emits a bright light, very beautiful.
There is no temporary interruption of the astronaut's rest on the ground control command side of the earth. The automatic control system on the spacecraft keeps in touch with the side of the earth. When the time comes, someone will naturally remind you to wake the astronaut and start to enter the nervous. Moon landing phase.
Qin Yi is a bit boring. When the spacecraft inertia flies, there is nothing at all, and it is the safest time.
After thinking about Qin Yi returning to his dormitory and preparing for a nice nap, many scientists, engineers, and so on are now planning the same as Qin Yi.
Astronauts in space need to maintain a vigorous energy, and these scientists and engineers are the same, because scientists and engineers must be busy when they really land on the moon, and now they need to take time to rest well.
Qin Yi returned to his dormitory, habitually took out his mobile phone and prepared to see if there was anything on the company's side. There was nothing on the company's side, but Wen Xueying sent a lot of missing messages.
Qin Yi saw the message and was full of happiness. After thinking about it, a love poem emerged and sent back.
Is preparing to turn off the mobile phone for a nap, a message popped up on WeChat, no accident was the news of this manned landing on the moon.
The TV station broadcast live throughout this time. It was boring during the time of inertial flight, so I also invited a few experts and scholars to start playing their role and began to popularize some knowledge of cosmic interstellar space.
Qin Yi clicked in and began to look up with interest.
"Everyone now sees that the auxiliary power systems of the Houyi and Chang'e spacecraft have been shut down and have begun to fly by inertia in space."
"In space, because there is no air, in theory, it does not have any friction, so relying on inertial flight is the most energy-saving stage."
"According to my calculations, the two spacecraft will rely on inertial flight for more than 2 hours, after which it will start to slow down."
"Why slow it down?"
"Because the moon ’s gravity is very small, of course, it ’s compared with the earth. Because the moon ’s gravity is small, once the speed is too fast, the moon ’s gravity cannot catch two spaceships. The moon passes by. "
"So manned landing on the moon is a really dangerous stage. Whether this can be captured by the moon's gravity is one. Once it is too fast and passes the moon, it will be bad."
"So the speed of the two spacecraft must be reduced to a certain level, enough to be captured by the moon's gravity, and this process will be very time-consuming."
"The moon ’s gravity is too small. Its escape speed is only 2.4 kilometers per second. Now the speed of the spacecraft is 40 kilometers per second ~ EbookFREE.me ~ It is conceivable that the slowdown of the spacecraft will take a long time. . "
"This is a very important key point ~"
"Okay, thank you Professor Zhang for sharing the knowledge for us. At first, I thought that it was enough to fly directly to the moon at this speed. Now it seems that there is still a lot of knowledge about the routes in the interstellar universe."
"Here is a request for expert Wang to share some of his views for us."
"Okay, in fact, Professor Zhang has already said a lot, and also said a lot. The most energy-saving way to navigate the interstellar universe is to use the largest possible celestial bodies, such as Earth, Moon, Mars, etc. Gravity of the mass celestial body accelerates and decelerates. "
"Why the wandering earth that has been popular in the past few years, why did you want to get closer to Jupiter in the process of wandering? In fact, it is to use Jupiter's huge gravity to obtain greater acceleration ..."
Qin Yi suddenly became interested after watching for a few minutes. Although the experts and professors invited to the TV station to give lectures are not wrong, it is good for ordinary people to popularize science and science. It can let ordinary people know and understand some universes. Knowledge of sailing.
But for scientists at the level of Qin Yi, there is no need to learn at all. Qin Yi is already familiar with these things.
"It's also very good. Give ordinary people more science and science, and increase everyone's space science knowledge. However, the content should be slightly guided. The main thing is to paint space as gold everywhere, so that it can attract more people Dive into interstellar space. "
"You can talk more about the resources and minerals on the moon, and interest is the biggest driving force ~"
PS: The first order is very important ~ Everyone comes to support Lao Niu ~~