Here in the space port area of the 'Tiangong' space station, the 'Houyi' and 'Chang'e' spacecrafts have completed their rest and replenishment. All the materials that need to be loaded have been loaded, and the huge hatches are slowly closed.
Quietly waiting for instructions to go to the moon.
"Flying around the earth~"
Soon, the instructions from the ground command and control center were conveyed to the two spacecraft and the Tiangong space station.
The mechanical arms holding the two spacecrafts slowly released, and the two spacecrafts began to slowly fly away from the space station and began to fly around the earth's orbit.
The reason why we choose to fly around the earth instead of directly pointing in the direction of the moon involves the initial speed of the spacecraft.
The distance between the earth and the moon is about 360,000 kilometers to 400,000 kilometers, with an average distance of 380,000 kilometers. With such a long distance, this is definitely the farthest place that humans have set foot on.
Because the distance is too far, the spacecraft must gain sufficient speed, otherwise it will take too long, which will be a test for the materials carried on the spacecraft and the astronauts.
Flying around the earth, relying on the earth's gravity, the spacecraft flies around the earth in an elliptical orbit, with a slow speed at perigee and a fast speed at apogee.
Because you can rely on the earth's gravity to give the spacecraft a good initial velocity, it can greatly reduce the energy consumed by the spacecraft in accelerating.
The spacecrafts "Houyi" and "Chang'e" are constantly flying around the earth's orbit. Through the adjustment of their orbits, the speed of the two spacecrafts is getting faster and faster.
"Fly to the moon~"
When the time reached 12 o'clock, the order from the ground command center was conveyed again.
The 'Houyi' spacecraft has just reached the apogee of the orbit at this time. At its fastest speed,
"Boom~"
The auxiliary fuel propulsion system on the Houyi spacecraft began to work, and a bright tail flame was ejected from the back of the spacecraft, continuously elongating in space, and soon turned into a long tail.
With the help of the auxiliary power system, the 'Houyi' spacecraft successfully escaped the gravity of the earth and flew rapidly towards the moon.
At this time, with the help of the earth's gravity, it obtained a good initial speed of 20 kilometers per second.
If it flies towards 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 still sprays flames all the time, slowly accelerating it. When the speed reaches 40 kilometers per second, it will stop working.
Behind the 'Houyi', the 'Chang'e' spacecraft soon broke away from the shackles of the earth's gravity in the same way, dragging its long tail and driving rapidly in the direction of the moon.
The speed of the two spacecrafts continued to accelerate. 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 rely on inertia to fly towards the moon in the void.
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When flying in interstellar space, the most energy-consuming phases are the initial acceleration and final deceleration. This period and distance in between consume almost no energy, and you only need to rely on inertial flight.
There is a profound reason why the two spacecraft stopped accelerating after accelerating to a speed of 40 kilometers per second.
According to Einstein's mass-energy formula, we all know that the faster an object is, the greater its carrying capacity. Thinking conversely, the faster you accelerate an object, the greater the amount of energy it consumes.
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After the speed of the spacecraft reaches 40 kilometers per second, if you continue to accelerate it, the energy consumed will become larger and larger, and the effect will become smaller and smaller.
It is very likely that 1 unit of energy will be consumed, and its speed will only be slightly improved, which is very uneconomical.
More importantly, when you are about to reach the moon, you need to slow it down. The faster it 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 determined that the speed is most appropriate at 40 kilometers per second.
In the vast void of the universe, the spacecrafts "Houyi" and "Chang'e" are like two small fireflies flying continuously in the endless void.
Although their speed is already very fast, with a speed of nearly 40 kilometers per second, this is definitely the fastest speed currently achieved by humans, and this speed can only be achieved in the space environment.
But compared to the vast universe, the two spaceships seemed to have always been at the same origin without any movement.
When you are in the vast starry sky and universe, you may even have the illusion that you seem to be motionless and always at one point.
No matter where you look from, there doesn't seem to be any change. The starry sky is still a starry sky, dark, dim, with bright stars, and the road ahead seems to be endless.
Only when you look back at the earth every half hour, you will find that the earth seems to be slowly getting smaller, and the moon in front of you is slowly getting bigger in the field of vision.
The two spacecraft stopped accelerating, and the astronauts on the spacecraft also fell asleep.
They need to maintain strong energy and physical strength. The process of inertial flight takes several hours, and they can just have a good sleep.
When they reach the moon, exciting moments will come. More importantly, there are many tasks waiting for them, and it will not be so easy by then.
These astronauts usually have special training, saying that they fall asleep very quickly. If it were an ordinary person, they probably would not be able to sleep at all at this time.
Because the moon is slowly getting bigger in the field of vision, emitting a bright light that is fascinating, and the earth behind it is also emitting a bright light at this time, which is very beautiful.
The earth's ground control center did not disturb the astronauts' rest for the time being. The automatic control system on the spacecraft kept in contact with the earth. When the time was up, someone would naturally remind them to wake up the astronauts and start a tense period.
Moon landing stage.
Qin Yi was a little bored. Nothing happened when the spacecraft was flying inertly. It was the safest time.
After thinking about it, Qin Yi returned to his dormitory and prepared to take a pleasant nap. Many scientists, engineers, etc. also had the same plan as Qin Yi at this time.
Astronauts in space need to maintain high energy, and so do these scientists and engineers, because when they actually landed on the moon, scientists and engineers were just as busy, and now they also need to seize the time to take a good rest.
Qin Yi returned to his dormitory, and habitually took out his mobile phone to see if there was anything going on with the company. There was nothing going on with the company, but Wen Xueying sent many missive messages.
When Qin Yi saw the message, his face was filled with happiness. After thinking about it, a love poem emerged and he sent it back.
Just as I was about to turn off my phone and take a nap, a message popped up on WeChat. Not surprisingly, it was about the manned moon landing.
The TV station is broadcasting the whole process live. This period of relying on inertial flight is also very boring, so we also invited several experts. Scholars began to play their role and began to popularize some knowledge about the universe and interstellar space.
Qin Yi clicked in and began to read with interest.
"Everyone has now seen that the auxiliary power systems of the Houyi and Chang'e spacecraft have been shut down and have begun to rely on inertial flight in space."
"In space, because there is no air, theoretically there is no friction, so relying on inertial flight is the most energy-saving stage."
"According to my calculations, the two spacecrafts will probably fly by inertia for more than 2 hours, and then they will start to slow down."
"Why slow down?"
"Because the moon's gravity is very small, compared with the earth's, of course, because the moon's gravity is small, once the speed is too fast, the moon's gravity cannot capture the two spacecrafts, and the two spacecrafts are likely to catch up with each other.
The moon passed by."
"So the really dangerous stage of manned moon landing is whether it can be captured by the moon's gravity. Once the speed is too fast and misses the moon, it will be bad."
"So the speed of the two spacecrafts must be reduced to a certain level, low enough to be captured by the moon's gravity. This process will be very time-consuming."
"The moon's gravity is too small, and its escape velocity is only 2.4 kilometers per second. The current speed of the spacecraft is 40 kilometers per second. It can be imagined that it will take a long time for the spacecraft to decelerate."
"This is a very important key point next~"
"Okay, thank you Professor Zhang for sharing the knowledge with us. At first, I thought it would be 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 this interstellar universe."
“Now let’s ask expert Wang to share some of his views with us.”
"Okay, in fact, Professor Zhang has just said a lot. He also said a lot that the most energy-saving way to navigate in the interstellar universe is to make the most possible use of massive celestial bodies, such as the earth, the moon, Mars, etc.
It uses the gravity of massive celestial bodies to accelerate and decelerate.”
"The popular Wandering Earth in the past few years, why did it approach Jupiter first during the wandering process? In fact, it was to use Jupiter's huge gravity to gain greater acceleration..."
Qin Yi became interested after watching it for a few minutes. Although the contents of these experts and professors who were invited to give guest lectures on the TV station were all correct, they were popular science for ordinary people. The popularization of science is still good, and they can let ordinary people know and understand some of the universe.
Navigation knowledge.
But for a scientist of Qin Yi's level, there is no need to learn at all. Qin Yi is already familiar with these things.
"It's also very good. It can popularize science to ordinary people and increase everyone's space science knowledge. However, the content still needs to be slightly guided. The main thing is to depict space as gold everywhere, so as to attract more people.
Plunge into interstellar space.”
"You can talk more about the resources and minerals on the moon. Profit is the biggest driving force~"
ps: The first order is very important~ Everyone come to Qidian to support Lao Niu~~