Siheyuan: Originally I just wanted to be a little transparent

After hearing the good news from Lin Shengli, everyone immediately cheered!
Soon, the entire launch base became a sea of ​​joy.

After everyone's excitement calmed down a little, Team Leader Wang stood in front of the command center and said loudly to the excited people below:

"Comrades, the successful test launch of our Long March [-] carrier rocket marks a great step for our aerospace industry!"

"To celebrate and commemorate this great moment, all our comrades will come to the cafeteria tonight. We will hold a celebration banquet for everyone in the cafeteria."

"I know this. For our project, many comrades who usually like to drink have been giving up drinking."

"Tonight, the alcohol ban is lifted for everyone, and everyone can drink to their heart's content!"

"Of course, comrades who have missions tomorrow should drink less..."

After Team Leader Wang finished speaking, the people below burst into laughter, followed immediately by cheers like a roaring mountain and a tsunami.

Afterwards, Team Leader Wang walked to Lin Shengli and said to Lin Shengli: "Comrade Shengli, thank you for your hard work on our test launch mission this time."

"Lao Nie and Dean Qian are still waiting for you in the small conference room. You should hurry over."

Hearing this, Lin Shengli nodded and walked quickly to the small conference room in the base.

When Lin Shengli came to the small conference room, there were not only Mr. Nie and Dean Qian, but also several comrades on the satellite project.

"Lao Nie, Dean Qian..."

As soon as Lin Shengli entered the door, he greeted everyone inside one by one.

"Come, Comrade Shengli, sit here." Nie Lao smiled and pointed to an empty seat next to him.

Hearing this, Lin Shengli nodded, walked to the seat designated by Mr. Nie and sat down.

After Lin Shengli sat down, Mr. Nie introduced him: "Comrade Shengli, let me introduce to you. These are Team Leader Sun, the person in charge of the satellite project, and his colleagues."

With that said, Mr. Nie turned to the comrades in the satellite project and said, "Who is this? I guess I don't need to introduce it to you."

"Everyone has just witnessed the test launch of our launch vehicle, and everyone knows who this is."

Then, Mr. Nie turned his head again and continued to say to Lin Shengli: "Comrade Shengli, I specially called you here to express my congratulations to you and congratulate you on the successful completion of the launch test of our Long March [-] carrier rocket. "

"Now, I have some things that I want to talk to you about."

When Lin Shengli saw that the comrades from the satellite project were here, he knew that Mr. Nie must have come to him not only to express congratulations, but also for other things.

Therefore, Lin Shengli did not rush to answer the call, but quietly waited for what Nie Lao would say.

"Comrade Shengli, your entire R&D project team has done a great job on this launch vehicle project."

"The successful development of our Long March-[-] launch vehicle this time has not only filled the gap in our country's launch vehicles, but has also reached the most advanced international level right from the start."

"Let our aviation industry suddenly move to the forefront of the world."

"When I go back, I will definitely apply for awards for all the comrades in your project team."

"Especially you, Lin Shengli. It can be said that without you, Lin Shengli, our launch vehicle project would not have been successfully developed so quickly, and it would not have been possible to directly raise the technical level of the launch vehicle to the world's advanced level. to the extend."

"It can be said that your contribution to our launch vehicle project is the greatest!"

Lin Shengli was a little embarrassed to hear Nie Lao's compliments, so Lin Shengli quickly said humbly: "Nie Lao, the successful completion of our launch vehicle project is the result of everyone's concerted efforts and hard work."

"And as a member of the project, I only did what I was supposed to do. I really don't deserve your praise!"

Mr. Nie smiled and did not continue to dwell on this matter.

After all, everyone has a sharp eye on who has done what, and there will definitely be no shortage of credit given to whoever deserves it.

"Comrade Shengli, I believe you already know from Team Leader Wang that because of the test launch of our Long March [-], the development work of the satellite project has been suspended."

"As for this specific situation, Team Leader Sun will tell you."

When Lin Shengli heard this, he knew that this was the main topic of calling him today, so Lin Shengli straightened his body slightly and started to listen carefully.

After Nie Lao finished speaking, Team Leader Sun nodded towards Nie Lao and said to Lin Shengli: "Comrade Lin Shengli, I have actually heard of your name."

"Here, I would first like to express my congratulations to you on the successful completion of the test launch of your launch vehicle project."

Lin Shengli smiled and nodded in response to Team Leader Sun's congratulations, and then continued to wait silently for Team Leader Sun's next words. "Our satellite project was established after your launch vehicle project, when you went to Shenyang Steel."

"At that time, it was precisely because the superiors knew that your launch vehicle project had made a major breakthrough, and after careful study, they finally allowed our satellite project to be launched."

"Originally, according to the instructions from our superiors and our planning, the satellite we want to build this time is to ensure that we can go up, catch, listen, and see."

"Now, after your launch vehicle is successfully developed, this problem of getting up to speed has been completely solved."

"As for those who can catch and hear behind, our comrades are also working overtime to carry out scientific research. To achieve these two goals, it is probably only a matter of time."

"However, now there is only this last visible goal left. To achieve this, based on our current technical level, it may be very difficult."

After listening to Team Leader Sun's introduction, Lin Shengli thought about it in his mind.

According to records from various later generations, when we were developing satellites, the above did put forward four requirements for the functions that the satellite was to achieve.

What's going on here: It is to ensure that the satellite can be sent into space and that it can enter the predetermined orbit.

This problem has been successfully solved with the successful development of their Long March-[-] launch vehicle.

That one can catch it: refers to the tracking and measurement of the satellite after it is launched into space.

This main measurement method is based on radio observation and supplemented by optical observation.

At this stage, the radio equipment we can choose from includes monopulse radar, phase contrast interferometer, and Doppler speedometer.

Among them, the orbit measurement methods of the first two devices are relatively mature, but they are expensive and require high ground station construction.

The Doppler speedometer is low-cost, but its tracking accuracy and solution method are not yet stable.

However, there are also researchers on satellite projects currently conducting scientific research, so the problem is not that big.

And the third one is audibility: that is, people all over the world can listen to the broadcasts sent by our country’s satellites through ordinary radios.

As for the fourth visible: it refers to the ability for observers on the ground to directly see satellites operating in space with the naked eye.

Just like when we are on the ground, we can see the brightest morning star in the sky at night.

When Lin Shengli recalled various records about satellites, Team Leader Sun continued: "Comrade Lin Shengli, we came to see you this time because we want to confirm with you that our launch vehicle is used for If a satellite is launched, what is its maximum carrying volume?”

"It turns out that our satellite development work is based on the original idea."

"After all, this is the first time our country has developed a launch vehicle. We originally guessed that the carrying capacity might not be that large."

"So when we first designed the satellite, we didn't dare to go big."

"But now, after your launch vehicle is successfully developed, our original designs are no longer suitable, and our satellites have to be redesigned."

"In this initial design, we designed this satellite into the shape of a regular 200-hedron with a diameter of one meter and a total weight of no more than 72 kilograms."

"However, when we conducted demonstrations later, we found that even if we designed the satellite like this, the satellite was still too small. Whenever the weather conditions were not ideal, we still couldn't see the satellite. See the target.”

"According to our estimation using data calculation methods, the brightness of our satellite can only reach the brightness of a sixth-magnitude star."

"It is very difficult for people to directly observe satellites with the naked eye."

(The brightness of a star is closely related to its temperature. We can distinguish the different brightnesses between stars with the naked eye. Ancient people divided starlight into 6 levels according to the different brightness levels. 1st-magnitude stars The brightest, while 6th magnitude stars are the dimmest. The brightness difference between each magnitude star is 2.25 times, and the actual brightness difference between 1st magnitude stars and 6th magnitude stars is 100 times.)
"So, Comrade Lin Shengli, now that your launch vehicle has been successfully developed, we want to know what the maximum design specifications of our satellite can be achieved if we use our launch vehicle to launch satellites."

"Only by knowing this, can we redesign and modify our satellites based on this indicator."

After listening to Team Leader Sun's introduction, Lin Shengli also understood their purpose of coming to him this time.

Lin Shengli thought for a moment and said, "Team Leader Sun, as for the weight, you don't have to worry too much about it."

"After all, the flight thrust of our Long March [-] has reached [-] tons, and the carrying capacity exceeds five tons."

"The weight of your satellite during design, according to this value, you can control it yourself."

"As for this size, judging from the carrying conditions of our Long March [-], as long as our satellite is no larger than five meters in diameter, there should be no problem."

The five meters Lin Shengli mentioned refers to the main diameter of the satellite, not the diameter after the solar panels are unfolded. (End of chapter)