Special Chapter The Distance From Thoughts to the Starry Sky (Part 2)

"Actually, if it's just exploration, it actually started when the first satellite was launched."

Sitting around a campfire on a mountaintop like an isolated island in the sky, under the majesty of the Milky Way, when Fangran asked, Krim smiled and replied,

But I guessed that the "exploring the universe" he was talking about should be to the extent of interstellar navigation, and he smiled helplessly and shamelessly:

"But if it refers to what you think of Fangran, it is probably impossible to realize it within a few centuries under the foreseeable future development, and the follow-up time cannot be predicted."

After hearing his strict answer, Fangran nodded and asked very simply and straightforwardly:

"Is it because we can't build a spaceship?"

"Hahaha, that's right."

Hearing this, he couldn't help laughing. Krim raised his head and looked up at the prosperous starry sky above his head. Even though he had several astronomical observation activities,

But it was also the first time for him to see such a clear and beautiful Milky Way with his own eyes.

"But in the final analysis, we still know too little about the universe and there are too many unknowns. As a result, we don't even have theoretical knowledge until we can figure out whether to create something or not."

“And in the face of its hugeness, the small ones are helpless.”

Speaking of this, Krim lowered his head to look at Fangran and chuckled, telling a little about the hugeness.

"In the theory of relativity, the speed of light is the limit of the speed of the universe, but the size of the Milky Way is measured in one hundred thousand light-years, and the local group of galaxies it belongs to is measured in millions of light-years,"

"And above that there is the Virgo Supercluster, as well as the higher-level Laniakea Supercluster, and other superclusters of the same level."

At the same time, I also looked at the bonfire in front of me and expressed my insignificance.

"But now we don't even have a theory of a vehicle that can reach the speed of light, let alone go to the nearest star a few light years away,"

"Even activities within the solar system are difficult to achieve."

Fangran was in a daze as he listened. He barely knew about the Andromeda Galaxy, and this was the first time he knew about the existence of the name of the superior of the Milky Way Galaxy in the universe.

On the scale of one hundred thousand or one million light years, countries, economies, earthquakes, races, cultures... everything seems to be small compared with the astronomical distance.

"Is it because no one studies it?"

Every time when chatting with Kerim, Fangran would be troubled by his lack of knowledge and unable to ask any decent questions.

But perhaps because of this, he enjoyed chatting with Krim.

"It is mainly limited by the current level of scientific theory, but there are also some complicated reasons in this regard,"

In response to Fangran's curiosity, Klim still responded with a smile, and then continued to explain softly and gently:

"The research and development of science and technology needs a purpose. The emergence of rockets during World War II made major powers feel a sense of military crisis, so they competed for talents in the form of a space race,"

"The aerospace technology during that period advanced by leaps and bounds. The end of the Cold War naturally slowed down the pace greatly, and more people focused on research in other fields."

Just as Fangran liked chatting with him, he also liked such small talk. Compared with knowledge being used as a tool,

The curiosity answered by his most precious friend pleased Krim even more.

“After all, global resources have not yet been fully exploited and utilized, and have not yet developed to the point of considering space navigation. Due to multiple factors such as politics, capital, and productivity,

"

“This field is still in the process of development and exploration by humans under the premise of social affluence.”

Speaking of this, seeing Fangran's confused expression of "oh, oh, oh," Krim chuckled at him and added:

"If aliens appear one day, or if the earth's life hangs on a thread and we need to seize the life-saving straw of spaceflight, we may soon be able to enter the era of interstellar navigation."

"No, I always feel that I may not survive that time..."

Hearing Krim's 'comfort', Fangran spoke helplessly, but soon he looked up at the beautiful Milky Way above his head and laughed again.

There was no disappointment at all, but instead a voice of joy and anticipation.

"Isn't space navigation still unrealistic..."

"Although it is still far away from the deep space level, there are still some relatively realistic ideas at the near-Earth distance."

Also sitting on the tree stump, playing with the bonfire with branches, Li Ze, who had been listening quietly, spoke at this moment. Fang Ran, who was suddenly curious, swung his upper body forward and asked curiously:

"Hey! More realistic? What is it?"

"Like the space elevator."

"Space elevator?"

Hearing Li Ze's answer, Fangran's mind first came to mind about the 'giant metal pillar' that he had seen in any work, and he spoke with curiosity shining in his eyes:

"Isn't this thing made up in movies and TV shows? Is it very useful?"

"Very useful..."

After repeating what Fang Ran said, Li Ze thought for a moment before speaking slowly:

"It should be said that it has an epoch-making effect."

Knowing Fangran's level better, Krim gave him a more detailed explanation.

"With the current level of aerospace, the most troublesome thing about entering space is overcoming the earth's gravity. For this reason, most of the rockets are fuel for acceleration, and there are very few parts that carry cargo and people,"

Recalling the paper materials he had read before, he gave a simple and clear example:

"It costs about 20,000 US dollars to transport one kilogram of payload into space, even if it is very economical, and it costs at least one million US dollars to transport one person,"

"But if there is a space elevator, the price can be reduced to one percent, of course, not counting the cost of the elevator itself."

Eh! ? so cheap?

While surprised by this, Fangran heard Li Ze say something more profound.

"A simpler way to enter space means that people can transport resources more easily, build space bases more easily, and acquire knowledge and theories about space more easily,"

“The first step towards realizing humanity’s departure from the cradle.”

Listening to their explanation, I looked at the starry sky above my head and imagined a building that stretched straight into the sky. People could sit on it and reach straight into space.

Fangran looked at Rize and Klim, feeling incredibly surprised and asked:

"Is this really realistic? If it reaches space, how much weight does such a tall building have to have, and how much support does it need to be able to stand on the ground?"

"No, the design theory of the space elevator does not require ground support. Like the synchronous satellite, it relies on the gravity of the earth and the inertial centrifugal force in the synchronous orbit."

"Eh?"

Hearing Fangran make such a sound, he knew that he must not understand. Li Ze opened a projection on the campfire surrounded by three people, and drew two nested circles on it with his fingers, giving him the basis of a simple graphic explanation. principle.

"Assume that the perspective is above the North Pole, this circle is the Earth's equator, and the outer circle is the synchronous orbit."

"A synchronous orbit is an object in this altitude orbit. Because it is subject to equal gravity and centrifugal force, it will maintain a relatively stationary orbit with the earth."

I know this!

Regarding Krim Science's concern, Fangran let out a stubborn cry in his heart that he had not forgotten all about high school physics...