Scientific data of nine stations in interstellar travel deep space.

In order to escape from the earth, the speed of a spaceship must exceed 25, miles per hour. At a speed of 25, miles per hour, it will take the spacecraft 1 billion hours to reach Alpha Centauri-the total transportation time is 114, years. The idea of designing a self-sufficient human migration team that can successfully sustain itself for more than 1, years is terrible. It needs faster speed.

Even at the speed of light, it will take four years to travel to Alpha Centauri, but we have good physical reasons to think that it is impossible to approach this speed. Sebastian von Hellner thinks that 3% of the speed of light is the maximum speed we can expect, that is, 22 million miles per hour. At this rate, it will take 14 years to travel from Earth to Alpha Centauri. It takes five generations to travel. Some people may think that the progress of technology in the future can shorten the transportation time; But on the other hand, what if Alpha Centauri has no imaginary planet suitable for human life? In this case, our may flower spacecraft will have to "set sail" again, and it may be another five generations before its passengers are expected to find a new earth. Don't think that may flower spacecraft can be self-sufficient through ordinary agriculture, just like the earth. Sunlight can only make the green plants on the spacecraft grow in the first few months of the trip. Long before the spacecraft flew to Neptune, sunlight was not enough for photosynthesis, and everyone knew how dim distant stars were. In the dark, plants should inhale oxygen, just like animals do all the time. So plants will compete with humans for oxygen long before they get close to Neptune. Since Alpha Centauri is the nearest star, it means that most of the 14-year travel will be accompanied by starlight. There is no doubt that this is very romantic, but it is not very nutritious. It is necessary to use the energy on the spacecraft to regenerate oxygen. From what channels can the members of the immigrant team get the energy they need to live in the dark for five generations?

Freeman Dyson suggested that travelers can drop hydrogen bombs one after another at the tail of the spacecraft and capture 1% of the energy by using the barrier between the spacecraft and the explosion. Obviously, there are many engineering details to be solved before our spaceship leaves! The mobile migration team needs a safe way to store and use energy for 14 years. The savings and donations that our ancestors used to pay for the historic may flower trip to America can be expressed as the number of years of hard work needed to accumulate the necessary capital. Dyson believes that it takes one person 7.5 years' labor to pay for a family's travel expenses during the journey of may flower bringing the Puritans' predecessors to North America. For the historic trip of Mormons from Illinois to Utah in the 19th century, he calculated that each family needed to spend 2.5 people's annual income. For a well-designed space migration team project, he estimated that the cost of each family was 1,5 people/year. If we assume that there are four people in each family, it means that everyone has to pay for space travel with 375 years of labor income.

when we use the basic term of the number of years of working people to express the travel expenses, it is obvious that almost no passenger can afford his travel expenses. A person who works for 5 years in his life (from 15 to 65) ends up working for only 5 years, and consumes most of this amount in the course of his life. It is not easy to tell how much he can accumulate, but it is certainly not much. Therefore, every imaginary immigrant on the spaceship must be supported by a large group of people who stay on the earth. This scientific fact clearly calls for some generosity of the political system.

although the dollar is not the basic measure compared with the number of years of work, we will also gain something by roughly expressing the travel expenses in dollars. Consider the situation of a nuclear submarine. This is an elaborate mechanical device, but it is obviously not as complicated as a spaceship capable of 14 years of interstellar travel. A typical nuclear submarine costs $1 billion and carries 14 sailors. The boarding fee for each sailor is $7 million (we also ignore a considerable amount of operating costs). If every sailor has to buy his position on a submarine (just as British gentlemen in the 19th century had to buy their qualifications in an official agency), can an ordinary person earn enough money to pay the boarding fee before he is too old? It is rare that an ordinary person can save $1, a year from an ordinary job. With this optimistic savings rate, it will take him 7 years to accumulate the required boarding fees.