How long does it take for humans to build a spaceship?

The reason why human beings yearn for the speed of light so much is to realize all kinds of unattainable dreams through the speed of light, such as finding a time tunnel in the speed of light and realizing the desire to go back to the past or shuttle back to the future.

Or, with family or friends, travel in space in a light-speed spaceship, or use the light-speed engine to realize interstellar immigration, and so on. In a word, whenever we talk about problems related to the universe, we will always talk about the speed of light, because nothing can be separated from the speed of light if human beings want to realize the above dreams. This shows how important the speed of light is in people's minds.

However, it is difficult for people to approach or reach the speed of light, at least for now, this possibility is almost zero. According to scientists' theory, any substance with mass at rest, even a grain of sand or dust, can't reach the speed of light as long as they have mass. This is an iron law that has been "doomed", and countless scientists feel desperate before this iron law.

At present, the farthest space probe invented by human beings is Voyager 1, 1977 launched into space, and it still maintains a high speed of 6 10000 km. Although Voyager 1 has successfully flown out of the solar system, it will take another 56,000 years to reach the final target, Alpha Centauri.

If humans want to reach the vicinity of Centauri alive by spaceship, scientists need to build a spaceship that is 1 000 times faster than Voyager1. However, reality is always cruel. The speed of Voyager 1 is 6. 1 10,000 kilometers per hour, which is simply the difference between a snail and a rocket compared with the speed of 300,000 kilometers per second at the speed of light.

However, human beings want to fly at the speed of light, and the biggest resistance at present is the weight of the spacecraft. If a spacecraft wants to approach the speed of light, it must first have energy in proportion to the speed of light, and the chemical fuel carried by the spacecraft is extremely limited. We should not only consider the proportion of the spacecraft, but also consider whether the spacecraft loaded with a lot of fuel will explode and many other dangers.

Scientists, on the other hand, point out that according to calculations, if human beings want to reach 6% of the speed of light, they need chemical fuel equivalent to the entire solar system. So scientists have also come to the conclusion that it is absolutely impossible to fly at the speed of light only by oil or other chemical fuels.