How difficult is it to colonize Mars? Scientists believe that the biggest problem in landing on Mars is energy.

Speaking of interstellar travel, this melody will definitely ring in everyone's mind. Yes, this is Interstellar, known as the strongest science fiction movie. The setting of the story background and the visual impact of the picture are very shocking. Many people are amazed after watching it, and some people ask if interstellar travel in the movie can really be realized.

First of all, we don't discuss the impulse in the film, but refer to the spaceship inside. When it comes to interstellar travel, many people will think of Musk's Mars immigration plan, which aims to use the interstellar spacecraft they developed to transport 654.38+million people to colonize Mars and build cities on Mars. However, although the goal looks grand, at this time, someone came out to attack that unless the problem of traditional chemical fuels is solved, human beings will never be interstellar immigrants. What's going on here? Today, let's learn about the energy of space flight! So I'm here to ask you a question: With the current rocket fuel, can we really land on Mars?

Why not say that unless we break through energy technology, human beings will never realize interstellar travel? Let's take a look at what energy is used in space science and technology at present. Energy is the energy that drives the spacecraft to fly. At present, the main energy source for space launch is chemical energy, that is, chemical fuel. For example, the mainstream launch vehicle in our country, cz-3, known as a model worker, uses unsymmetrical dimethylhydrazine and nitrogen tetroxide. Although Changsan carrier rocket is our meritorious rocket, it is named toxic, and the yellow smoke emitted during launch is nitrogen tetroxide residue, which is highly toxic and corrosive. Therefore, our country has developed the Long March 5 carrier rocket, which adopts a non-toxic scheme of combining liquid oxygen kerosene with hydrogen and oxygen, but it still can't get rid of using chemical fuels.

The disadvantage of chemical fuel is very obvious, that is, it consumes a lot. Let's take Saturn V of the Apollo program in the last century as an example. The total weight of Saturn V rocket is about 2290 tons, and the fuel alone reaches 2 160 tons, that is, it burns continuously at the speed of 13 tons per second 165 seconds. Saturn V, a big guy with a total weight of 3,000 tons, only sent 45 tons of load to the moon. Take Musk's starship again. If a starship wants to go to Mars once, it needs to refuel in low-earth orbit for 3-5 times, which is enough for it to enter the fire transfer orbit from low-earth orbit, and it must have enough fuel to slow down and land on Mars. Therefore, 1 10,000 people's dream of immigrating to Mars is difficult to realize.

So since chemical energy can't be done, what energy is feasible for future space flight? There is no doubt that the most likely thing at present is nuclear energy! Sun Zezhou, chief designer of Chang 'e III, once said: "From the perspective of technological development, it is unrealistic to rely entirely on solar energy to detect planets farther away from the sun like Jupiter in the future. During this period, there is a great demand for the application of space nuclear power. In the last century, both the United States and the former Soviet Union studied nuclear spacecraft, but both ended in failure. Although nuclear energy has been used on a small scale, such as nuclear power plants and nuclear power drives, it still cannot completely control nuclear fusion, which limits the development of nuclear spacecraft, and the most important reason is the fear of nuclear pollution.

Ion thruster, ion thruster is characterized by high specific impulse and high efficiency. At present, small ion thrusters have little effect and are widely used in various deep space detectors such as Hayabusa. At this time, some knowledgeable friends questioned that ion thrusters are ok for satellites and detectors, but they are not reliable for human interstellar travel. The United States once proposed a VASIMR rocket, the full name of which is a variable specific impulse magnetic plasma rocket. It is a high-power propeller of nuclear power and an electric rocket with both large thrust and high specific impulse. Although this kind of rocket also uses nuclear propulsion, there is no danger of nuclear pollution!

Generally speaking, nuclear spacecraft and ion thrusters can be broken through at present, so what about things that may be realized in the future and now look like science fiction? That's antimatter! It is feasible in theory that antimatter is used for human beings to travel across the universe to more distant deep space, but at present it is limited to theoretical and sci-fi works, and it is the favorite interstellar transportation fuel for science fiction writers. Using antimatter can accelerate the spacecraft to the maximum near the speed of light. But at present, the research on antimatter is still in the stage of discovery, and the production, preservation and use of antimatter are so far away now.