Is interstellar travel possible? What technologies are available for interstellar travel?

Interstellar travel has always been a human dream, but as we all know, the existing technology and scientific and technological strength are not enough to achieve interstellar travel. After all, the fastest speed of mankind is only third cosmic velocity. It takes 4.2 years to travel to the nearest proxima centauri Centauri at the speed of light, not to mention the human chemical propellant spacecraft. Wouldn't it take tens of thousands of years to fly? Let's share with you what technologies can realize interstellar travel.

Whenever we describe something as extremely fast, we often compare it with a rocket-XXX is like the speed of a rocket.

In fact, the average orbital speed of launch vehicles is 7.6 km/s, and the highest speed can reach 10.8 km/s.

This speed is at least 65,438+0.26 times the driving speed of golf.

At least seven times the speed of a bullet,

Its speed is at least 3.7 times that of X- 15 rocket-powered aircraft in North America, but it is as slow as a turtle compared with the speed of light. The difference between the two is 40 thousand times!

After all, human beings often face a cosmic scale that spans light years.

You need to know how little space there is for human activities in space.

Voyager/KOOC-0/As the farthest aircraft of human beings, on August 26th this year, it was 2.08×/KOOC-0/0/0 km away from our earth, but it was a light-year (946×/KOOC-0/0/KOOC-0).

You know Voyager 1 has been flying for 39 years+165438+ 10 +2 1 day!

Therefore, breaking through the speed of the existing man-made aircraft can be said to be the dream pursued by N generations.

As the aerospace dynamics experts have concluded, at present, the chemically powered rockets are almost exhausted and the speed is almost over. Only by jumping out of the existing chemical power propulsion can we reach the space speed of science fiction.

Let's take a look at several future starships that are closer to reality and more reliable, and the super propulsion technology behind them.

Thermonuclear spacecraft thermonuclear population

As early as 1973, the British Interstellar Society, the oldest space exploration research institution in the world, formally put forward the concept of thermonuclear spacecraft.

In fact, the principle of propulsion is similar to that of our sun burning, which uses thermonuclear fusion to generate huge energy.

The key of thermonuclear power lies in controlled nuclear fusion technology. At present, there are mainly three kinds: ultrasonic nuclear fusion, laser confinement (inertial confinement) nuclear fusion and magnetic confinement nuclear fusion (tokamak type).

Laser confinement and magnetic confinement are the main directions, and the US Department of Energy focuses on laser confinement to develop nuclear fusion.

China, the European Union, the United States, Japan and Russia jointly invested 654.38+0.6 billion euros to build the world's largest experimental magnetic confinement nuclear fusion reactor ITER, which is mainly magnetic confinement and is expected to be assembled in 2065.438+09.

According to the research report of the British Interstellar Society, once human beings master the thermonuclear propulsion technology, the spacecraft will reach the space speed of more than 10000 kilometers per second, which is 1/30 of the speed of light, thus approaching the speed of light.

Laser plasma propulsion of laser spacecraft

Laser spacecraft, also known as pulsed laser propulsion spacecraft, uses high-energy and fast-repeated pulsed laser beams to heat propellant, that is, the working medium does not heat stably, but produces a series of huge pulse explosion waves.

When the propellant flows to the laser focal region, it will be heated up and ionized rapidly, become a high-temperature plasma and expand rapidly, forming an explosion wave supported by the laser, and then the explosion wave will be ejected from the supersonic nozzle to generate thrust.

It is reported that once the laser spacecraft technology is mature, its theoretical speed is about 1% of the speed of light, that is, 3000 kilometers per second.

This technology was developed by the United States and the Soviet Union as early as 1970s. The latest breakthrough is that in 2000, American Bareboat Technology Company launched a prototype laser spaceship with a diameter of 12.2 cm and a weight of 50 grams to a height of 7 1 m and flew for 12.7 seconds.

This is the record of the longest flying time, the highest flying height and the heaviest weight of the laser spacecraft so far, which is equivalent to the Wright brothers flying the plane into the blue sky for the first time.

Light sail light sail

Also known as solar sail, it uses huge thin-film lens and the radiation pressure of Ethernet sunlight as the propulsion of spacecraft.

The concept of light sail was first put forward by German astronomer Kepler in17th century.

In 20 10, Japan launched a test version of the space probe IKAROS. IKAROS, whose full name is "an interstellar kite accelerated by solar radiation" (also known as Icarus, a tragic figure in Greek mythology, whose flying wings made of wax flew to the sun and fell into the water and died), was developed by JAXA, a Japanese aerospace research and development agency, and was the first detector powered by solar sails in the world.

The "Guangfan 2" developed by the British Interstellar Association is expected to be launched into space for testing by Space Exploration Technology Company in 20 18.

Interstellar bus

Also known as Bussard ramjet powered spacecraft, it is a future space propulsion technology conceived by American physicist Bussard in 1960s. This propeller is a nuclear fusion ramjet, which uses a huge electromagnetic field (tens of thousands of square kilometers) as a funnel to collect and compress hydrogen in interstellar matter (because 75% of ordinary matter in the universe is hydrogen) until it is enough for nuclear fusion, thus pushing the spacecraft forward through reaction.

According to Bhusal's deduction, the maximum propulsion speed of this interstellar gas ramjet spacecraft will not exceed100 km/s. Although the flight speed is not fast, it has a long endurance and is suitable for interstellar flight.

Electromagnetically driven spacecraft

The principle of electromagnetic drive 1999 was first put forward by the British engineer Roger Sawyer.

The principle of electromagnetic drive is that in a conical cavity without a spire, a large number of electromagnetic microwaves are generated by solar power supply, and high-density back-and-forth reflections are formed in the conical cavity, and huge thrust is generated by using the thrust difference formed by the unequal thickness of the two ends of the conical cavity, thus promoting the flight of the aircraft. This is equivalent to generating propulsion in a closed container, but it does not need any chemical fuel propellant, and its scientific name is no working medium drive.

It is said that in February 16, 16, 10, China Academy of Space Technology announced an exciting scientific research achievement: the electromagnetic drive technology has been successfully tested in Tiangong-2, which means that the principle verification of this divine drive technology is not only feasible and reliable, but also will be developed as soon as possible, and it will be first applied to satellite propulsion.

You should know that this technology has been developed by NASA 10, and the American CannaeDrive company, which is bound to NASA's electromagnetic drive technology, plans to launch a 6U cubic satellite in 20 18, and then conduct space verification. China is likely to be ahead of American technology here, and take the lead in manufacturing a superb engine-an electromagnetic-driven space propeller.

Antimatter spacecraft

When matter and antimatter meet and annihilate, mass can be completely converted into energy, thus maximizing energy efficiency. According to calculation, the unit output of antimatter engine is trillion times that of conventional fuel/thousand times that of nuclear energy. Therefore, antimatter drive has always been the god-class propulsion technology that people dream of.

However, due to the current artificial way of making antimatter, we can only rely on accelerating particles to hit the fixed target to produce antiparticles, and then slow down the synthesis.

The energy required for this process is far greater than the energy released by annihilation, and the rate of antimatter production is extremely low, so it has no economic value at present. In addition, antimatter and matter will be annihilated when they meet, and preservation is also a big problem.

However, the development of antimatter engines has never stopped. Recently, American physicist Rad Jackson, who works in Fermilab, invented a recoil starter and is testing the antimatter propeller.

In addition, some researchers are studying more sci-fi spacecraft propulsion technologies, such as space curvature driven spacecraft.

Just like the Warpdrive in Star Trek and the curvature engine in Three-body, this spacecraft moves at top speed by shrinking the front space and expanding the rear space. It seems too mysterious, but it is feasible in theory, because it completely follows a set of space-time metrics established by Einstein's field equation.

What would it mean if any of these sci-fi technologies achieved a breakthrough?

According to my own understanding, this will bring about the second revival of human civilization and a complete leap of human society.

Because from now on-the global energy problem, as far as the future-space immigration and interstellar colonization essentially need a thorough energy revolution, which can only be realized by fundamentally upgrading the existing energy technology and space power technology, and these spacecraft equipped with future technology are the most promising frontier technologies for mankind.

What kind of spacecraft do you think is most suitable for human beings?