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Meeting Point News In July, Branson, the boss of Virgin Galactic, successfully completed a suborbital flight and took a space trip on the company's plane. In the same month, Bezos, the founder of American Amazon, flew into space on the plane of American Blue Origin Company and completed a suborbital space trip.

How do humans "roam" in space?

Space tourism is based on people's ideal of traveling in space. Space travel provides people with an unprecedented experience. The latest and most exciting thing is that you can enjoy the beautiful scenery in space and enjoy the "taste" of weightlessness.

How to carry out space tourism, first of all, there must be a "spaceship" to send people into space. Such "operations" are not new. As early as April 28th, 20001year, American businessman dennis tito bought the "ship ticket" of the Russian Soyuz spacecraft and became the first tourist to visit the International Space Station. But for this "boat ticket", dennis tito spent more than 20 million dollars.

"Focusing on the two space trips in July, we found that although the time is close, Branson and Bezos have different launch ideas." Tang said that Blue Origin used the traditional manned spacecraft for suborbital space tourism, and launched the crew cabin with the new Shepard rocket (a recoverable rocket launching system). Its characteristic is that all planes take off and land vertically, and the time of one flight is about 10 minute. Virgin Galactic's plan is to launch the spacecraft-2 suborbital space shuttle in the air through the The White Knights-2 aircraft and send tourists into suborbital space. The plane takes off and lands horizontally, and the flight time is about 1.5 hours.

Due to the differences in aircraft and launch methods, the new Shepard suborbital spacecraft of American Blue Origin Company and the Spacecraft II suborbital space shuttle of British Virgin Galactic Company can be said to have their own advantages and disadvantages. Tang introduced that the British spacecraft can fly longer by adopting the new horizontal take-off and landing mode, while the new Shepard spacecraft adopts the traditional rocket vertical launch mode. Although the flight time is only 10 minutes, the flight altitude is higher and it is safer to carry the escape system. The waste discharged by aircraft is water, which has little effect on the ozone layer, while the propellant used in Virgin Galactic aircraft engine is 65,438+000 from blue source.

How high does it fly to be considered as "space tourism"

There are three ways to experience space tourism at present: suborbital flight, orbital flight and parabolic flight. It should be noted that the two "space trips" in July were both "suborbital flights", so what exactly is "suborbital flight"? Tang explained that all orbital flight paths are an "ellipse" around the earth. However, because the altitude and speed of suborbital aircraft can not meet the requirements of orbital flight, its flight trajectory is actually a parabola.

That is to say, suborbital flight means that the aircraft enters the space about 100 km above the ground, but it is not a flight around the earth more than once. If the aircraft flies more than once in the earth orbit above 300 kilometers from the ground, it is called orbital flight. Sub-orbital space tourism is to send tourists to the edge of space at a height of 100 km by sub-orbital aircraft, and then return to the ground immediately.

Only when tourists fly in orbit by plane can they really "travel in space". At present, the space tourism tool to realize orbital flight is mainly the International Space Station, and the shuttle vehicles for tourists to reach the International Space Station mainly include Russian Soyuz series spacecraft and American manned dragon spacecraft. Orbital flight allows space tourists to enjoy some novel experiences such as weightlessness and overlooking the earth, because space tourists can live in the spacious "International Space Station" for at least one week. Up to now, seven tourists have visited the International Space Station eight times to enjoy the orbital flight, which is extremely expensive, generally in the tens of millions of dollars.

The last kind of parabolic flight is not a real space tourism, but only allows tourists to experience weightlessness several times in space. Parabolic flight of weightless aircraft. Professional astronauts often use this method to experience weightlessness in training. If space tourists take the Russian Il -76 weightless plane, they can also experience the weightlessness that is difficult to simulate on the ground. When tourists fly to an altitude of about 18 km, passengers can see the curve of the earth below and the dark sky above, and experience endless emptiness. At present, some special fighters can be used to complete this kind of high-altitude mission, which can fly to a height of about 24 kilometers.

What can space tourism do?

What can suborbital space tourism do in a short time? "This is not so much a play as an experience." Tang explained that the current suborbital space tourism is more like an experience, just like riding a roller coaster. Although the time is short, it brings people an unprecedented experience. The same is true of space tourism. First, it can make people condescend to appreciate the beauty of the earth and look up at the bright starry sky in the universe under vacuum. Second, it can make people experience the magical feeling of weightlessness, floating freely in the cabin, and lifting weights as easily as possible.

"On the plane at an altitude of 10 km, you can see clouds and high sky. In the space at the height of 100 km, you can see the earth as blue as a gem, the atmosphere distributed on the surface of the earth and the deep starry sky. " Space tourism is attractive because it gives us a real chance to get in touch with space, which has different significance for people who have feelings for space.

Although examples of suborbital space tourism have appeared in front of us, Tang believes that it will take a long time for space tourism to be accepted by the public. How to reduce the cost of space tourism is very important, and there is still a long way to go to become an industry. Although the aircraft of the two companies can be recycled, they also have to bear huge costs such as recycling and maintenance. In addition, it is unknown whether the safety of reused and maintained aircraft is guaranteed, and the technology may need to be updated repeatedly.

Although the suborbital space tourism completed by Branson and Bezos is only an experiential test flight within the company, Tang thinks it is of great significance. Introducing commerce into the development of aerospace industry has its unique advantages. Can bear the cost of initial experiment failure, try again and again, and try more fields. "The first reusable orbiter was the space shuttle, but the space shuttle was not very successful in cost control and safety, and its painful lessons objectively hindered the subsequent attempt to reuse technology. However, Virgin Atlantic and other companies have re-used these technologies and developed new technologies, which has broken the impact of the space shuttle failure, which is worth encouraging. "

In Tang's view, folk space tourism can be expected in the future. According to the plan of China Long March Rocket Company, China's first civil space tourism project will be implemented before 2024 to realize short-distance suborbital flight. The ultimate goal is to build a long-distance tour group that can accommodate 10 to 20 people before 2035. "Space tourism is not a pure market or commercial issue, but actually an inevitable trend of the development of human society." Some experts also said that at present, China is dominated by commercial space activities, and there is no formal space tourism activity. In order to achieve greater development, China's sky tourism needs the promotion of social forces and market capital.

More news:

Why is flying over the "Carmen Line" considered as space tourism?

Kármán line is a line at an altitude of 65,438+000 km (330,000 feet), which is considered by most people as the dividing line between outer space and the earth's atmosphere. This line is accepted by the International Aviation Federation (the organization that formulates and keeps records of the International aerospace standards), and it is the current definition of the boundary between the atmosphere and space. Only when the flying height of the aircraft crosses the Carmen line can it really enter space.

This line is named after Theodore von Kármán, a Hungarian-born American engineer and physicist, who is mainly engaged in aviation and aerospace engineering. For the first time, he calculated that it was impossible to fly near this height. Near this altitude, the atmosphere is too thin to generate enough lift to support aviation flight. According to his calculation, the speed of the aircraft itself at this altitude must be much faster than the orbital speed in order to get enough lift to support its own weight.