Of course, in the past three years, although human civilization has been making every effort to build the Earth Defense circle, there is still a long way to go before the construction of the whole Earth Defense circle is completed, because according to the plan of the Earth Defense headquarters, not to mention others, only the earth low earth orbit defense facilities, that is, the space station with a tonnage of more than 500 tons, After completion, the number will exceed 5000.


    This is only a space station in low earth orbit. In addition, there will be more than 1000 military space stations in medium earth orbit with a tonnage of more than 500 tons, and more than 100 large military space stations in high orbit and geostationary orbit.


    So now it seems that they have built many large space stations, but compared with the whole plan, this is only the beginning. According to the plan of the Earth Defense Command, so many space stations and earth civilization will be built within the next six months. Therefore, such pressure is still very great for the whole human civilization.


    Of course, in addition to the construction of defense facilities outside the earth, the construction of ultra long-range defense facilities on the earth has not fallen behind. However, due to the limitations of human civilization and science and technology, only beam energy weapons, such as lasers, are available for ultra long-range attack weapons, especially those from cosmic threats.


    In addition, only those super large rockets that can launch deep space exploration spacecraft also have certain attack capability.


    Therefore, since the establishment of the Earth Defense Command three years ago, the whole world and the whole human civilization have also seen a thriving situation. Except for the uncivilized areas on the whole earth, wars have been basically eliminated in other areas, because we all know that compared with the threat of alien civilization and the huge interests in the universe, This tiny benefit on the earth can''t get into their eyes.


    What''s more, if someone in the whole Earth Defense Command Center dares to launch a war on earth, his voice in the Earth Defense Command Center will be weakened. Even being replaced by others is something they absolutely don''t want to see. You know, it''s related to their future development and interests.


    Such huge and numerous projects have naturally greatly stimulated the earth''s economy. Most companies make a lot of money, including Tiangong technology.


    Because Tiangong technology is the most advanced enterprise in aerospace technology on the whole earth, naturally many products are unique and indispensable. For example, the pulse detonation rocket engine of Tiangong technology is one of them. If there is no pulse detonation rocket engine of Tiangong technology, then, In the past three years, there will not be so many space planes on earth, and many space stations in natural earth orbit can not be built.


    In addition, there are some materials of Tiangong technology, especially special high-temperature resistant glass, which is also one of the necessary materials for manufacturing aircraft. Although many other space agencies on earth also have high-temperature resistant space glass, compared with this special glass of Tiangong technology, the performance of these space glass is far worse. Of course, they can be sold to their special glass, Tiangong technology or Huaxia is already very backward. They are the first generation products of sky technology. After all, the most advanced products can not be sold to them. Unless one day the whole earth civilization has been integrated into a big family, and there is no division between countries, at that time, Tiangong technology will naturally lift these restrictions, It''s just impossible now.


    Of course, at this time, the volume of multiple space stations in earth orbit is very large, so even the people on the ground can clearly see the existence of these space stations. Therefore, people on the earth have been used to the existence of these space stations, and people are more clear about the coming of the cosmic age, Therefore, even if the major in space has been expanded to 200% or more, but even so, the relevant majors in Colleges and universities are full year by year.


    At the same time, so many space stations, especially those affiliated to Tiangong technology and the official space station, look quite huge because the construction has been basically completed. Once at night, they hang in the sky like two night pearls.


    These two space stations are so huge that there are naturally few people working in these two space stations. Take the Ziwei space station of Tiangong technology for example. Although its total tonnage is only 1500 tons, there are thousands of astronauts living and scientific research in this space.


    In addition, people also see a little fire from time to time, close to these return stations, and then there is a fire to leave these space stations. It is very clear to everyone that these flashes of fire are the space plane to and from the space station, and the means of transportation between the earth and the space station.


    At the same time, in this era, it is quite convenient for people to travel in space. Just report to the official or Tiangong technology, and the price is also very cheap. The price for everyone to and from the space station is only a little more than 100000. It can be said that even ordinary people can afford such a price.


    In the past three years, according to Tiangong technology and official statistics, the number of people traveling to space in China alone has reached hundreds of thousands. It can be imagined how popular space tourism is today.


    Of course, this is only for China. If it is placed outside China, space tourism is not very easy, because at this time, the official side and Tiangong technology, all the aerospace aircraft have added up, and the number has reached more than 500, and it is mainly medium-sized aerospace aircraft, that is, Phoenix II series.


    You should know that the Phoenix series is not the Phoenix II series. Let alone the passenger operation of the Phoenix II series, the aerospace aircraft is only the original aircraft of the Phoenix II series, that is, the phoenix-kt2. With the crew at most, it can also carry 13 astronauts. This is still the Standard Version of the Phoenix II series.


    As for the passenger space plane of Phoenix II series, its maximum passenger capacity can send more than 100 astronauts to the space station at one time and then pick up more than 100 astronauts from space, which is absolutely unmatched by other space agencies in the world.


    Although in the past three years, other space agencies in the world have successively developed their own space shuttles after purchasing the pulse detonation rocket engine of Tiangong technology, most of them are cargo type space shuttles. Even one or two have developed passenger type space shuttles, but due to their own technology and other reasons, Its maximum passenger capacity can only carry 20 or 30 astronauts at one time. Thank God.


    In addition, the Phoenix II series of aerospace aircraft can reach the medium and high orbit space station, while the Phoenix series and the aerospace aircraft they developed can basically only be used for the round-trip of the medium and low orbit space station. So the gap between them and China is still very huge.