Building a Dream "Paradise" | The International Space Station is aging, where is the future of the US space station going?
Recently, two pieces of news about the space station have aroused public attention.
The first one that everyone must have guessed is China's "space internet celebrity"-the "Tiangong" space station.
On April 29, the "Tianhe" core module was successfully launched. The core module is an important part of China's space station. According to the current plan, my country will continue to implement 11 missions in the future, and it is expected to complete the space station construction in 2022.
At the same time, the Chinese space station is also open to the world, and all countries are welcome to join. At present, many countries have submitted applications for stationing.
The other is about the International Space Station. On April 18, Russian Deputy Prime Minister Borisov told the outside world that in view of the serious aging of the International Space Station (ISS), the space station operation contract will also expire in 2024. Russia plans to start from 2025. Exit the project and proceed to build its own space station.
Analysis believes that the multifunctional experimental module of the "Science" that Russia will launch this year will be the basis for its future space station construction.
After the decommissioning of the International Space Station, where will the US space station go in the future?
Those things about the U.S. space station
During the crazy Cold War era, the United States and the Soviet Union competed and competed in almost every field, and the space station was no exception.
The Soviet Union, which was defeated in the manned moon landing race, shifted its focus to the space station and took the lead in launching the first manned space station in human history, the "Salute 1".
The first US space station "Sky Lab" was launched two years later than the Soviet Union's "Salute 1". In fact, the US space station program started not too late.
In 1966, the United States launched the "Apollo Application Program", which is another large-scale manned space program after the "Mercury", "Gemini" and "Apollo". The purpose is to launch a large-scale manned space station.
In the same year, the United States proposed the "Saturn" S-5B rocket body test module (SSESM, Saturn S-IVB spent-stage experiment support module) program, using the "Saturn" 5 carrier rocket's third-stage rocket body to transform into the main body of the space station. SSESM was defeated in the competition by the Manned Orbital Laboratory (MOL) program.
MOL was cancelled in 1969.
Due to the cancellation of the "Apollo" 18-20 missions, NASA used the remaining three "Saturn" 5 rockets for the space station program, and SSESM was renamed "Sky Lab".
The orbital module is transformed from the third-stage liquid hydrogen liquid oxygen tank of the "Saturn" 5 rocket. The rocket engine and auxiliary structures on it are removed, and the partition is divided into upper and lower parts.
On May 14, 1973, the United States used the "Saturn" INT-21 rocket at the Kennedy Space Center to send the "Sky Lab" into a low-Earth circular orbit with an altitude of 435 kilometers, and then launched three "Apollo" manned vehicles. The spacecraft are called "Sky Lab" missions 2, 3, and 4 respectively.
The "Sky Lab" is the heaviest and most complex man-made celestial body launched by humans into space at a time, weighing about 77 tons.
However, the "Sky Lab" mission did not go well.
More than 60 seconds after the rocket lifted off, the micro-meteor shield was opened in advance and was torn off by the airflow, and a solar panel was also damaged by the airflow. The first group of astronauts had to repair these problems (but the problem was not completely solved, this It is also an important reason for the early closure of "Sky Lab").
The three groups of astronauts stayed in the "Sky Lab" for a total of 171 days, conducted more than 270 studies and experiments, and achieved many results.
The "Sky Lab" was originally planned to operate for 10 years, but it was closed after the third group of astronauts returned to Earth in February 1974. Because of the rising temperature in the cabin and the increased sunspot activity, the "Sky Lab" was not suitable. The astronauts stayed and were forced to close.
On July 12, 1979, the "Sky Lab", which had been in operation for more than 2,200 days, crashed into the atmosphere and burned.
Compared with the continuity of the development of the Soviet space station, the development of the US space station lacks continuity. After the "Sky Lab" was closed, the center of gravity of the United States' aerospace turned to the space shuttle. After the success of the space shuttle, the "Freedom" was launched in the 1980s. Space station plan.
This is an international cooperation project in which Japan, Canada, and ESA have participated. It is the predecessor of the International Space Station.
After the end of the Cold War, the "Freedom" space station also came to a standstill. In 1993, then US President Clinton officially ended the "Freedom" space station program.
After that, the United States and Russia began to contact and discuss cooperation to establish a space station, the "Freedom" space station was reborn, and the International Space Station was born.
In November 1998, the first component of the International Space Station, the Shuguang functional cargo compartment, entered the scheduled orbit. In 2011, the multi-purpose pressurized capsule of the US "Discovery" was sent to the International Space Station. The construction of the space station was completed. Airplane for transportation.
It is worth mentioning that China also wanted to join the International Space Station project at the time, but it was unable to proceed due to the opposition of the United States.
Low-Earth orbit space station will be commercialized
As an international cooperation project, although the International Space Station costs a lot (over 150 billion U.S. dollars and annual maintenance costs as high as four to five billion U.S. dollars), it still has achieved rich scientific research results, including the development of space technology, physics and biology. Gravity research, human physiology, earth science and education, etc.
Looking at the International Space Station project from the current perspective, there are also some shortcomings in the construction and operation of the International Space Station, which are worth studying by later countries. For example, the cost per kilogram of payload is too high (tens of thousands of dollars), the construction period is too long, and the maintenance task is too high. It is more onerous due to the aging of the components.
According to the plan, the initial service period of the space station was 2015, and then it was extended twice, to 2020 and 2024. It was previously planned to be used until 2028. However, the frequent occurrence of air leaks and other problems in the past few years shows that the space station has been decommissioned. Not far away.
In April of this year, Russian Deputy Prime Minister Borisov stated that in view of the severe aging of the International Space Station, the space station operation contract will also expire in 2024. Russia plans to withdraw from the project in 2025 and start building its own space station.
Russia has announced that it intends to build its own space station from scratch. Analysis believes that the experimental module of the "Science" to be launched in July this year will be the core module of Russia's future space station, and construction will be based on this.
The United States is also using its own small calculations. NASA has decided to commercialize the International Space Station. The main goal in the next few years is to guide the client group on funds and contracts.
The United States may cancel relevant funding for the International Space Station before 2025, and the money saved can be used for manned moon landings or fire landings.
The development of the US space station in the future will move towards deep space and commercialization. The "Gateway" lunar space station currently under development is relatively small in size and weight. It is mainly used as a transit station for manned moon landings, while space stations operating in low-Earth orbit may be handed over. To commercial aerospace companies.
In addition, NASA has previously handed over supplies and manned flights to the International Space Station to commercial aerospace companies, with experience and technology meeting the requirements.
According to US media reports in March, NASA recently announced the so-called "Commercial Low-Earth Orbit Destination" (CLD) project. It plans to grant a total of US$400 million to four companies in the fourth quarter of 2021 to help start private companies. The development of the space station to replace the International Space Station.
NASA will become the user of the space station, but not the owner and operator, which can save a lot of money.
In addition to the CLD project, NASA also awarded a $140 million contract to the aerospace company Axiom Space to build a cabin for the International Space Station.
When the International Space Station is decommissioned, Axiom plans to separate its modules and transform it into a space station capable of independent flight.
Seeing the construction of China's space station enter the fast lane, the United States also has the idea of taking a ride.
In June last year, the China Manned Space Engineering Office and the United Nations Office for Outer Space Affairs jointly announced that 9 projects from 17 countries and 23 entities were successfully selected as the first batch of scientific experiment projects of the China Space Station. This is China’s manned space project. The first large-scale international cooperation through the United Nations.
When asked about "Did you exclude projects from the United States when selecting projects," Zhou Jianping, the chief designer of China's manned space engineering, said bluntly: "We did not exclude any country, nor did we limit any scope. There are US teams participating in the declared projects. From In terms of scientific value and technical considerations, American projects did not meet the required standards."