Mikhail Kotov - about China's plans to launch a telescope module into space with a resolution coefficient equivalent to the Hubble telescope
Image source: © CNSA/Xinhua via AP
According to the expansion plan of the Chinese orbital program, the launch of the newest 20-ton observatory will take place in the next two years. According to Zhou Jianping, chief designer of the Manned Space Program of the People's Republic of China, "the new orbital telescope with a resolution coefficient equivalent to the Hubble telescope will have a lens with a diameter of over 2 m and a field of view 300 times larger than that of the American orbital telescope." At the same time, the telescope module will be in the same orbit as the Chinese Tiangong station.
For understanding, modern manned cosmonautics is now often criticized. The position of specialists who express a negative assessment is quite simple and understandable: orbital multimodule stations, such as the ISS or the Chinese Tiangong, are not far from the first samples - the Soviet Salyut or the American Skylab.
No movement
Of course, from a technical point of view, especially in matters of management and communications, there have been significant changes. The ability to use the Internet in space and provide high-quality broadcasts is a really good step forward. But the functionality of the stations itself has not changed much. What then, what now they are perceived only as an opportunity to ensure the life of astronauts in orbit and the organization of scientific experiments. No new functions that radically change the situation have been added during their existence.
Unless it can be noted that the International Space Station has a special gateway for launching cubesats satellites (small Earth satellites for space exploration, with dimensions of 10x10x10 cm with a mass of no more than 1.33 kg). But that's probably all. Even space tourists who find themselves on the station can only join the scientific program. But once it seemed that the exclusively scientific use of stations was only the first stage of space development. In the 1960s, experts were sure that more specialized modules in orbit were a matter of the next few years, at most decades, and very soon orbital production facilities using the possibility of microgravity would be operating in space, orbital shipyards for spacecraft would open. In the minds of people, the construction of space hotels and medical centers was imagined (it was assumed that in zero gravity a number of diseases would be much more effective to treat), lunar stations for convenient landing on the surface. However, none of this has appeared since then. Even the first feature film in space was shot quite recently, although, it would seem, such a passing use of the station has been asking for a long time.
Accordingly, when orbital stations are criticized for the lack of serious functional development, it is difficult to disagree with this. Development is much slower than it seemed from the twentieth century. There are projects of space hotels, but no national cosmonautics has yet reached their implementation.
Pit stop for the telescope
And here is an excellent option for a new use of their orbital station offered by the Chinese. It is assumed that in the next two years, a space observatory similar to the American Hubble project will be launched from Earth into the same orbit as the Tiangong station. The module will work autonomously most of the time, but with the ability to dock to the orbital station at any time. The connection of the telescope will allow astronauts to replenish its fuel reserves, carry out any routine maintenance and repair work.
Why does this opportunity seem so important to me? The fact is that currently the duration of operation of orbital observatories can reach several decades. The modern scheme for the creation of spacecraft according to an unpressurized scheme, without special containers inside which electronics worked, made it possible to significantly extend the life of spacecraft and simplified the possible work with them in orbit. And the main factor that limits the operating time of such a spacecraft is only the availability of fuel for maneuvers. The possibility of refueling the telescope will allow you not to save fuel and prolong the active operation of the space observatory.
In addition, there are likely situations when the telescope will need maintenance, as it was, for example, with the same Hubble. Its architecture also initially supported the possibility of maintenance in orbit, and the observatory needed this opportunity almost immediately. After its launch in 1990, it turned out that there was a problem in the optical system of the telescope: Hubble was unable to achieve the desired sharpness, and the resolution of the images was significantly worse than expected, although better than that of its colleagues placed on Earth. The investigation showed that the source of the problem was the incorrect shape of the main mirror. Due to an error by the company responsible for polishing the mirror, despite all sorts of checks, it turned out to be too flat at the edges. The deviation from the given surface shape was only 2 microns (for understanding, the diameter of a human hair is 40-120 microns), but as a result, the mirror had a strong spherical aberration, and the quality of the images received suffered significantly from this. At that time, the American Space Shuttle program was working, during which the crew and cargo were transported from Earth to its orbit. As part of it, a special corrective lens was delivered to Hubble, which the astronauts installed on top of the telescope structure.
Currently, Hubble is still working, but there is no opportunity to carry out any work with it in space now - the Space Shuttle program was closed due to high cost and insufficient security in 2011. But the Chinese telescope, as expected, such a problem is eliminated in advance - as long as the Tiangong station is used, it will always be able to approach it for refueling and any routine maintenance. Such use of the orbital station seems to the expert community to be very effective and innovative. We can say that this is the step we have been waiting for for a long time.
