When it comes to “space stations,” people of course first think of the “home” in the vast space—a manned spacecraft operating in near-Earth orbit. It can also be used by a number of astronauts to work and live long-term.
Similarly, an integrated research platform or integrated laboratory in the deep sea for the exploration and knowledge of the vast ocean is a “deep sea space station.”
The manned submersible Jiaolong is of course also an excellent deep-sea research platform, with its main functions focusing on deep-sea cruising, exploration and sampling, and better mobility. However, it is small in size, carries extremely limited personnel and has a shorter operational time. The deep-sea space station, on the other hand, is relatively large, able to accommodate more people or equipment, and has a much longer operating time underwater. As Yan Kai, director of the State Key Laboratory of Deep Sea Manned Equipment of the 702nd Institute of CSIC, pointed out, the Jiaolong is a submersible that can carry people down several kilometres and operate for 12 hours, but beyond that time it has to resurface; while the Deep Sea Space Station, as an experimental platform operating in the deep sea, can work underwater for a long time and is not affected by the wind and waves on the surface.
Deep-sea space stations and manned submersibles, such as the Jiaolong, or unmanned submersibles and surface vessels can work in conjunction with each other. On the one hand, the submersible can come out of the deep-sea space station like a small boat and operate in the deep sea, or undertake the task of transporting personnel and cargo between the deep-sea space station and surface ships. On the other hand, the deep-sea space station can conveniently manipulate the submersible, or collaborate with the submersible and surface ships, to build a three-dimensional deep-sea exploration system.
Inclusion in the 13th Five-Year Plan
Deep-sea space stations are an essential piece of marine science and technology that should be considered when aspiring to build a strong oceanic nation. In this regard, China has put the construction of a deep-sea space station on its agenda in the process of advancing into the deep blue. The 13th Five-Year Plan stipulates that China will establish deep-sea space stations—deep-sea mobile and fixed space stations—and conduct common technology research in deep-sea exploration, operation, as well as general and special applications. China will carry out research on the fundamental technologies of deep-sea space stations, both mobile and fixed.
A deep-sea space station presents unique challenges compared to a space station in low Earth orbit. First, there is the issue of seawater pressure. As it has to operate at depths of more than 1,000 metres underwater, the space station as a large vessel requires a shell that is resistant enough to overcome the enormous seawater pressure. Further, when docking the submarine to the space station (similar to the docking of a spacecraft to a space station), the above-mentioned difficulties caused by the high pressure of seawater become significant. Secondly, in the darkness of the deep sea, a long-term, sustainable energy supply is the only way to guarantee the time spent on the seabed. Lastly, the space station and relevant equipment need to undergo thorough anticorrosion work to overcome the hugely corrosive effects of seawater. In addition, a technological breakthrough will be essential to effectively achieve foolproof communications, rescue, and security in deep-sea environments.
Towards the 3,000-ton mobile “Dragon Palace”
An expert in ship mechanics and an academician of the Chinese Academy of Engineering, Wu Yousheng, said the deep-sea space station represents a new generation of deep-sea research platforms based on manned submersibles. In recent years, Chinese researchers have accumulated a large number of deep-sea application technologies (such as the “independently designed, independently integrated” manned submersible Jiaolong), which has provided ample reserves of high-precision technology for the construction of deep-sea space stations and has also accumulated rich experience.
Chinese scientists and technicians have long proposed a “three-step” deep-sea space station construction plan: the first step is to build a small deep-sea space station test submarine; second, develop a small deep-sea mobile workstation; and third, build a future-type deep-sea space station that can stay underwater for 60 days. According to another series of manned submersible development tasks at the 702nd Institute of the CSIC, the group has completed the assembly of China’s first experimental deep-sea mobile workstation, developed after 10 years of scientific and technological research.
“Dragon Palace No. 1,” a 35-tonne deep-sea workstation, is capable of carrying six people and working for 12 to 18 hours on the seabed. Director of 702nd Institute, Weng Zhenping, said that a 300-tonne small deep-sea workstation will be built next, followed by 1500-tonne and 3000-tonne deep-sea mobile workstations in the future. Weng Zhenping sketched out the operational picture of China’s future deep-sea space station. That is, besides being able to work on the seabed for longer periods of time, it should also be equipped with a variety of deep-sea robots, such as the carrier platform. Furthermore, a deep-sea submersible such as Jiaolong can serve as a ferry for replacing personnel, replenishing materials, etc., between the surface support system and the deep-sea mobile workstation. As the deep-sea mobile workstation is also equipped with detectors and robots, they can be sent out as far as 30 to 50km, while sending back detection signals and carrying out tasks as instructed. A system like this can be considered the eyes and ears of the deep sea.
Translated from a publicly available article on the Sciencenet, originally published by People’s Daily, 28th June 2017. https://news.sciencenet.cn/htmlnews/2017/6/380686.shtm
Author and original journalist: Baoshu Zhang
Translator: Dongyang Li
Conceptual drawing of a deep-sea space station – Fabien Cousteau’s Proteus