Another option is to build our own habitat in space. They can be located anywhere in the solar system, can be any size allowed by materials science, and can have different characteristics, such as temperature, climate, gravity, and even the length of a day. Of course, we still have a long way to go to build a complete space habitat. However, a paper by the research team of Texas A&M University brings us one step closer to this goal. This paper describes in detail the construction method of an expandable spatial habitat, which consists of concentric cylinders and can accommodate up to 8000 people.
Any space habitat with a large population will have to face some major problems of living in space. The author clearly lists five problems that their space habitat tries to solve: gravity, radiation protection, sustainable agriculture, habitat carrying capacity and commercial value.
gravity
Long-term exposure to the environment lacking gravity will cause serious damage to the human body, leading to various problems such as impaired vision and decreased bone density. But most of these problems can be solved by a simple solution: artificial gravity.
At present, we don't have the technology to make Captain Bikai (see Star Trek) stand on the bridge of the Enterprise, just like standing in an office building. However, we do have something similar to artificial gravity: centrifugal force produced by rotation. This is a quite common solution to provide astronauts with a gravity environment. Although this scheme has not been tested, most experts believe that it can alleviate most health problems related to weightlessness.
There are two main factors to consider when designing an artificial gravity system that can eliminate these health problems. The first thing to consider is the habitat size needed to establish artificial gravity. If the radius of rotation is too small, the gravity felt by human head and feet will be obviously different. This is the cause of the well-known "motion sickness" reaction. Any habitat that causes residents to have such adverse reactions cannot be used.
The second key factor to consider is speed. The author quoted another document, which pointed out that no matter what the speed, as long as it exceeds 4 weeks per minute, it will also induce "motion sickness". Considering the upper limit of rotation speed and the lower limit of rotation radius, we can design the radius of space habitat as 56 meters, which is about the height of the leaning tower of Pisa. Humans can live in such an environment, and will not have "carsickness" and negative effects on health due to continuous zero-gravity floating.
Identical twin astronauts scott kelly and mark kelly are the subjects of NASA's twin research. Scott (right) spent a year in space, while Mark (left) stayed on earth as a control target. Scott was in zero gravity for a long time, which made him relatively weak. Credit: NASA
radiation protection
Zero gravity environment is not the only hidden danger facing space habitats. Long-term exposure to cosmic ray radiation is extremely harmful to human health, and the risk of cancer and cell damage will greatly increase.
The author's solution to this problem is simple-surround the whole habitat with 5 meters thick soil and water. In their model, the radiation shielding layer consists of water and soil layer, and the water layer is sandwiched between the surface soil. The radiation shielding layer, that is, the protective cover, is located outside the cylindrical habitat, which is covered with solar panels to supply power to the habitat. The main reason for choosing water and soil as shielding layer is that these materials are easy to obtain-a lot of water and soil can be obtained from celestial bodies with relatively weak gravity (such as asteroids and the moon). We already know that this combination can effectively stop cosmic rays and solar radiation.
sustainable agriculture
In addition to preventing any potential radiation risk, the shield can also help maintain the life system and eliminate the temperature inhomogeneity of the entire habitat structure through very slow rotation. Through calculation, the author concludes that the internal temperature of the cabin can reach about 300K(27) when the speed of the protective cover is 0.2 rpm and a large-area "radiator" is installed on the side of the cabin. This temperature will be very suitable for the habitat of non-human residents-such as the survival of plants. Habitat farms will be placed at both ends of the cylinder, conical, with transparent glass ceilings at the top. They will also use a slightly tilted giant mirror to reflect sunlight evenly to the surface of crops.
Schematic diagram of the overall structure of "Space Village No.1" habitat. Pay attention to the tension integral string and radiator in the middle of the main structure. Acknowledgements: Chen Muhao, etc.
Habitat carrying capacity
According to the calculation, each crew member of the space station needs about 300 square meters of farmland to support their daily consumption. As the habitat expands to a radius of 224 meters (52 floors, 4 meters high, and the innermost cylinder radius is 20 meters), there will be enough crops and living space to accommodate 8,000 people. However, this habitat can't support everyone at first. The author takes the cylinder with a diameter of 20 meters in the center of the habitat as the "seed" module, and other cylindrical layers will be developed based on this module. This tensioning construction process will adopt mature mechanical engineering technology-tensioning whole.
A robot made by NASA using the principle of tension integrity. Acknowledgement: NASA/Adrian Goguineau & Vitas Sands pilar.
Tensegrity is a compound word created by Buckminster Fuller, which is used to describe a system interwoven with steel bars and strings. In this system, steel bars are compressed and strings are tightened, which enables designers to build some really incredible buildings.
Market value
In terms of spatial habitat, tensegrity technology allows designers to make a six-step expansion plan. With the expansion of habitat, the plan can be repeated indefinitely without shutting down the life support system. Each expansion allows the building complex to add an extra cylinder, which can add a lot of extra living space without destroying the lives of residents in the existing cylinder. This scalability will make any structure that uses this system more economical than the habitat that must maintain a single shape. This economic factor is an extremely important part of any future space habitat design, because it will be the main driving force for the wider expansion of space infrastructure.
Another way to gain economic value by using the interesting characteristics of cylindrical habitats is that the center of the cylinder can act as a "zero gravity workshop", allowing residents to complete tasks that are difficult or impossible to complete in gravity wells, such as processing raw materials or developing new drugs.
3D printed model of space station. Acknowledgements: Chen Muhao, etc.
The central cylinder can also play an important role in another economic driving force-tourism. The designer designed a central open space, which was almost entirely used in the park. This part serves the emotional and psychological health of long-term residents, but it may also become a major tourist attraction. This will be particularly useful because tourism may become one of the main economic drivers of early space habitats.
Space tourism still has a long way to go. Although the launch cost is declining, it is unlikely to build any large space habitat until we have the infrastructure to develop asteroids or the moon. At the same time, we can continue to study new ideas and may finally put them into practice.
A moving train
Thank you for today's authorized translation of the universe. See the original text:
/147882/ design a space habitat with artificial gravity, which can become bigger with time to adapt to more people/
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