Hard core science fiction animation"PLANETES ΠΛΑΝΗΤΕΣ"has such a picture at the beginning, which shows the process of the female host going to the space station for the first time. Manyou who like to open brain holes asked such an interesting question.How to estimate the diameter of the space station shown in the figure?
There are at least two ways to solve this problem
One is to use painting knowledge and composition. When the spaceship and the space station are in the same frame, we can know the relative proportion, the proportion between the cockpit and the length of the spaceship, and the relative size between man and the cockpit of the spaceship. Thus, the approximate diameter of the space station can be calculated with human as a reference.
Second, first, you can visually measure the rotational speed (angular velocity) of the space station, and then deduce the diameter of the space station according to the artificial gravity in the space station.
Considering that the proportion of animation painting is habitually unreliable, as a science student, I prefer the second of these two ideas. To understand the second problem-solving idea, start withArtificial gravity.
One of the biggest problems in space travel and space survival isWeightless environment. Under weightlessness or microgravity, our body will have the problems of muscle atrophy and bone degeneration. People who have been bedridden for a long time are more likely to understand the pain caused by this degradation of physical function.To solve this problem, you can either open a small stove for equipment training, or create an artificial gravity environment in space.
Naturally, we hope to achieve better artificial gravity, because the effect of exercise is limited, which is not as natural and comprehensive as gravity environment, and such working environment is more comfortable and convenient.
So, how to realize artificial gravity?At present, there are three theoretical methods.
First, it is theoretically feasible to simulate the earth's gravity by acceleration. Gravity and acceleration are equivalent, but experiencing acceleration will experience deceleration. It is not easy to toss back and forth, and it is not easy to create such a large acceleration.
Second, astronauts wear sensing devices by applying external forces through electromagnetic fields, so that the magnetic force applied to the wearable devices can experience gravity. This scheme is not only clumsy, but also similar to the effect of their own exercise. This scheme will encounter the problem that gravity cannot be applied to the interior of the human body.
Third, the centrifugal force is equivalent to gravity by rotation.This is the most reliable and achievable scheme at present.Therefore, we can see that all kinds of hard core science fiction works have rotating spacecraft or space stations like the following figure. The outermost part of the spin is where astronauts experience gravity.
In order to have an intuitive experience of the third scheme, we quote some calculated data to illustrate it.
With a radius of 25 meters, it generates 1g equivalent gravity and rotates once every 10 seconds.
With a radius of 150m, it generates 1g equivalent gravity and rotates once every 24 seconds.
With a radius of 980m (1km), it generates 1g equivalent gravity and needs to rotate once in about 1 minute.
The radius of Nanchang star Ferris wheel turntable, which can rank top in China, is only more than 70 meters, and it takes about 30 minutes to rotate a week. With this reference, the ferris wheel turns from once in 30 minutes to once in more than 20 seconds. The speed should be increased by at least 90 times. It feels like this when it rotates on the artificial gravity space station. A smaller radius can almost confuse people.
It is not difficult for us to find a very contradictory problem.If you want a low speed space station, you have to do it very large, and the cost is huge. You can't afford a one thousand meter radius. At present, there is also an idea to save money by using soft connection to hang a small cabin (that is, a rope is tied to a can cabin at the far end and turn it up), and the technical difficulty is also very high.
Artificial gravity is easier said than done. It is said that the current research direction selected by NASA is the high-speed direction. The plan is to let astronauts sit occasionally and restore the feeling of gravity.Not comfortable, but cheap.
After the introduction of artificial gravity, go back to the previous problem-solving idea 2. The theory and algorithm are clear. It seems that an important parameter is missing.What is the gravity in the space station of PLANETES ΠΛΑΝΗΤΕΣ?Is it a g, or 0.7 or 0.5, etc. How to estimate this. Netizens with big brain holes also gave answers. They should watch the animation carefully. The staff who play with the debris in the space station always accidentally drop things,The gravity of the space station can be calculated according to the falling speed of the object. If you want to be more accurate, you can calculate different objects once and calculate the average value.
What a logical and rigorous answer. The brain circuits of science students are different. Watching an animation can make so many questions.This kind of thinking and thinking spirit is worth praising.Maybe in the future, there will be big stars in the aerospace industry. What do you think of this answer? Welcome to the comment area.
Routine benefits: popular science animation is the same.The ultimate value of life lies in the ability to awaken and think, not just in survival. ——Aristotle.The codeword is not easy. Please pay attention and appreciate it.
