Scientific rambling
During the two sessions, a short ** quickly became popular all over the Internet, and a reporter from Xinhuanet interviewed Jiang Peng, the chief engineer of China's "Sky Eye", and once again popularized the science of the world's largest aperture and the highest precision single-antenna radio telescope.
I believe that many people know China's "Sky Eye", this well-known "cauldron", with a diameter of 500 meters, is destined not to be an ordinary "pot".
You must know that its aperture is 200 meters larger than the world's second largest radio telescope, the "Arecibo Telescope", which is nearly twice the difference, and this is not the full strength of China's "cauldron".
As mentioned by a reporter from Xinhuanet, only when you observe it in person, can you feel the shock it brings us.
500 meters in diameter, the total area of the reflective surface is 250,000 square meters, which is equivalent to the area of 30 standard football fields.
This is also the reason why China's Sky Eye was able to discover 833 pulsars in a short period of time, and this data is expected to exceed 1,000 this year.
What exactly does this number mean? As Chief Engineer Jiang Peng said:
During the same period, it was three times the total number of pulsars discovered by all other telescopes in the world, and it is currently the most efficient astronomical observation equipment for discovering pulsars in the world.
This is the pride of a big country, is a romance that belongs to the Chinese, today we will talk to you about this "cauldron" that makes the world extremely envious and shocked - China's Tianyan.
The proposal of China's Tianyan plan can be traced back to the 90s of the last century.
In 1993, astronomers proposed a plan to build a giant telescope at the International Radio Union Conference, and after continuous exploration, Chinese astronomers proposed a preliminary plan for the construction of the Sky Eye Project in Guizhou.
You must know that the aperture of China's largest radio telescope at that time was less than 30 meters, and the construction of such a large aperture telescope is very important in terms of technical strength and economic support.
China's annual GDP in 2023 is 12606 trillion, while GDP in 1993 was only 357 trillion, not even a fraction of what it is now.
But Chinese scientists just dare to think and do, and the most important thing is that we succeeded in the end.
Some netizens often ridicule China's science and technology as "foreign fantasy China realization".
There were so many scientists who proposed to build a giant telescope, but in the end, only Chinese scientists took it seriously."
The more high-end science and technology, Europe and the United States are only responsible for fantasy, while China is responsible for realization".
Obviously, although China was poor at that time, it was "not short of ambition", and in 2005, China's Tianyan plan officially passed the review, and the project was launched in the same year.
A radio telescope with an aperture of 500 meters was a big project, both at that time and now, not to mention that China had not accumulated experience in building large-aperture telescopes before, and it was completely "crossing the river by feeling the stones".
Finally, after 6 years of construction, the China Sky Eye project was successfully completed and soon put into use.
On the 22nd of last month, China's Sky Eye has successfully discovered 833 pulsars, and Chief Engineer Jiang Peng said that he will strive to break through 1,000 this year, but he still hopes to find some more meaningful and special pulsars.
Is the reason why China's Tianyan is so good is because it is big enough?
That's right, because it's big enough!
Chief Engineer Jiang Peng said that astronomers have a final question:The origin of the universe, the origin of the stars, the origin of life.
To understand this, we need telescopes with large enough aperture to help us see farther and wider, to discover more truths about the universe.
Of course, if you think that China's Sky Eye is famous all over the world just because it is big enough, then you are underestimating our scientists.
First of all, the most important thing to build a large-aperture telescope is to select the site, which needs to consider the topography, landform, and even meteorological conditions.
In those years, Nan Rendong, the father of Tianyan, carried more than 300 satellite remote sensing maps to the mountains and mountains of Guizhou, and encountered dangers many times, and each time it was full of dangers.
In the end, out of nearly 400 alternative depressions, the current location was chosen.
Of course, in addition to site selection, the surface accuracy requirements for large-aperture telescopes are also very high, especially for radio telescopes, because they need to accurately receive and focus weak radio signals.
The shape and precision of the surface have a direct impact on the performance of the telescope, so highly sophisticated measurement and adjustment techniques are required.
Finally, the radio signal received by large-aperture telescopes is usually weak, so an efficient signal processing system is required.
This includes advanced digital signal processing, data storage, and processing algorithms to extract useful astronomical information from large amounts of data.
In short, we will find that in addition to building a large-aperture radio telescope, there are also large and fine, thick and fine, and every step must be taken into account, and it must be done carefully and meticulously.
So the question arises again, why is the larger the aperture of radio telescopes, the better?
Here we have to mention one name: angular resolution.
Angular resolution is generally the resolution of the imaging system, and to put it intuitively, when you find a star, you need to be able to tell who is who?
From a scientific point of view, angular resolution is the ability of a telescope to resolve the minimum angle between two adjacent celestial bodies.
According to the radio interferometry formula of radio astronomy, angular resolution is inversely proportional to the ratio of wavelength and telescope aperture. Therefore, the larger the aperture, the higher the angular resolution observed, and the telescope can resolve the details of the celestial object more clearly.
As we mentioned earlier, the signal received by radio telescopes is actually very weak, so the telescope needs to have a relatively high sensitivity, and the sensitivity is proportional to the aperture of the telescope.
In addition to the relatively weak signals we receive, some stars that are very far away from us also have very weak signals, so large-aperture telescopes need to have strong light collection capabilities.
To put it bluntly, it is necessary to be able to collect the faint signals emitted by those distant celestial bodies.
Finally, there is the wavelength, knowing that it is not enough for us to find those celestial objects, but also to be able to locate them, and the beam shape of the radio telescope is related to its aperture and wavelength.
Large-aperture telescopes, on the other hand, typically have a narrower main beam, which allows the telescope to locate the location of the radio source more precisely.
Therefore, we will find that China's Tianyan is far more simple than what we see, it is not a simple "cauldron", in which the painstaking efforts and research results of Chinese scientists are hidden.
After talking so much, are you becoming more and more interested in China's Tianyan?
If you have time this year, you can go to the China Tianyan Scenic Area to see its style, in addition, this scenic spot is free!