The 500 meter aperture spherical radio telescope (fast), known as "China's heavenly eye", was photographed during maintenance on March 29, 2021. Photo / Xinhua News Agency On March 18, the internationally famous science magazine published the new progress of rapid radio burst research. This is the latest scientific research achievement jointly made by "China Tianyan" fast and scientists of Zhijiang laboratory. After the news was reported by the media, it aroused widespread concern of public opinion. However, what new discoveries have China's heavenly eye made and what is the significance of this discovery? News reports are vague, but many astronomy lovers are very concerned. What is "fast radio burst"? The literal meaning of fast radio burst is very easy to understand. Fast means that the duration is very short. A fast radio storm often lasts only one thousandth of a second to one millionth of a second. "Radio" is a special term for astronomy. Other disciplines are generally called radio waves. Although the earth's atmosphere is blocked by clouds and gas molecules, it is transparent to radio waves, so radio telescopes can receive radio waves from the depths of the universe. "Storm" is also a commonly used term in astronomy. In addition to radio storms, there are gamma storms. The difference is that the energy of the explosion is concentrated in different bands of the electromagnetic spectrum. The energy released by a fast radio burst is equivalent to the total energy released by the sun in one day. Fast radio burst is an astronomical phenomenon that releases huge energy in a very short time. Because there is only a concentrated explosion of energy in the radio band, but there is no abnormal phenomenon in the optical band that is easier for humans to perceive, it is impossible to observe with the help of optical telescopes. How the extreme phenomenon of fast radio burst came into being is a frontier topic concerned by the astronomical community in recent years. Astronomers in various countries have put forward more than a dozen different theoretical hypotheses to explain its causes. However, which theory is closer to the real physical process, on the one hand, we should collect enough cases for statistical analysis, on the other hand, it also depends on the improvement of observation accuracy. In other words, we should be both knowledgeable and clear-sighted in order to understand the causes of this mysterious phenomenon. Canada's chime telescope began observation in 2017. The originally planned research goal was cosmology, but during the sky survey, hundreds of fast radio bursts were found, and a batch of repeated bursts of fast radio bursts (repeated bursts) were found, which is called the harvester of fast radio bursts. Some astronomers once thought that fast radio bursts were a one-time attack, which has proved to be wrong. The discovery of repeated violence provides a stage for China's heavenly eye to display its "talent". Because the biggest advantage of China's heavenly eye lies in its high sensitivity, with eyes like eagles and strong eyesight. Why expose the "hiding place"? The universe is a natural giant laboratory. The experimental conditions that human beings can create are completely incomparable with the extreme conditions in the universe. In the sense of astronomical observation, scientists hope to find something in the universe. This time, astronomers used the Chinese sky eye to observe these repeated storms, combined with the observation results of other telescopes such as the U.S. Green Bank telescope and the Australian square kilometer array pilot array (askap), and proposed a physical mechanism that can accurately lock the "Scene" of repeated storms. Astronomers have found that repeated bursts form in the remnants of supernova explosions. In 1054, astronomers in the Song Dynasty observed a sudden brightening in a certain direction in the night sky and recorded it, becoming the first recorded supernova explosion sighting event in history. The Crab Nebula we are now observing is the remnant of that supernova explosion. So, what "criminal investigation means" do astronomers rely on to find the relationship between repeated bursts and supernova explosion remnants? It turns out that after supernova explosion, a large area of nebular material composed of dense free electron gas will be formed, showing a fibrous and unevenly distributed structure, in which neutron stars will be formed. If a neutron star is disturbed for some reason, it will emit a burst of strong radiation, which is a fast radio burst. This intense radiation needs complex scattering in the nebula before it can penetrate into interstellar space and fly to the earth at the speed of light. As radio waves pass through the nebula, some signal characteristics will change. It is these changes that expose the hiding place of repeated bursts. The universe is so big that there are no surprises. If one problem is solved, more problems will arise. Next, astronomers have to face the question of whether repeated bursts are really generated as mentioned above, or whether there are other physical mechanisms, which need to be verified by collecting more cases. In addition, due to the extremely short duration and great energy generated by the fast radio storm, it is similar to the big bang process at the beginning of the universe. Therefore, the study of fast radio bursts may help us better understand the origin of the universe. It is expected that after the warm spring flowers bloom, China's heavenly eye will obtain more new discoveries and become a force to inspire mankind to move forward with science. (Xinhua News Agency)