Is the “Sky Eye” useless? Chief scientist: Basic research has never been driven by “use”

On the afternoon of July 9, Li Di, chief scientist of the "China Sky Eye", was awarded the Marcel Grossmann Individual Award for his many creative achievements, including leading his team to use the China Sky Eye FAST to achieve precise measurements of interstellar magnetic fields and promote the research of fast radio bursts into the high-statistics era. The Marcel Grossmann Award is one of the most important awards in the international physics community. Past winners include six Nobel Prize winners, including several Chinese scientists such as Chen Ning Yang, Tsung-Dao Lee, and Shing-Tung Yau. Li Di is the first scientist to win this award for his academic achievements in China.

Li Di (right) won the Marcel Grossmann Award

Previously, the research of Li Di's team in the field of fast radio bursts was selected as one of the top ten scientific advances in China for two consecutive years. Some people believe that their research results all come from FAST, so the honor and credit should belong to Nan Rendong, the "Father of the Sky Eye". In response to this sharp view, Li Di responded: "Of course it is. In the field of observational astronomy, without advanced equipment, there will be no achievements. The credit for the Sky Eye is mainly attributed to the older generation of predecessors. I am a builder and beneficiary of this large scientific device. I must use it as best as possible at the right time and in the right place."

"Sky Eye" explores the mysteries of the universe

In the process of human exploration of the universe, building large astronomical telescopes is an indispensable part. In the 1990s, Chinese astronomers often relied on foreign advanced equipment and data to ensure the accuracy and reliability of their research results. In 1994, astronomer Nan Rendong, who was a visiting professor in Japan at the time, proposed to build the world's largest radio telescope on Chinese soil to prevent China from being controlled by others in the exploration of the universe.

In order to select a site, Nan Rendong took more than 300 satellite remote sensing images and visited almost all the depressions in the mountains of Guizhou. He finally set his target on a karst depression called Dawodang in Kedu Town, Pingtang County.

As early as 2002, Li Di met Nan Rendong at a meeting in China after graduating from Cornell University with a doctorate. He took the initiative to ask whether the construction of FAST needed young scientists to join. At that time, Nan Rendong hoped that he would continue to recharge abroad. Until 2008, Li Di was hired by the Chinese Academy of Sciences as a part-time FAST project scientist. In 2012, he returned to China and joined the National Astronomical Observatory to participate in the construction of FAST.

On September 25, 2016, the FAST project, known as the "China Sky Eye", was finally completed and put into use. After 22 years of hard work, this miracle in the field of international astronomy was finally created. As the world's largest single-aperture radio telescope, FAST not only broke all records in terms of scale, but also led the world in technology, providing unprecedented tools for astronomical research.

The five major scientific goals of FAST were clearly defined at the beginning of its construction, including patrolling the universe for neutral hydrogen, observing pulsars, and searching for signals from extraterrestrial civilizations. In 2017, Nan Rendong, chief scientist and chief engineer of the "China Sky Eye", passed away. The following year, Li Qi took over as the chief scientist of FAST. In the first few years, he was under a lot of pressure. "When will FAST make a major discovery? Domestic and foreign users will compare FAST with international telescopes. Can it withstand those harsh evaluations?"

China's Sky Eye FAST

FAST's observation capabilities are amazing. Its receiving area is equivalent to the sum of 30 optical telescopes or 120 infrared telescopes. Not only that, its sensitivity is more than three times that of the world's largest 100-meter radio telescope. This means that China's Sky Eye can observe more distant celestial bodies and detect much smaller signals.

For example, FAST can observe high-energy phenomena such as "fast radio bursts", which are mysterious phenomena from the depths of the universe. Until now, people still do not know the nature, physical mechanism and true origin of fast radio bursts, which has attracted astronomers around the world to study them. China's Sky Eye has unique advantages in observing these phenomena, providing more possibilities for solving this mystery of the universe.

"The energy released by fast radio bursts in a few milliseconds is equivalent to the energy released by the sun in several days or even a year. Studying the generation mechanism of such extreme explosions may have a revolutionary impact on physics and astronomy," said Li Di.

As an emerging field, fast radio bursts are one of the major hot frontiers in astronomy, and there is fierce competition among international peers. To study it well, it is generally necessary to go through three stages: first discover a sufficient number of fast radio bursts, conduct in-depth observations on this basis, and finally find its location. Li Qi's team also remained calm enough. Among these three steps, FAST has an advantage in the second link compared with other telescopes due to its high sensitivity and long observation distance, but in order to develop in the long term, the other two steps need to be completed.

Curiosity is the driving force of scientific research

Contrary to what many people imagine, scientists who use the "Sky Eye" to observe the stars are not really "looking at the stars", but calculating and exploring from massive amounts of data in the office.

FAST has powerful data processing capabilities. Every day, the telescope collects a huge amount of data. In order to process this data, FAST is equipped with a first-class computer cluster and algorithm. By analyzing this data, researchers can study more astronomical phenomena and further promote human understanding of the universe.

"Basic research has its own characteristics. You have to sit on the bench for a long time at the beginning, or you don't get much positive feedback. Your initial curiosity and interest in it are crucial factors in determining how far you can go in the future." Every member of the team does not find their daily work boring, but enjoys it. In their view, there are two prerequisites for doing something well: passion and expertise. The order of the two cannot be reversed.

Today, the "China Sky Eye" has not only become a world-class astronomy research and exchange center, but also one of the world's important astronomy popular science bases. FAST is driving a wave of astronomy popular science research and study, and has played a unique role in improving the astronomical knowledge literacy of the whole people. Since its opening in 2016, the "China Sky Eye" popular science base has won the titles of "National Popular Science Demonstration Base", "National Popular Science Education Base", and "National First Batch of Research and Tourism Education Practice Bases for Primary and Secondary School Students". FAST is playing a greater role in training scientific researchers and promoting popular science education, inspiring more children's curiosity about astronomy.

Li Di, chief scientist of the "China Sky Eye"

Basic research is driven by curiosity, so even if it is useful, it is not driven by "use". The core goal of FAST is the seemingly "useless" basic astronomical research, but the technological progress generated by the construction process of FAST has fed back to China's industrial system. For example, FAST's high fatigue resistance cable technology has been applied in the Hong Kong-Zhuhai-Macao Bridge. Not only that, by participating in the construction and use of astronomical large-scale scientific projects represented by FAST, a group of people have the honor of becoming the beneficiaries and contributors of China's historic process of rapid development in the past few decades.

"The fact that it can exist without being useful shows that curiosity is a necessary condition for the survival of individuals and groups, just like being well fed and well clothed. If humans don't explore many things now, they may not be able to face unimaginable survival crises in the future," said Li Qi. "Astronomy is a science that is both ancient and modern. It is the most basic of the basic sciences. Even if it has no visible use at the moment, it is for the future."