Nan Rendong is widely known as the chief scientist of the Five-hundred-meter Aperture Spherical Radio Telescope (FAST). It has been eight years since his passing, yet his legacy still shines on like a star.

Student days at Tsinghua

Nan entered Tsinghua University in 1963 as the top science student in Northeast China’s Jilin province. Although he initially dreamed of studying architecture, he enrolled in the Department of Radio and Electronics, where he went on to specialize in vacuum electronic devices and ultra-high frequency technology. Classmates remember him as a respected class monitor—steady, reliable, and outstanding in his studies. He could always solve the most difficult exercises in mathematical equations first, and he excelled at mechanical drawing—winning first prize in a university competition in 1965.

Student ID of Nan Rendong during his time at Tsinghua University

Beyond academics, Nan’s dear friends see him as a man of many talents. He drew sketches of campus buildings, compiled nearly a hundred poems into a collection, and even built a small darkroom in his dormitory to develop his own photographs. He was also a keen athlete. Every afternoon at 4:30, he would set out from his dorm, run to the archway at the Summer Palace, and then turn back. At night, he would lie on the University’s sports field with his close friend in the class, pointing out stars and constellations with ease.

Early career and determination

After graduating in 1968, Nan was assigned to work at a radio factory in Tonghua city, Jilin province. There, he helped lead the development of China’s first domestically produced semiconductor radio and television transmitter. Colleagues recall his relentless dedication: he once stayed up all night to examine more than 1,000 circuit points to find a tiny fault in a board, saying, “If the problem isn’t solved, I can’t sleep.” This persistence would define his career.

The FAST vision

In 1994, Nan proposed an ambitious idea: to build a massive radio telescope that could rival the world’s best facilities. Over the next two decades, he led site surveys, and ultimately chose "Dawodang" in Pingtang county as the location. He led the team to drive a series of unprecedented technological breakthroughs.

Nan Rendong (right) surveys "Dawodang" during the site selection.

In 2016, after 22 years of preparation and construction, FAST—also known as “China Sky Eye”—was completed. The Tsinghua spirit of “Actions Speak Louder Than Words” was vividly embodied in Nan Rendong.

A lasting legacy

Nan Rendong (second from left) at a reunion with Tsinghua classmates in early 2015

In early 2015, Nan Rendong invited several of his classmates to gather and share updates on the FAST project. His classmates recalled that his eyes were still as bright as ever.

Nan’s health deteriorated in the final months of the FAST project, but even from his hospital bed he continued to push forward, urging colleagues to resolve technical issues and connect with experts.

Just weeks after his death in September 2017, FAST made its first major discovery, detecting a pulsar signal from deep space—a profound tribute to Nan Rendong’s lifelong dedication.

The FAST venturing into the vast universe

Today, FAST has discovered over 1,000 pulsars and is at the forefront of global radio astronomy. In 2018, the International Astronomical Union named Asteroid 79694 “Nanrendong” in his honor. In autumn 2019, he was awarded the national honor of the People's Scientist title. In 2025, his story entered China’s middle school textbooks under the title There Is a Star Named Nan Rendong.

When Nan’s wife, Guo Jiazhen, donated his belongings from his student days to the Tsinghua University Archives, she said, “Tsinghua was Nan’s lifelong pride. He was always proud to have been a Tsinghua student.”

From the high-flying student in Tsinghua’s classroom to the visionary behind China’s greatest astronomical instrument, Nan Rendong’s life embodied curiosity, perseverance, and a deep commitment to science. His legacy continues to inspire new generations of Chinese students to look up at the night sky and pursue discoveries for the benefit of humanity.

Editors: Li Han, JP