On this day, 28 years ago, May 25, 1997 (April 19, 1997, the international name "Yang Zhenning Star". On May 25, 1997, China Academy of Sciences and the People's Government of Jiangsu Province announced that the International Asteroid Center had officially named the asteroid No. 3421 discovered by the Zijinshan Observatory of the Chinese Academy of Sciences on November 26, 1975, as "Yang Zhenning Star." It is reported that the star orbits the sun in an elliptical orbit, with an average distance of 335 million kilometers to the sun, and it takes 3.34 years to make one revolution. In 1956, American physicists Zhenning Yang and Professor Lee Zhengdao collaborated to propose a new theory of universal non-conservation in weak interactions, and won the 1957 Nobel Prize in Physics.