Zhu Nenghong

AWARDEE OF ASTRONOMY  PRIZE

ZHU NENGHONG

Abstract

Zhu Nenghong, astronomical optical telescope designer, was born on november 10, 1939 in Shanghai. He was asked to move up one year to graduate from Tong -Ji University and work for Chinese Academy of Sciences. Since then He has engaged in the design of astronomical telescope for Shanghai Observatory.
He was the technician, engineer, vice chief engineer and the deputy director (1983~1991) in Shanghai Observatory. During the period of 1991~1993 he went to the European Southern Observatory located in Garching, near Munich, Germany to take part in the work of the world largest telescope the 16m Very Large Telescope project.
He is now the head of the astronomical instrument research center of Shanghai Observatory and the vice chairman of Shanghai Association for Science & Technology.
 From the end of the 1960s to the early of 1970s he designed a telescope so called “Vacuum Photo Zenith Tube”. It is used to determine the time that the star passing through the meridian circle. Using it the time recording accuracy can be increased from 0.01 sec (the accuracy of the same telescope at abroad) to 0.001 sec. Owing to this project he has got the first class award of National Congress on Science & Technology in 1978.
 Since 1974 he began to design a telescope with the aperture of 1.56 m in diameter. It was the largest telescope before 1996 at home. His major contributions on this project are:
1. Cooperated with Shanghai Xin-hu glass factory to produce the first large mirror blank for astronomical reflector at home, which has the diameter 1.6m and very low thermal expansion coefficient of 2×10-7. The primary mirror and secondary mirror of the telescope are made of this glass. Thus the shape of the mirror can be maintained when the temperature changed.
2. He created a CCD auto-focusing method for compensating the focal plane drift due to the different thermal expansion coefficient between the optical glass elements and mechanical parts.
3. He designed a special mounting that calls fork-yoke mounting of the telescope. It is a combination of fork mounting and yoke mounting. The fork-yoke mounting not only can make the telescope tube point to polar area but also can maintain the point direction between the optical axis of the tube and the star unchanged during observation.
The telescope was completed in 1989 and has excellent image quality. Because of the success of the 1.56 m telescope Zhu Nenghong won a first class Prize of Progress in Science and Technology by Chinese Academy of Science in 1990 and a first class of National Prize of Progress in Science and Technology in 1991.            From 1991 to 1993 he participated the work of Very Large Telescope Interferometer groupe in European Southern Observatory. He did a concept design of the combining telescope 2 m in diameter there.
Zhu Nenghong has designed about ten sets of astronomical telescopes during his 40 working years. He was elected the academician of Chinese Academy of Engineering in 1995.