In 1955, an asteroid was discovered by astronomers ZHANG Yuzhe and ZHANG Jiaxiang of the Purple Mountain Observatory on a photographic plate taken with a 60-centimeter astronomical telescope.

Over the following days, they conducted continuous observations and eventually worked out its orbit, which was immediately reported to the International Astronomical Union’s Minor Planet Center.

The asteroid was later named Zijin-1. This marked the first discovery of its kind by China.

During the following years of less than a decade the Purple Mountain Observatory had discovered a total of 31 numbered asteroids.