Chinese Astronomy and Astrophysics translates articles predominantly from Acta Astronautica Sinica (AAnS) and Acta Astrophysica Sinica (AApS),and occasionally from other related Chinese-language journals such as Chinese Journalof Space Science (CJSS). All these journals employ a peer referee system. Contributionscome mainly from the following centres of research and increasingly more papers originate ininternational cooperative work.

Purple Mountain Observatory, Academia Sinica, Nanjing.

Beijing Astronomical Observatory, Academia Sinica, Beijing.

ShanghaiAstronomical Observatory, Academia Sinica, Shanghai.

Department of Astronomy andAstrophysics, Nanjing University, Nanjing.

Centre for Astrophysics, University ofScience and Technology of China, Hefei, Anhui Province.

Department of Astronomy andAstrophysics, Beijing Normal University, Beijing.

Astronomical Division, Department ofGeophysics, Peking University, Beijing.

Yunnan Observatory, Academia Sinica.Kunming, Yunnan Province.

Shaanxi Observatory, Academia Sinica, Lintong, ShaanxiProvince.

Factory of Astronomical Instruments, Academia Sinica, Nanjing.

It is ouraim to cover all the significant papers and our translation generally appears within four to sixmonths of the Chinese original.

Notes on Chinese Romanisation, the way Chinese namesare written and the traditional sexagenary cycle are given on the inside back cover.

Pleaseaddress all editorial matters to the translation editor, Professor S. Wang, Beijing AstronomicalObservatory, Chinese Academy of Sciences, Beijing 100080, China.