Shiyan (SY, ) is a Chinese experimental satellite program consisting of a variety of test satellites. Given the

classified Classified may refer to: General *Classified information, material that a government body deems to be sensitive *Classified advertising or "classifieds" Music *Classified (rapper) (born 1977), Canadian rapper * The Classified, a 1980s American ro ...

nature of the satellites, Chinese government statements regarding the missions of Shiyan satellites follow the common refrain of agricultural monitoring and space environment observation — the same offered for other classified programs such as the Tongxin Jishu Shiyan,

Yaogan Yaogan () is the designation used by the People's Republic of China to refer to its military reconnaissance satellites. Yaogan satellites are largely known to primarily support the People's Liberation Army's Strategic Support Force (PLASSF), f ...

, and

Shijian Shijian (, Abbreviation, abbr. "SJ") is a series of satellites built and operated by the China, People's Republic of China. Some Shijian-series satellites have drawn significant concerns from the United States government and space observers who ...

programs. Alternatively named Tansuo satellites, Shiyan satellites occupy varying orbits including low Earth, polar

Sun-synchronous A Sun-synchronous orbit (SSO), also called a heliosynchronous orbit, is a nearly polar orbit around a planet, in which the satellite passes over any given point of the planet's surface at the same local mean solar time. More technically, it is ...

geosynchronous A geosynchronous orbit (sometimes abbreviated GSO) is an Earth-centered orbit with an orbital period that matches Earth's rotation on its axis, 23 hours, 56 minutes, and 4 seconds (one sidereal day). The synchronization of rotation and orbital ...

, and highly-elliptical orbits and are believed to accomplish a diverse set of missions from rendezvous proximity operations (RPO) to earth imaging. Though similarly named, the Shiyan satellite program is not to be confused with the separate Shijian satellite program.

Notable satellites

Shiyan 7

Shiyan 7 was launched from

Taiyuan Satellite Launch Center The Taiyuan Satellite Launch Center (TSLC) also known as ''Base 25'' (), is a People's Republic of China space and defense launch facility (spaceport). It is situated in Kelan County, Xinzhou, Shanxi Province and is the second of four laun ...

(TSLC) on 19 July 2013 aboard a Launch March 4C rocket into low Earth,

Sun-synchronous orbit A Sun-synchronous orbit (SSO), also called a heliosynchronous orbit, is a nearly polar orbit around a planet, in which the satellite passes over any given point of the planet's surface at the same local mean solar time. More technically, it is ...

, accompanied by the Shijian 15 (of unknown mission) and Chuangxin 3. Three weeks after launch, from 6–9 August 2013, Shiyan 7 performed rendezvous operations with its companion payload, Chuangxin-3, supporting speculations of a

robotic arm A robotic arm is a type of mechanical arm, usually programmable, with similar functions to a human arm; the arm may be the sum total of the mechanism or may be part of a more complex robot. The links of such a manipulator are connected by join ...

-wielding satellite tasked with rendezvous proximity operations (RPO). Later, Shiyan 7 shifted to rendezvous with Shijian 7 (of unknown mission) with whom it maintained proximity from 19 to 20 August 2013 until it maneuvered into a 5 km lower orbit. Drawing further suspicion, around 19 October 2013, Shiyan 7 maneuvered to a 1 km higher orbit and released a previously untracked object, designated which many believe to be a

subsatellite A subsatellite, also known as a submoon or informally a moonmoon, is a "moon of a moon" or a hypothetical natural satellite that orbits the moon of a planet. It is inference, inferred from the empirical study of natural satellites in the Solar S ...

to RPO experiments. Such operations, which the Chinese government does not comment on, has sparked debate around the nature of Chinese experimental satellites.

Satellites

References

{{Orbital launches in 2023 Reconnaissance satellites Earth observation satellites of China Spacecraft launched by Long March rockets Satellite series Military equipment introduced in the 2000s Satellites of China

Notable satellites

Shiyan 7

Satellites

See also

References