Fengyun

Fengyun ( FY) (Chinese风云/风云, wind and clouds) is the name given to a number of Chinese weather satellite, which are brought since 1988 in polar or geosynchronous orbits around the Earth.

The satellites of the FY -1 series are stationed in a polar, sun-synchronous orbit, the satellites of the FY- 2 series in a geostationary orbit. The meteorological satellites provide data for oceanography, agriculture, forestry, hydrology, air and marine, environmental and civil protection and national defense. The latest satellites are able around the clock and in any weather data, eg to deliver over storms, rains, thunderstorms and hail storms. They also monitor the development of sandstorms and can provide measurements of air quality.

The series was known was destroyed on 11 January 2007 as the Fengyun -1C by a Chinese anti-satellite missile test in orbit.

Technology

Fengyun 1

The satellite Fengyun -1A and 1B were cuboid satellites with a size of 1.4 mx 1.4 m floor space. The height was 1.2 m and 1.8 m Fengyun -1B at Fengyun -1A. Fengyun 1C / D had a size of approximately 2 mx 2.00 mx 2.21 m. The power supply of the three -axis stabilized satellite, took two 3.5 m long boom solar cells with a total of 800 W of power and nickel -cadmium batteries. The mass of the satellites increased from 750 kg in Fengyun -1A to 960 kg with Fengyun - 1D. Fengyun -1A and -1B were equipped with a five-channel radiometer. In Fengyun -1C and -1D an advanced Ten channel radiometer was used. This had a resolution of 1.1 km per pixel and a swath width of 2860 km. The transfer of the recordings took place in the same format as for the NOAA satellites and performed at Fengyun 1A / ​​B at a frequency of 137 MHz, while the Fengyun 1C / D sent to 1700.42 MHz ( data rate is 1.3308 Mbps with PSK modulation ).

Fengyun 2

The satellites of the Fengyun -2 series are spin stabilized geostationary satellites of cylindrical appearance with a diameter of 2.1 m and a height of 2.1 m ( 4.5 m with antennas). The payload consists of a radiometer in the visible and infrared range and transmission systems in the S- band and UHF. The radiometer has a resolution of 1.25 km in the visible and 5 km in the infrared range. The take-off mass is between 1250 kg ( FY- 2B) and 1380 kg ( FY- 2C). The first satellite of the series was lost when the carrier rocket of the type CZ -3 on the launch pad caught fire and exploded on April 2, 1994.

Fengyun 3

The newer Fengyun -3 series to replace the weather satellite Fengyun -1 of the series, both of which are stationed on polar sun-synchronous orbits. You are in development since 1998 and used from 2008. The three-axis stabilized satellites are equipped with lists eleven instruments ( including optical radiometer, infrared spectrometer, microwave thermo-and hygrometer and UV detectors for the measurement of the ozone layer and Strahlungsmeßgeräten ). As a take-off mass 2450 kg can be specified. The optical sensors have a swath width of 2,400 km and a resolution of 250 m. They have for the data transfer, two X-band (one for real-time transmission ), and an L band transmitter ( also real-time).

Existing satellite

Planned satellite

The Fengyun -4 series is intended as a substitute for the geostationary satellites of the Fengyun -2 series. With a start is not expected before 2015.