China launches new satellite to study Sun and space weather

The new satellite, which China successfully put into orbit, was nicknamed Kuafu-1, after a giant from ancient Chinese mythology. The giant pursued the sun and hoped to capture it, while the satellite will study our star – its magnetic field, flares, plasma bursts, as well as space weather.

The official name of the 888-kg satellite is ASO-S (Advanced Space-based Solar Observatory). It was launched on a Long March 2D rocket at 7:43 a.m. Beijing time on October 9 from the Jiuquan Space Center in Inner Mongolia. According to China's state media, the satellite was successfully launched into its target orbit – a sun-synchronous trajectory at an altitude of about 720 kilometers above the Earth.

Using three instruments, the apparatus will study the Sun's magnetic field, solar flares and coronal mass ejections – bursts of plasma flying away from the Sun with enormous speed – for at least four years.

Both solar flares and coronal mass ejections (CMEs) can affect the Earth: powerful CMEs, for example, can cause geomagnetic storms that can disrupt power grids, radio communications and GPS navigation.

ASO-S is expected to generate about 500 gigabytes of data daily: during normal times it will take pictures every few seconds or minute, and during solar flares – at least a frame per second. Ground stations in Sanya, Kashgar and Beijing will receive data from the satellite and redirect it to the analysis center at Zijinshan Observatory.

The satellite will be operational 96 percent of the time of the year: thanks to its location on a sun-synchronous orbit, it will be able to observe the Sun not only during the day but also at night, unlike Earth-based telescopes. At 18 minutes a day the satellite will be able to rest from May to August – in  those moments when the shadow of the Earth will prevent it from seeing the Sun.

Scientists expect the data to tell a great deal about how energy is transported through different layers of the solar atmosphere, and how the solar magnetic field affects the evolution of flares and CMEs. All of this could in the future help facilitate space weather forecasting, which is necessary to better protect valuable aircraft in space.