Facility set up to stop destructive solar rays

By Lin Shujuan (China Daily)
Updated: 2008-09-24 07:13

China has started construction of a facility in the Inner Mongolia autonomous region that can detect solar bursts.

Known as the Chinese Spectral Radioheliograph (CSRJ), it will be operated by the National Astronomical Observatories of the Chinese Academy of Sciences.

When completed in 2010, the CSRJ will be able to detect solar flares and forewarn of coronal mass ejections (a plasma consisting primarily of electrons and protons) that can disable satellites and knock out power grids.

The CSRJ is one of two major ground-based solar facilities China is constructing. The other is a 500-m Aperture Spherical Telescope (FAST), the largest radio telescope in the world, under construction in Guizhou province.

Construction of the 500 million yuan ($73 million) CSRJ started earlier this month in the Zhengxiangbai banner of Inner Mongolia, about 260 km northwest of Beijing.

"The sun has a great impact on the Earth's environment, especially the climate when there are solar activities such as coronal mass ejections, flares, and solar energetic particles," Ye Shuhua, one of China's leading solar scientists, said.

"The CSRJ will enable us to study such solar activities - when and where they will take place - so that we can get prepared and react properly," Ye said.

The CSRJ's chief researcher, Yan Yihua, said: "The world has found answers to questions on why and how the sun 'gets angry', but has yet to know when and where it might affect the Earth's environment."

Ideal location

The CSRJ will consist of 100 radio dishes, 40, 4.5 m wide and 60, 2 m wide.

The dishes will be clustered together in a 3 km zone, devoid of earthly radio waves.

"Radio bursts from the sun are very faint, so there must not be any disturbance," Yan said.

After years of searching, Ming'antu in the Zhengxiangbai banner was found to be the ideal location.

Ming'antu is the hometown of astronomer Ming'antu, a Mongolian ethnic during the Qing dynasty.

A complementary facility, the Frequency-Agile Solar Radiotelescope (FASR) is being constructed by the US National Radio Astronomy Observatory in Owens Valley, California.

"CSRJ and FASR, located on opposite sides of the globe, will complement each other. They will be able to monitor the sun for the whole day," Yan said.