Two environment and disaster monitoring satellites officially began operating Monday, China's State Administration of Science Technology and Industry for National Defence (SASTIND) said.

The two small optical land observation satellites, Huanjing-1A and Huanjing-1B, would play an important role in providing data as part of the United Nations Platform for Space-based Information for Disaster Management and Emergency Response (UN-SPIDER), a UN program to provide such information universally, an unnamed SASTIND official told Xinhua.

With advanced optical, thermal infrared and hyper-spectral remote sensing equipment, the satellites would greatly raise China's ability to monitor the environment, Wu Xiaoqing, Vice Minister of Environmental Protection, said at a ceremony to mark the event.

During their trial services since late 2008, the satellites provided images for members of Asia-Pacific Space Cooperation and helped with management of the Australian bushfires, which claimed 210 lives in February.

The two optical satellites, the first of their kind put into space by China, were launched from the Taiyuan Satellite Launch Center in Shanxi Province on a Long March 2C rocket on Sept. 6, 2008.

They can provide a global scan every two days in a lifespan expected to last more than three years.

The satellites form part of China's effort to create a constellation of four optical and four radar satellites for environmental and natural disaster monitoring.

Radar satellite Huanjing-1C, the third in the constellation, is expected to be launched this year.

Small, or miniaturized, satellites are characterized by small size and low weight, usually under 1,000 kg. They require smaller, cheaper launch vehicles and can sometimes be launched in multiples.

(Xinhua News Agency March 31, 2009)