China's first two satellites dedicated¹ to environment and disaster monitoring were delivered to their users yesterday.

Both Huanjing-1A and Huanjing-1B have two charge coupled device cameras, with a 30-m resolution and a 720-km width, each on board, the State Administration of Science, Technology and Industry for National Defense² said in a statement.

The Ministry³ of Civil Affairs, in charge of disaster relief and reduction, and the Ministry of Environmental Protection are the users of the two satellites.

They can jointly⁴ form the image of China's entire territory in two days, "which not many other satellites with 30-m resolution cameras in the world can achieve", it said.

This enables the two satellites to monitor a designated area repeatedly, fast and inform government agencies of the latest disaster development, it said.

In February, on the Australian government's request to help fight a rare forest fire, the satellites, then under-testing, provided images, Chen Qiufa, the administration chief, said.

Luo Pingfei, vice-minister of civil affairs, said the two satellites would provide a stable, long-term data source to help China fight against disasters.

The two satellites will provide data through the soon-to-open Beijing office of the United Nations Platform for Space-based Information for Disaster Management and Emergency Response for global disaster reduction, Chen said.

The satellites were launched atop the Long March-2C launch vehicle on September 6, 2008, from the Taiyuan Satellite Launch Center in Shanxi province. They passed in-orbit testing in February.

Next year China will launch a small radar⁵ satellite to work with these two optical satellites, the statement said.

Eventually, a total of eight small satellites will be launched to form a constellation⁶ for all-weather, 24-hour monitoring and environment and natural disasters forecast, forming a complete image on China once every 12 hours.

Questions:

1. What are the two satellites called?

2. Who are the two users of the satellites?

3. What launch vehicle was used for the satellites on September 6, 2008?

Answers:

1. Huanjing-1A and Huanjing-1B.

2. The Ministry of Civil Affairs and the Ministry of Environmental Protection.

3. The Long March-2C.