China's space science program took a major step when its first deep-space probe, Chang'e 1, began orbiting the Moon on November 5th. Two days later the 2½-ton craft — named for the Chinese Moon goddess — dropped to a circular 125-mile-high orbit and prepared to begin its close-up studies of the surface.

State-run China Daily has provided plenty of mission coverage but few specifics about the flight. The scientific payload includes a stereo camera with a resolution of around 400 feet (120 meters) and a laser altimeter that will be used to create a three-dimensional map of the lunar terrain. Chang'e 1 also carries a gamma- and X-ray spectrometer and a microwave radiometer to study the chemical and thermal properties of the surface.

The highest-altitude mission flown previously by China was Tan Ce 1, one of two Double Star satellites launched in 2003 for a collaborative research project with the European Space Agency. The Double Star spacecraft worked with ESA's four Cluster satellites to monitor energetic events in Earth's magnetosphere.

Chang'e 1 is the second Asian spacecraft to reach the Moon in as many months; the first was Japan's Kaguya, which arrived on October 5th. The Asian missions will continue in 2009 with Chandrayaan 1, built by the Indian Space Research Organization. Like its Chinese counterpart, Chandrayaan 1 will first occupy a geostationary transfer orbit before using its onboard engine to reach lunar orbit.