Three years ago, China became the third nation to orbit a spacecraft around the Moon, with the Chang’e-1, in October 2007. India subsequently successfully orbited the Moon with Chandrayaan-1 in October, 2008.
Now, China is on its way back. The Chang’e 2 spacecraft was launched on Friday, the national day of China, at 10:59:57 UTC (3:59 AM Phoenix), beginning the second phase of China’s lunar exploration. The launch was from the Xichang Satellite Launch Center in southwest China’s Sichuan Province.
Chang’e 2 was launched directly into an Earth-Moon transfer orbit.
The perigee is 200 km and the apogee is about 380,000 km. Once in orbit, the perigee will be reduced to 15 km and the apogee to 100 km.
The cameras on the Chang’e 2 should have a resolution of 10 meters at 100 km and 1.5 meters at the 15 km low point, a great improvement compared to the 120 meters of their first lunar orbiter.
The new spacecraft will study the lunar surface using gamma-ray and x-ray spectroscopy, in order to detect the content and distribution of silicon, magnesium, aluminum, calcium, titanium, potassium, thorium and uranium. The thickness of the lunar soil and other properties will be probed by microwave radiation of the lunar surface at 3.0GHz, 7.8GHz, 19.35GHz and 37GHz.