Planned orbital correction canceled for China’s lunar probe

BEIJING—The first orbital correction for China’s first lunar probe, Chang’e-1, scheduled for Thursday, has been cancelled because it is traveling on the expected trajectory, according to the Beijing Aerospace Control Center (BACC).
Chang’e-1 completed its fourth orbital transfer late Wednesday afternoon, shifting out of its 120,000-kilometer orbit around the Earth and moving toward a 380,000-kilometer circumlunar orbit Monday. “We have been controlling Chang’e-1 in a very precise and excellent manner on its expected trajectory, so we decided to call off the first orbital correction planned for 10:25 a.m. Thursday,” said Tong Bin, deputy chief engineer of the BACC.
But Chang’e-1 was still expected to go through one or two orbital corrections before reaching the moon’s orbit at 11:25 a.m. Monday, Pei Zhaoyu, a spokesman for the China National Space Administration (CNSA), said Thursday. “BACC will issue instructions to Chang’e-1 to ignite two small engines on board Friday and slightly modulate its trajectory, in a bid to guarantee that the satellite travels on the pre-set orbit,” Wang said.
A second orbital correction might be carried out Sunday, Wang said. He said that BACC collaborated with the European Space Agency (ESA) Thursday to observe and control Chang’e-1 and all information received from ESA’s tracking station network showed that the moon orbiter was operating normally. “It’s the first time for BACC to conduct such an international cooperation to control Chang’e-1, which will enhance BACC’s preciseness in further controlling the satellite,” he said.
After the probe entered the moon’s orbit, it would brake several times to slow down so that it can be captured by the lunar gravity and become a real circumlunar satellite. It would relay the first picture of the moon in late November and would then continue scientific explorations of the moon for a year.—Xinhua