China satellite to explore dark side of Moon
Queqiao to enter a halo orbit around L2 point of Earth-Moon system
THE OTHER face, most of which is never visible from the Earth, is the far side or dark side of the Moon, not because it's dark, but because most of it remains unknown.
Beijing, May 21: China successfully launched a relay satellite on Monday to enable a rover to communicate with the Earth from the Moon's mysterious far side, as part of the Communist giant's ambitious goal of being the first country to send such a probe.
Named Queqiao (Magpie Bridge), the 400-kg satellite has a designed life of three years.
It was carried by a Long March-4C rocket that blasted off at 5:28 AM (local time) from southwest China's Xichang Satellite Launch Center, the China National Space Administration (CNSA) said.
“The launch is a key step for China to realise its goal of being the first country to send a probe to soft-land on and rove the far side of the Moon,” said Zhang Lihua, manager of the relay satellite project.
About 25 minutes after lift-off, the satellite separated from the rocket and entered an Earth-Moon transfer orbit with the perigee at 200 kms and the apogee at about 400,000 kms. The solar panels and the communication antennas were unfolded.
Queqiao is expected to enter a halo orbit around the second Lagrangian (L2) point of the EarthMoon system, about 455,000 kms from the Earth. The satellite carries several antennas. One, shaped like an umbrella with a diameter of five metre, is the largest communication antenna ever used in deep space exploration, said Chen Lan, deputy chief engineer of the Xi'an Branch of the China Academy of Space Technology (CAST).
The satellite could stay in the halo orbit around the L2 point of the EarthMoon system for a long time by using relatively little fuel, thanks to the gravitational equilibrium at that point.
But the mission must overcome many challenges, including multiple adjustments to its orbit and braking near the Moon and taking advantage of the lunar gravity, Zhang said.