China is one step closer to landing a probe on the far side of the moon. On Thursday, the relay satellite for China’s Chang’e-4 lunar probe has successfully entered its intended orbit. The satellite will be used to establish a continuous communication between earth and the far side of the moon.
Weighing about 900 pounds, Queqiao or “Magpie Bridge” satellite was launched on May 21 from southwest China. After spending more than 20 days, the satellite entered the Halo orbit around the second Lagrangian (L2) point of the Earth-Moon system, about 65,000 km from the Moon. A Halo orbit is a periodic, three-dimensional orbit near the Lagrange points of two large bodies which is an extremely difficult place to maintain a satellite. Any tiny disturbance, such as gravitational pull from other planets or the Sun could force the satellite to leave this orbit.
“The satellite is the world’s first communication satellite operating in that orbit, and will lay the foundation for the Chang’e-4, which is expected to become the world’s first soft-landing, roving probe on the far side of the Moon.” Zhang Hongtai, president of the China Academy of Space Technology (CAST) said in a statement.
China is pouring billions into its space program and aiming to land its Chang’e-4 probe – named after the moon goddess in Chinese mythology – on Aitken Basin sometimes later this year. South Pole-Aitken Basin is a vast impact region in the southern hemisphere and measure roughly 2,500 km in diameter, making it the single-largest impact basin on the moon and one of the largest in the solar system. Since this far hemisphere always faces away from Earth, it is also known as the dark side of the moon. If successful, China will become the first country to send a mission on the far side of the moon. Overall, Chang’e-4 will be the second Chinese probe to land on the Moon following the Yutu rover mission in 2013.