Context:

• China launched a relay satellite on Monday as part of a groundbreaking programme to be the first to land a spacecraft on the far side of the moon later this year.
• The satellite, lofted into space aboard a Long March-4C rocket, will facilitate communication between controllers on Earth and the Chang’e 4 mission.

Other details:

• China hopes to become the first country to soft-land a probe on the moon’s far side, also known as the dark side because it faces away from the earth and is comparatively unknown.
• The satellite, named Queqiao, or “Magpie Bridge,” after an ancient Chinese folk tale, was launched from the Xichang Satellite Launch Centre in the southwestern province of Sichuan.

Multiple challenges

• The launch is a “key step,” but the satellite’s mission must still overcome challenges, including making multiple adjustments to its orbit, “braking” near the moon and using lunar gravity to its advantage.
• Queqiao was expected to arrive shortly at the Earth-moon Lagrange point 2, a gravitationally stable spot located 64,000 km beyond the far side of the moon. Without such a communications relay link, spacecraft on the far side would have to “send their signals through the moon’s rocky bulk.

Other Missions:

• China previously landed its Jade Rabbit rover on the moon and plans to land its Chang’e 5 probe there next year.
• China conducted its first crewed space mission in 2003, making it only the third country after Russia and the U.S. to do so and has put a pair of space stations into orbit.
• Upcoming missions include the launch of the 20-ton core module for the still orbiting Tiangong 2 station, along with components for a 60-ton station that is due to come online in 2022 and a Mars rover planned for mid 2020s.

Source:TH