Queqiao
Queqiao — a Chinese relay satellite launched on 20 May 2018, the first spacecraft to work from a halo orbit around the Earth–Moon L2 point, about 65,000 km beyond the Moon. From there it saw both Earth and the far side, and relayed the signals of Chang'e 4, the first landing on the far side, in January 2019. Built for three years, it handed its work to Queqiao-2 in 2024; whether it still operates has not been announced. (Its loop is drawn from the published height and period; its width and its position on it are representative.)
Key facts
Mission & specifications
Mission
- Operator
- CNSA
- Launched
- May 20, 2018
- Status
- Completed
Trajectory
- Distance from the Sun
- 1 AU
- Computed from the cached position
- Distance from Earth
- 0.263 AU
- Computed from cached positions
- Distance from Venus
- 0.312 AU
- Computed from cached positions
Mission
The Moon always turns the same face to Earth, so a lander on the far side cannot talk to Earth directly. Queqiao, "Magpie Bridge", after the bridge of birds in the Chinese legend of the Cowherd and the Weaver Girl, was built to carry those signals. It was launched on a Long March 4C from Xichang on 20 May 2018 at 21:28 UTC. It passed the Moon on 25 May and on 14 June entered a halo orbit around the Earth–Moon L2 point, a place beyond the far side where the pull of Earth and the Moon lets a spacecraft loop around empty space. The loop takes 14 days and carries it 47,000 to 79,000 km from the Moon and 13,000 km above and below the Moon's orbital plane, so it always sees both Earth and the far side. It was the first spacecraft to work there. Its 4.2 m antenna relayed the landing of Chang'e 4 in Von Kármán crater on 3 January 2019 and years of the Yutu-2 rover's drives. Small engine burns about every nine days kept it on its loop. It also carries a Dutch-Chinese low-frequency radio instrument. Built for three years, it had outlived that by 2024, when China said Queqiao-2 would take over its relay work.
- 2018Queqiao launches toward the Moon on a Long March 4C rocketLaunch
From Xichang.
- 2018In a halo orbit around the Earth–Moon L2 pointArrival
Beyond the far side, where it sees both Earth and the far side.
- 2019Relays the first landing on the far sideMilestone
Chang'e 4, in Von Kármán crater.
Images
Images from open archives · credit shown per image