Chang'e-4, Yutu-2, and Queqiao — The Mission Brief
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Chang'e-4, Yutu-2, and Queqiao — The Mission Brief

By IndraStra Global News Team

Image Attribute: An image taken from the Lander's Terrain Camera (TCAM) in which Yutu-2 rover is seen rolling out onto the surface of the Moon / Source: CSNA/CGTN

Image Attribute: An image taken from the Lander's Terrain Camera (TCAM) in which Yutu-2 rover is seen rolling out onto the surface of the Moon / Source: CSNA/CGTN.

On January 3, 2019, Chang'e 4, a Chinese lunar exploration mission designed by China National Space Administration (CNSA), achieved the first soft-landing on the far side of the Moon at 02:26 UTC. It became the first spacecraft to do so at the crater called Von Kármán (110 mi/180 km diameter) in the unexplored South Pole-Aitken basin, the biggest known impact structure in the solar system. 

The spacecraft was launched on December 7, 2018 from Xichang Satellite Launch Center at 18:23 UTC on a Long March 3B rocket. It entered lunar orbit on December 12, 2018 at 08:45 UTC. The orbit's perilune was lowered to 9.3 mi (15 km) on  December 30, 2018 at 00:55 UTC. The soft-landing took place on January 3, 2019 at 02:26 UTC. The mission is carrying a rover named Yutu-2, or Jade Rabbit 2 – which left the spacecraft  by driving off a ramp on January 3 at 14:22 UTC.

Chang'e-4, The Lander

Image Attribute: An artist's rendition of Chang'e-4 Lander / Source: CSNA/CGTN

Image Attribute: An artist's rendition of Chang'e-4 Lander / Source: CSNA/CGTN

The lander is carrying multiple payloads, such as a Landing Camera (LCAM), a Terrain Camera (TCAM), a Low Frequency Spectrometer (LFS) to study the solar bursts, a Lunar Lander Neutrons and Dosimetry (LND), which is a neutron dosimeter developed by Kiel University in Germany. It will gather radiation data to be analyzed for future human exploration of the Moon, and will also contribute to solar wind studies.

Also, the lander carries a 6.6 lb (3 kg) sealed "biosphere" with seeds and insect eggs to test whether plants and insects could hatch and grow together in synergy. The experiment includes seeds of potatoes, tomatoes, and Arabidopsis thaliana (a flowering plant), as well as silkworm eggs. Environmental systems will keep the container hospitable and Earth-like, except for the low lunar gravity. If the eggs hatch, the larvae would produce carbon dioxide, while the germinated plants would release oxygen through photosynthesis. It is hoped that together, the plants and silkworms can establish a simple synergy within the container. A miniature camera within the contained will take photographs and report the growth if any. The biological experiment was designed by 28 Chinese universities

Yutu-2, The Rover

Image Attribute: An image of the surface of the Moon taken from Yutu-2 rover's Panoramic Camera (PCAM)  / Source: CSNA/CGTN

Image Attribute: An image of the surface of the Moon taken from Yutu-2 rover's Panoramic Camera (PCAM)  / Source: CSNA/CGTN.

Yutu-2, the rover is carrying a set of scientific instruments, which includes; a Panoramic Camera (PCAM), a Lunar Penetrating Radar (LPR), which is a type of ground penetrating radar, a Visible and Near-Infrared Imaging Spectrometer (VNIS) which is going to be used for imaging spectroscopy that can then be used for identification of surface materials and atmospheric trace gases, and an Advanced Small Analyzer for Neutrals (ASAN), which is an energetic neutral atom analyzer supplied by the Swedish Institute of Space Physics (IRF). It will reveal how solar wind interacts with the lunar surface and perhaps even the process behind the formation of lunar water.

Queqiao, The Magpie Bridge

GIF Attribute: An animation showing Chang'e-4 in lunar orbit and communicating with the Queqiao relay satellite at the second Earth-Moon L2 Lagrangian point. / Source: CAST

Six months prior to Chang'e-4 Mission, CNSA launched the Queqiao, a relay satellite to a halo orbit around the Earth-Moon L2 Lagrangian point on May 20, 2018 from the LC-3 launch pad at the Xichang Satellite Launch Centre (at 21:25 UTC). The satellite was carried by Long March 4C rocket. It has a mass of 937 lb (425 kg), and it uses a 4.2 m (14 ft) antenna to receive X band signals from the lander and rover, and relay them to back to Earth-based control station on the S-band. The name Queqiao means “magpie bridge,” based on the legend of a flock of magpies forming a bridge to reunite the couple.

Image Attribute: A rare schematic diagram of  Queqiao Lunar satellite / Source: Chinese Media

Image Attribute: A rare schematic diagram of  Queqiao Lunar satellite / Source: Chinese Media