Chang'e 4 lander and Yutu-2 rover
|Mission type||lunar rover|
|Mission duration||3 months (planned) |
Current: 743 days
|Launch mass||Rover: 140 kg|
|Landing mass||140 kg|
|Dimensions||1.5 × 1.0 × 1.0 m|
|Start of mission|
|Launch date||7 December 2018, 18:23 UTC|
|Rocket||Long March 3B|
|Launch site||Xichang Satellite Launch Center|
|Landing date||3 January 2019, 02:26 UTC|
|Landing site||Von Kármán crater in the South Pole-Aitken Basin|
|Distance covered||565.9 m (1,857 ft)|
as of 25 October 2020[update]
Yutu-2 is a robotic lunar rover that formed part of the Chinese Chang'e 4 mission to the Moon. It was launched on 7 December 2018, 18:23 UTC. It entered lunar orbit on 12 December 2018, before making the first-ever soft landing on the Moon's far side on 3 January 2019, and is currently operational as the first lunar rover on the far side.
The total landing mass is 1,200 kg (2,600 lb). Both the stationary lander and Yutu-2 rover are equipped with a radioisotope heater unit (RHU) in order to heat their subsystems during the long lunar nights, while electrical power is generated by solar panels.
After landing, the lander extended a ramp to deploy the Yutu-2 rover (literally: "Jade Rabbit") to the lunar surface. The rover measures 1.5 × 1.0 × 1.0 m (4.9 × 3.3 × 3.3 ft) and has a mass of 140 kg (310 lb). Yutu-2 rover was manufactured in Dongguan, Guangdong province; it is solar-powered, RHU-heated, and it is propelled by six wheels. The rover's nominal operating time is three months, but after the experience with Yutu rover in 2013, the rover design was improved and Chinese engineers are hopeful it will operate for "a few years."
- Panoramic Camera (PCAM), is installed on the rover's mast and can rotate 360°. It has a spectral range of 420 nm–700 nm and it acquires 3D images by binocular stereovision.
- Lunar penetrating radar (LPR), is a ground penetrating radar with a probing depth of approximately 30 m with 30 cm vertical resolution, and more than 100 m with 10 m vertical resolution.
- Visible and Near-Infrared Imaging Spectrometer (VNIS), for imaging spectroscopy that can then be used for identification of surface materials and atmospheric trace gases. The spectral range covers visible to near-infrared wavelengths (450 nm - 950 nm).
- Advanced Small Analyzer for Neutrals (ASAN), is an energetic neutral atom analyzer provided by the Swedish Institute of Space Physics (IRF). It will reveal how solar wind interacts with the lunar surface, which may help determine the process behind the formation of lunar water.
The cost of the entire mission was close to building one kilometer of subway. The cost-per-kilometer of subway in China varies from 500 million yuan (about 72.6 million U.S. dollars) to 1.2 billion yuan (about 172.4 million U.S. dollars), depending on the difficulty of construction. 
The landing site is within a crater called Von Kármán (180 km or 110 mi diameter) in the South Pole-Aitken Basin on the far side of the Moon that was still unexplored by landers. The site has symbolic as well as scientific value. Theodore von Kármán was the PhD advisor of Qian Xuesen, the founder of the Chinese space program.
Operations and results
A few days after landing, Yutu-2 went into hibernation for its first lunar night and it resumed activities on January 29, 2019 with all instruments operating nominally. During its first full lunar day, the rover travelled 120 m (390 ft), and on 11 February 2019 it powered down for its second lunar night. In May 2019, it was reported that Chang'e 4 has identified what appear to be mantle rocks on the surface, its primary objective.
In December 2019, Yutu 2 broke the lunar longevity record, previously held by the Soviet Union's Lunokhod 1 rover, which operated on the lunar surface for eleven lunar days (321 Earth days) and traversed a total distance of 10.54 km (6.55 mi).
In February 2020, Chinese astronomers reported, for the first time, a high-resolution image of a lunar ejecta sequence, and, as well, direct analysis of its internal architecture. These were based on observations made by the Lunar Penetrating Radar (LPR) on board the Yutu-2 rover while studying the far side of the Moon.
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