Jade Bunny (Rover)

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1: 1 scale model of Jade Bunny at an exhibition in Qingdao , 2018

Jadehase or Yutu ( Chinese  玉兔號月球車  /  玉兔号月球车 , Pinyin Yùtùhào yuèqiúchē  - "Jadehase Moon vehicle," short 玉兔號  /  玉兔号 , Yùtùhào ) is a six-wheeled lunar rover , which at the Mission 3 Chang'e- of China National Space Administration (CNSA) was dropped on the moon as part of the People's Republic of China's lunar program .

Jade Hare was launched on December 1, 2013 at 17:30 UTC and reached the surface of the moon on December 14, 2013. This was the first soft landing on the moon since 1976 and the first use of a lunar rover since Lunochod 2 on May 11, 1973 went out of order. The vehicle was dropped off the Chang'e-3 lander and explored the surface of the moon independently.

The rover suffered operational difficulties after six weeks after surviving the first 14-day lunar night. After the second lunar night he was unable to move, but was still able to collect useful data from his now fixed position. In October 2015, it exceeded the previous record for the longest operating life of a moon rover. On July 31, 2016, Jadehase ceased operations after a total of 31 months, which was significantly longer than its expected service life of three months.

In January 2019, the successor to this moon rover, Jadehase 2 , was used on the back of the moon as part of the Chang'e-4 mission.

History of the mission

Already since 1998, four years after the moon exploration project group of the Chinese Academy of Sciences had submitted the first feasibility study for a lunar exploration program, around a dozen research institutes had been working on prototypes for a moon rover. For example, the model of the computer science faculty at Tsinghua University in Beijing had six individually driven wheels and was able to take samples of helium-3 in addition to the heating of soil samples and their spectrographic examination . In the end, however, the Rover, developed under the leadership of the 5th Research Institute of the China Aerospace Science and Technology Corporation , now known as the " Chinese Academy for Space Technology ", was awarded the contract.

The rover's name was chosen in an online poll and subsequent vote by 3,445,248 Chinese at home and abroad. In Chinese mythology, the word jade hare ( 玉兔 , yùtù ) describes the companion of the moon goddess Chang'e (see hare in the moon ).

Mission objectives

The official goal of the mission was China's first soft landing and China's first use of a rover on the moon, as well as developing and testing key technologies for future missions.

The scientific goals of Chang'e-3 mainly included the exploration of the lunar surface topography, the composition of the surface material, the detection of the spatial environment (sun-earth-moon) as well as astronomical observations from the lunar surface. Chang'e-3 made the first direct radar measurement of the structure and depth of the lunar regolith to a depth of 30 meters, and the structure of the lunar crust to a depth of several hundred meters.

Structure of the rover

Unlike NASA and ESA , the CNSA does not reveal much of its missions to the public. Therefore, information about Jade Bunny is limited as well.

The rover is around 1.5 meters high, weighs 140 kilograms and can carry 20 kilograms of payload. It is smaller than the Mars Exploration Rover Spirit and Opportunity . Its instruments include two navigation cameras , two panorama cameras , two collision avoidance cameras , ground penetrating radar , an infrared spectrometer and an alpha particle X-ray spectrometer (APXS). Jadehase has a robotic arm to position his APXS close to a soil sample. The rover was also able to transmit video images live and was equipped with automatic sensors that prevent collisions with other objects. Each of the three pairs of cameras could be used for stereoscopic images as well as for distance measurements by means of triangulation .

Jade Rabbit was designed to explore an area of ​​3 square kilometers during a three month mission, with a maximum driving distance of 10 kilometers. It received its energy from two solar panels that enabled it to operate during the 14-day lunar days. During the 14-day lunar nights, the rover went into standby mode . In doing so, he received heat from radionuclide heating elements with plutonium 238 Pu and two-phase liquid loops.

Course of the mission

Galileo image with the landing position of Chang'e-3
LRO image with the landing site on the border between darker and lighter basalt soil
LRO picture from December 25th 2013 with the lander (big arrow) and the rover (small arrow)

Chang'e-3 landed north of the Mare Imbrium on December 14, 2013 and dropped the rover Yutu 7 hours and 24 minutes later, at 20:35 UTC.

First lunar day

The first task that Jadehase fulfilled by December 22, 2014 was to photograph the lander from different angles, while the other way around it was also filmed and photographed from the lander. A number of these images have been published.

For the first moonlit night, the rover moved about 40 meters south of the lander. On December 25th the lander and on December 26th the rover went into energy-saving standby mode.

Second lunar day

On January 11, 2014, the rover woke up from standby and carried out its first inspection of the lunar soil by January 16. On January 25, 2014, six weeks after the rover began and near the end of the second lunar day, China's state media announced that Jade Rabbit had a "mechanical control abnormality" caused by the "complicated lunar surface environment." The Planetary Society reported that the rover did not respond correctly to commands from Earth, which meant that it could not be properly prepared for the coming lunar night. It later became clear that Jadehase had suffered a control circuit malfunction in his landing gear, which prevented him from adopting his normal "sleeping position" (folding the mast and solar panels).

Third lunar day

On February 12, 2014, the control center was initially unable to communicate with Yutu and therefore declared him permanently inoperative. On February 13, the rover unexpectedly contacted the control center. Chinese Lunar Program spokesman Pei Zhaoyu said that although Jade Rabbit was able to communicate, it was still immobile due to its "mechanical control abnormality."

On February 22, 2014, the rover entered its third standby phase. Chinese space scientists eventually said that while Yutu was immobile, the ground penetrating radar, panoramic cameras, and infrared spectrometer were operational.

Further course

On April 18, 2014, Wang Jianyu of the Chinese Society of Space Research (CSSR) said that the disturbance was not mechanical but electrical and that work around it was being tried. He also stated that the temperature on the moon was significantly lower than previously estimated and that certain components may have suffered frost damage. Because the solar panels could not be folded into the "sleeping position", they could not be used as intended to insulate the electronics during the moonlit night.

Although the scientific instruments still worked, their usefulness was clearly limited as the rover could no longer change its position.

On August 3, 2016, it was reported that despite repeated attempts, Jadehase could no longer establish communication with Chang'e-3, which meant the practical end of the mission.

Yutu has covered a total of 114 meters on the moon.

Web links

Commons : Jadehase  - Collection of images, videos and audio files

Individual evidence

  1. ↑ Leonard David: China Reading 1st Moon Rover for Launch This Year. space.com, June 19, 2013, accessed July 19, 2013 .
  2. ↑ Space travel: Chinese probe is scheduled to land on the moon in 2013. spiegel.de, August 29, 2013, accessed on August 29, 2013 .
  3. ↑ China lands Jade Rabbit robot rover on Moon , BBC. December 14, 2013. 
  4. ↑ a b László Molnár: Chang'e-3 revealed - and its massive! . In: Pull Space Technologies , May 24, 2013. 
  5. ↑ a b China's first moon rover has experienced a "mechanical control abnormality" , Australian Broadcasting Corporation. January 26, 2014. 
  6. ^ Alan Boyle: Chinese moon lander and rover wake up after weeks of sleep , NBC News. January 12, 2014. 
  7. ↑ a b Euan McKirdy: Down but not out: Jade Rabbit comes back from the dead . In: CNN , February 13, 2014. 
  8. ↑ Jeff Foust: China's Immobile Rover Passes a Purely Figurative Milestone , SpaceNews. October 30, 2015. 
  9. ↑ 张晓娟 、 熊 峰: 中国 月球 车 在 秘密 研制 中 权威人士 透露 有关 详情. In: http://news.sina.com.cn . October 20, 2002, accessed May 1, 2019 (Chinese).
  10. ↑ 李莎莎: 中国 月球 车 制造 完毕 2013 年 有望 探 月. In: http://news.163.com . April 10, 2010, accessed May 1, 2019 (Chinese).
  11. ↑ 嫦娥 三号 月球 车 命名 “玉兔 号” 经 全球 征 名 产生. In: http://www.chinanews.com . November 26, 2013, accessed May 1, 2019 (Chinese).
  12. ↑ a b c Sun Zezhou , Jia Yang and Zhang He: Technological advancements and promotion roles of Chang'e-3 lunar probe mission. In: link.springer.com. September 28, 2013, accessed December 12, 2019 .
  13. ↑ 欧阳自远 ： 嫦娥 三号 明年 发射 将 实现 着陆 器 与 月球 车 联合 探测 (Chinese) , Xinhua. June 14, 2012. 
  14. ↑ Srinivas Laxman: Chang'e-3: China To Launch First Moon Rover In 2013 . In: Asian Scientist , March 7, 2012. 
  15. ↑ Zhao Lei: Most Chang'e-3 science tools activated . In: ChinaDaily . 18th December 2013.
  16. ↑ China considering manned lunar landing in 2025–2030 . May 24, 2009. 
  17. ↑ Chang'e 3 . SPACEFLIGHT101. Retrieved December 2, 2013.
  18. ↑ Su Yan, Fang Guangyou et al .: Data processing and initial results of Chang'e-3 lunar penetrating radar. In: iopscience.iop.org. September 13, 2014, accessed March 15, 2020 .
  19. ↑ Fang Guangyou et al .: Lunar Penetrating Radar onboard the Chang'e-3 mission. In: iopscience.iop.org. September 29, 2014, accessed March 15, 2020 .
  20. ↑ zh: "嫦娥 三号" 发射 成功 将于 5 天后 到达 月球 ( Chinese ) Netease. paragraph "月 兔" 将 巡天 观 地 测 月. 2nd December 2013.
  21. ↑ Emily Lakdawalla: Chang'e 3 update with lots of pictures: Yutu begins lunar journey . The Planetary Society. December 23, 2013.
  22. ↑ Moon rover Yutu sleeps as night comes , ChinaDaily. December 26, 2013. 
  23. ^ Ralph L. McNutt Jr .: Radioisotope Power Systems: Pu-238 and ASRG status and the way forward . Johns Hopkins University . January 2014.
  24. ↑ Ian O'Neil: China's Rover Rolls! Yutu Begins Moon Mission . In: Discovery News , CCTV, December 14, 2013. 
  25. ↑ Emily Lakdawalla: Bad news for Yutu rover . In: Planetary Society , January 25, 2014. 
  26. ↑ Wilfred Chan: China's imperiled Jade Rabbit moon rover: 'Goodnight, humanity' , CNN. January 28, 2014. 
  27. ↑ Frances Perraudin: Beijing, we have a problem: China's first lunar rover, Jade Rabbit, signs off . In: The Guardian , Jan. 27, 2014. 
  28. ↑ David Shukman: China Moon rover Jade Rabbit in trouble . In: BBC News , BBC, January 27, 2014. 
  29. ↑ Staff: China Exclusive: Control circuit malfunction troubles China's Yutu . In: Xinhua , March 3, 2014. Archived from the original on March 9, 2014. 
  30. ↑ Emily Lakdawalla: Brief Yutu update: Slightly more detail on what's keeping rover from roving . In: The Planetary Society , March 3, 2014. 
  31. ↑ Jade Rabbit rover 'declared dead' . In: BBC News , February 12, 2014. 
  32. ↑ China's Jade Rabbit lunar rover 'could be saved' . In: BBC , February 13, 2014. 
  33. ↑ Katie Collins: It's alive! Welcome back, Jade Rabbit . In: Wired . February 13, 2014. Archived from the original on March 5, 2016.
  34. ↑ Emily Lakdawalla: Possible hope for Yutu: "Situation is getting better," but no details [UPDATED ] . The Planetary Society. 12th of February 2014.
  35. ↑ a b Ken Kremer: Yutu Moon Rover Starts 3rd Night Time Hibernation But Technical Problems Persist . In: Universe Today , February 23, 2014. 
  36. ↑ Wang Cong: China Focus: Uneasy rest begins for China's troubled Yutu rover . In: Renmin Ribao , February 23, 2014. 
  37. ↑ Xinhua: Moon rover wakes up . In: Global Times , March 14, 2014. Archived from the original on March 15, 2014. 
  38. ↑ Chen, Stephen, Last-ditch efforts to salvage mission of China's knitting Jade Rabbit lunar rover , South China Morning Post , April 18, 2014.
  39. ^ Jacob Aron: China's Jade Rabbit moon rover dead after 31 months on surface , New Scientist. August 3, 2016. Retrieved August 5, 2016. 
  40. ↑ Stephen Clark: China's Yutu rover dies on the moon , Spaceflight Now. August 4, 2016. Retrieved August 5, 2016. 
  41. ^ Mike Wall: The Moon's History Is Surprisingly Complex, Chinese Rover Finds. On: space.com. March 12, 2015.
Jade rabbit (alternative names of the lemma)
Jade bunny; Yutu; 玉兔 , yùtù ; Jade Rabbit, Chang'e 3 rover; Jade rabbit