Tiangong-1

Tiangong-1 Target Vehicle
天宫一号目标飞行器
Model of Tiangong space lab with attached Shenzhou manned spacecraft
Plan diagram of Tiangong-1 with solar panels extended
Station statistics
COSPAR ID 2011-053A
SATCAT no. 37820
Crew 3
Launch 29 September 2011[1][2] at 21:16:03.507 CST
Carrier rocket Long March 2F/G
Launch pad Jiuquan LA-4/SLS-1
Reentry
Mission status Complete[4]
Mass 8,506 kg (18,753 lb)[6]
Length 10.4 m (34.1 ft)
Diameter 3.35 m (11.0 ft)
Pressurised volume 15 m3 (530 cu ft)[7]
Days in orbit 6 years, 185 days
Days occupied 20 days 18.5 hours [8]
Tiangong-1
Simplified Chinese 天宫一号
Traditional Chinese 天宮一號
Literal meaning Celestial Palace-1 or Heavenly Palace-1
Target Vehicle
Simplified Chinese 目标飞行器
Traditional Chinese 目標飛行器
Literal meaning Target Vehicle

Tiangong-1 (Chinese: 天宫一号; pinyin: Tiāngōng yīhào; literally: "Heavenly Palace 1" or "Celestial Palace 1") was China's first prototype space station.[9] It orbited Earth from September 2011 to April 2018, serving as both a manned laboratory and an experimental testbed to demonstrate orbital rendezvous and docking capabilities during its two years of active operational life.[10]

Launched unmanned aboard a Long March 2F/G rocket[1] on 29 September 2011,[11] it was the first operational component of the Tiangong program, which aims to place a larger, modular station into orbit by 2023.[10][12] Tiangong-1 was initially projected to be deorbited in 2013,[13] to be replaced over the following decade by the larger Tiangong-2 and Tiangong-3 modules,[14] but it orbited until 2 April 2018.[3][4][5][15][16]

Tiangong-1 was visited by a series of Shenzhou spacecraft during its two-year operational lifetime. The first of these, the unmanned Shenzhou 8, successfully docked with the module in November 2011,[17][18] while the manned Shenzhou 9 mission docked in June 2012.[19][20][21] A third and final mission to Tiangong-1, the manned Shenzhou 10, docked in June 2013.[22][23][24] The manned missions to Tiangong-1 were notable for including China's first female astronauts, Liu Yang and Wang Yaping.[23][25]

On 21 March 2016, after a lifespan extended by two years, the China Manned Space Engineering Office announced that Tiangong-1 had officially ended its service.[26][27] They went on to state that the telemetry link with Tiangong-1 had been lost.[28] A couple of months later, amateur satellite trackers watching Tiangong-1 found that China's space agency had lost control of the station.[28] In September, after conceding they had lost control over the station, officials speculated that the station would re-enter and burn up in the atmosphere late in 2017.[29][30] According to the China Manned Space Engineering Office, Tiangong-1 started reentry over the southern Pacific Ocean, northwest of Tahiti, on 2 April 2018 at 00:15 UTC.[4][5][15][16]

Design and development

The China National Space Administration (CNSA) designed Tiangong- 1 as an 8.5-tonne (19,000 lb) "space-laboratory module", capable of supporting the docking of manned and autonomous spacecraft. In 2008, the China Manned Space Engineering Office (CMSEO) released a brief description of Tiangong-1, along with its larger successor modules, Tiangong-2 and Tiangong-3. A model of the space station was revealed in the Chinese Lunar New Year celebration program on CCTV on 25 January 2009.[31]

On 29 September 2008, Zhang Jianqi (張建啟), vice-director of the CMSEO, declared in an interview with China Central Television (CCTV)[32] that Tiangong-1 would be launched in 2010 or 2011. Xinhua later stated that Tiangong-1 would be launched in late 2010, and declared that the renovation of ground equipment was in progress.[33] However, the launch did not ultimately take place until 2011.

By mid-2011, the construction of Tiangong-1 was complete, and its systems and thermal properties were undergoing testing. Testing was also conducted on the Long March 2F carrier rocket on which Tiangong-1 would be launched; technicians undertook particularly extensive safety tests on the rocket in August and September 2011,[11] following the launch failure of a Long March 2C rocket on 18 August.[34]

Structure

Tiangong-1 had a pressurised habitable volume of approximately 15 cubic metres (530 cu ft), and used passive APAS-type docking connectors.[35] Structurally, Tiangong-1 was divided into two primary sections: a resource module, which mounted its solar panels and propulsion systems, and a larger, habitable experimental module.[36]

Onboard facilities

Tiangong-1's experimental module was equipped with exercise gear and two sleep stations.[7] The interior walls of the spacecraft had a two-color paint scheme – one color representative of the ground, and the other representative of the sky. This was intended to help the astronauts maintain their orientation in zero gravity.[7] High-resolution interior cameras allowed manned missions to be closely monitored from the ground, and the two sleep stations had individual lighting controls.[37] Toilet facilities and cooking equipment for the manned missions were provided by the docked Shenzhou spacecraft, rather than being integrated into the Tiangong module itself.[37] Similarly, one member of the module's three-person crew slept in the Shenzhou spacecraft, preventing overcrowding.[37]

Mission profile

Background

Tiangong-1 was originally intended to be launched in August 2011, and was delivered to the Jiuquan Satellite Launch Center on 23 July, successfully passing a launch rehearsal test on 17 August.[38] However, following the failed launch of a Long March 2C rocket in August 2011, the launch was postponed. Following an investigation into the August launch failure,[11][39] Tiangong-1's launch was rescheduled for late September 2011,[40] partly to coincide with the Chinese National Day on 1 October.[41]

Launch

On 20 September 2011, the spacecraft was again rolled out to Pad 1 of the South Launch Site at Jiuquan in preparation for the rescheduled launch attempt.[42] The launch occurred at 13:16 UTC on 29 September, successfully placing Tiangong-1 into low Earth orbit.[38] Chinese television broadcast the launch animation accompanied by an instrumental version of the American patriotic song America the Beautiful, a choice of music for which it later offered no explanation.[43]

Orbital transfers and testing

On 30 September 2011, Tiangong-1 completed the second of two orbital transfer maneuvers, reaching an apogee altitude of 355 kilometres (221 mi)[44] . This was the precursor to a week-long program of orbital testing, conducted from the Beijing Aerospace Command and Control Center, to prepare the module for future orbital docking operations.[44] On 10 October, Tiangong-1 released its first orbital photo, showing a view of its outer hull and satellite relay antenna.[45]

Autonomous orbital docking

Diagram of Tiangong-1 (left) docked to a Shenzhou spacecraft (right).

The unmanned Shenzhou 8 mission successfully docked with Tiangong-1 on 2 November 2011 GMT, marking China's first orbital docking.[17] Shenzhou 8 undocked from Tiangong-1 on 14 November, before successfully completing a second rendezvous and docking, thus testing the reusability of the docking system.[18][46][47] Shenzhou 8 deorbited on 17 November 2011, and landed intact in Siziwang Banner in Inner Mongolia.[48] After the mission, the CNSA reported that Tiangong-1's systems were in optimal condition.[49]

Manned missions

Preparations

In December 2011, the Tiangong-1 module began automated internal checks for toxic gas, to ensure that its interior would be safe for astronauts to enter.[50] In January 2012, reports emerged alleging that the American X-37B robotic spaceplane was shadowing Tiangong-1 for surveillance purposes.[51] However, former United States Air Force orbital analyst Brian Weeden later refuted this claim, emphasizing that the X-37B occupied a different orbit from Tiangong-1, and would not be able to closely observe the module.[52]

Shenzhou 9

The three members of Shenzhou 9's crew. Liu Yang, China's first female astronaut, is shown on the right.

In March 2012, it was reported that China had finished the initial crew selection for the Shenzhou 9 mission. Niu Hongguang, the deputy chief commander of the China Manned Space Engineering Project, stated that Shenzhou 9 would dock with Tiangong-1 before August 2012.[53] The Shenzhou 9 spacecraft was delivered to Jiuquan Satellite Launch Center for launch preparations on 9 April 2012,[54] while its Long March 2F carrier rocket arrived a month later on 9 May.[55]

Shenzhou 9 launched successfully on 16 June 2012, carrying with it China's first female astronaut, Liu Yang.[19][21][25][56] The spacecraft docked with Tiangong-1 on 18 June 2012 at 14:07 Beijing time (06:07 GMT; 07:07 BST).[20] After about three hours, when the air pressures inside the two vessels were equalized, mission commander Jing Haipeng entered Tiangong-1.[57] The first docking was entirely computer-controlled, without input from the three astronauts;[20] a second, crew-guided docking was successfully conducted on 24 June 2012 at 12:42 Beijing time.[58] Shenzhou 9 landed safely in Inner Mongolia on 29 June 2012.[59] In August 2012, Shenzhou 9's crew travelled to Hong Kong to discuss their mission with university students.[60]

Shenzhou 10

Map of Tiangong-1's orbits in June 2013.

The manned Shenzhou 10 spacecraft, the final Shenzhou mission to rendezvous with Tiangong-1 before its deorbit, was launched on 11 June 2013.[22][23][61] The launch of Shenzhou 10 was originally planned for earlier in the year, but was delayed to allow the mission to incorporate more complex scientific experiments.[62] The mission's crew included China's second female astronaut, Wang Yaping.[23] Shenzhou 10 docked successfully with Tiangong-1 on 13 June.[24]

On 15 June 2013, the Shenzhou 10 crew completed China's first orbital maintenance operation, replacing Tiangong-1's interior cladding.[63] Additional maintenance work was conducted on the space station's seal rings.[63] On 20 June, Wang Yaping delivered a remote video lecture from orbit to students across China, demonstrating physics in microgravity with her colleagues.[64] On 24 June, CPC general secretary Xi Jinping contacted the astronauts via remote video link to congratulate them.[65] After a series of successful docking tests, Shenzhou 10 undocked and returned safely to Earth on 26 June 2013.[66] With a duration of 15 days, Shenzhou 10 was China's longest manned space mission,[67] until Shenzhou 11's 30-day mission to Tiangong-2 in 2016.[68]

Post-mission

The Tiangong-1 was launched in September 2011, with an intended service span of two years. After the last crew departed the module in June 2013, it was put into sleep mode. It was intended that it would remain in orbit for some time, allowing China to collect data on the longevity of key components before being commanded to gradually re-enter the atmosphere. The Permanent Mission of China to the United Nations informed the Committee on the Peaceful Use of Outer Space that the Tiangong-1 had ceased functioning on 16 March 2016.[69] On 21 March 2016, the Manned Space Engineering Office announced that they had disabled data service, since the space station had operated two-and-a-half years longer than its intended two-year service plan. According to the office, the space laboratory was under continued and close monitoring until it finally burned up in the Earth's atmosphere during an uncontrolled re-entry.[26][27]

Re-entry

Map showing the probability of re-entry of Tiangong 1 by latitude. Latitudes shaded red were most likely; latitudes shaded green were least likely. Areas outside possible re-entry latitudes are not pictured.[70]

The orbit of Tiangong-1 was decaying gradually, and the space laboratory was predicted to be destroyed upon re-entry into Earth's atmosphere.[71][72][73]

At the request of China and the United Nations Office for Outer Space Affairs, the Inter-Agency Space Debris Coordination Committee (IADC), led by the European Space Agency (ESA), conducted an international campaign to monitor the re-entry of Tiangong-1. ESA's Space Debris Office in Darmstadt, Germany hosted and administered the campaign, with participation from other space agencies and organizations including the China National Space Administration, the Indian Space Research Organisation, the Japan Aerospace Exploration Agency, the Korea Aerospace Research Institute, and Roscosmos.[74] The IADC predicted that Tiangong-1 would break up during re-entry, but that parts of the station would survive and fall to the Earth's surface, potentially falling across an area thousands of kilometres long and tens of kilometres wide. However, because most of the re-entry area was ocean or uninhabited land, the IADC stated that the odds of a person being hit by falling debris to be "10 million times smaller than the yearly chance of being hit by lightning."[70] The IADC's final prediction before re-entry was that Tiangong-1 would re-enter at around 01:00 UTC on 2 April 2018, plus or minus 2 hours, falling somewhere on Earth between 42.8° North and 42.8° South latitudes,[75][76] with the most likely re-entry sites being at the north and south extremes of that range. This is because the station's high-inclination orbit had the smallest north-south speed at the extreme latitudes, and the greatest north-south speed near the Equator.[70]

Independently, the non-profit Aerospace Corporation's Center for Orbital and Re-entry Debris Studies (CORDS) predicted that Tiangong-1 would most likely re-enter the atmosphere around 00:30 UTC on 2 April 2018, plus or minus 1.7 hours. CORDS scientists also predicted that it would re-enter somewhere between the 42.7° North and 42.7° South latitudes, a range that covered two-thirds of the Earth's surface, with a high likelihood of an ocean landing of whatever did not burn up during re-entry.[77] They predicted that if any parts of the station survived re-entry, the small amount of debris would impact the ground over an area a few hundred square kilometers in size.[78] The final prediction of likely areas for debris impact covered southern South America, Africa, the Middle East, and central Asia.[78][79] However, even in those high-probability areas, they still estimated the odds of a specific person being hit by debris to be "about one million times smaller than the odds of winning the Powerball jackpot."[80]

Tiangong-1 reentered the Earth's atmosphere at approximately 00:16 UTC on 2 April 2018 over the South Pacific Ocean at 24°30′S 151°06′W / 24.5°S 151.1°W / -24.5; -151.1.[4][78] According to Chinese state news agency Xinhua, the station mostly burnt up upon re-entry.[81] It was the largest spacecraft to re-enter the atmosphere since Fobos-Grunt in January 2012.[70] This was about 3,600 kilometres (1,900 nmi) from Point Nemo, a location often used as a spacecraft cemetery to crash defunct satellites.[82] As the spacecraft made an uncontrolled reentry, this was unintended coincidence.

Altitude of Tiangong-1 from March 2017[83]
Final orbit above the Pacific Ocean with 1 minute markers

Program developments

Tiangong-1 was designed as a test bed for key technologies later used on another test station called Tiangong-2, which was launched on 15 September 2016.[84] Both experimental space stations are short-lived and meant to test technologies and systems for a permanent future space station called Chinese large modular space station, which is planned to be assembled from 2019 to 2022.[85]

The design of Tianzhou, an automated cargo spacecraft intended to resupply the Chinese large modular space station, is based on Tiangong-1.[14][86]

See also

References

  1. 1 2 "China to launch unmanned space module by Sept 30". SpaceDaily.com. Retrieved 29 September 2011.
  2. ↑ "Insider: Tiangong 1 to launch in early Sept". Beijing Times. 24 August 2011. Retrieved 1 September 2011.
  3. 1 2 "Tracking and Impact Prediction". Space-Track.Org. JFSCC/J3. 1 April 2018. Retrieved 1 April 2018.
  4. 1 2 3 4 5 Chiles, Cody (1 April 2018). "JFSCC tracks Tiangong-1's reentry over the Pacific Ocean". Vandenberg Air Force Base (Press release). Retrieved 3 April 2018. U.S. Strategic Command’s (USSTRATCOM) Joint Force Space Component Command (JFSCC), through the Joint Space Operations Center (JSpOC), confirmed Tiangong-1 reentered the Earth’s atmosphere over the southern Pacific Ocean at approximately 5:16 p.m. (PST) April 1, 2018.
  5. 1 2 3 "Tiangong-1 reenters the atmosphere". cmse.gov.cn. China Manned Space. 2 April 2018. Retrieved 2 April 2018.
  6. ↑ 天宫一号任务飞行方案. (PDF, in Chinese). Retrieved 30 September 2011.
  7. 1 2 3 Xin, Dingding (27 September 2011). "Spacecraft ready to go on mission". China Daily. Retrieved 27 September 2011.
  8. ↑ Hatch open to hatch closed: Jonathan McDowell (April 4, 2018). "Tiangong 1 statistic discussions". Twitter.
  9. ↑ "China launches Tiangong-1 to mark next human space flight milestone". NASASpaceflight.com. 28 September 2011. Retrieved 22 October 2011.
  10. 1 2 David, Leonard (11 March 2011). "China Details Ambitious Space Station Goals". Space.com. Retrieved 4 November 2013. China is ready to carry out a multiphase construction program that leads to a large space station around 2020. As a prelude to building that facility, China is set to loft the Tiangong-1 module this year as a platform to help master key rendezvous and docking technologies.
  11. 1 2 3 "Spacecraft Tiangong-1 launch delayed". China Daily. 2 September 2011. Retrieved 14 September 2011.
  12. ↑ "China to launch space station by 2023". BBC. 26 September 2013. Retrieved 1 October 2013.
  13. ↑ "China to launch module for future space station" (PDF). PhysOrg.com. 28 September 2011. Retrieved 10 March 2013.
  14. 1 2 "China to launch Tiangong-2 and cargo spacecraft in 2015". GB Times. 13 June 2013. Retrieved 16 June 2013.
  15. 1 2 Staff (1 April 2018). "Tiangong-1: Defunct China space lab comes down over South Pacific". BBC News. Retrieved 1 April 2018.
  16. 1 2 Chang, Kenneth (1 April 2018). "China's Tiangong-1 Space Station Has Fallen Back to Earth Over the Pacific". The New York Times. Retrieved 1 April 2018.
  17. 1 2 "Chinese spacecraft dock in orbit". BBC. 2 November 2011. Retrieved 15 June 2013.
  18. 1 2 "China completes second space docking". AFP via Google. 14 November 2011. Retrieved 15 November 2011.
  19. 1 2 "China launches space mission with first woman astronaut". BBC. 16 June 2012. Retrieved 4 November 2013.
  20. 1 2 3 "Shenzhou-9 docks with Tiangong-1". BBC. 18 June 2012. Retrieved 4 November 2013.
  21. 1 2 "China to carry out manned space flight". BBC. 9 June 2012. Retrieved 26 October 2012.
  22. 1 2 "China to launch next manned spaceship in 2013". BBC. 10 November 2012. Retrieved 4 November 2013.
  23. 1 2 3 4 "Shenzhou-10: China launches next manned space mission". BBC. 11 June 2013. Retrieved 11 June 2013.
  24. 1 2 "Shenzhou-10: Chinese capsule docks with space laboratory". BBC. 13 June 2013. Retrieved 13 June 2013.
  25. 1 2 "China sends its first female astronaut into space". The Daily Telegraph. 16 June 2012. Retrieved 4 November 2013.
  26. 1 2 "天宫一号正式终止数据服务 全面完成各项在轨试验任务-新华网" (in Chinese). Xinhua News Agency. Retrieved 9 April 2016.
  27. 1 2 "China's 1st space lab Tiangong-1 ends data service". Space Daily. Beijing: Space Media Network. 23 March 2016. Retrieved 29 March 2018.
  28. 1 2 Jones, Morris (30 March 2016). "Has Tiangong 1 gone rogue". Space Daily. Retrieved 22 September 2016.
  29. ↑ "China's Tiangong-1 to fall to Earth late 2017", Xinhua News Agency, China, 14 September 2016. Retrieved 22 September 2016.
  30. ↑ Guarino, Bin (21 September 2016). "Out of control? China's Tiangong 1 space station will fall to Earth – somewhere – in 2017". The Washington Post. Retrieved 22 September 2016.
  31. ↑ 天宫一号"空间站已进入初样研制阶段(图) (in Chinese). CCTV. 25 January 2009. Retrieved 26 July 2013.
  32. ↑ 我国将于2010年-2011年发射小型空间站 (in Chinese). Sina.com. 29 September 2008. Retrieved 26 July 2013.
  33. ↑ "Unmanned space module to be launched in 2010, await space docking". Xinhuanet. 28 February 2009. Archived from the original on 8 November 2012. Retrieved 30 September 2011.
  34. ↑ "Malfunction at devices connection blamed for orbiter launch failure". Xinhua News Agency. 6 September 2011. Retrieved 9 August 2015.
  35. ↑ "China Accelerates Manned Space Program with Tiangong Docking Module and Advanced Shenzhou". AmericaSpace. 23 September 2011. Retrieved 3 November 2011.
  36. ↑ "China Launches Tiangong-1 Space Lab". InterSpace News. 29 September 2011. Retrieved 3 November 2011.
  37. 1 2 3 "Living on Tiangong". SpaceDaily.com. 25 October 2011. Retrieved 29 October 2011.
  38. 1 2 Barbosa, Rui (28 September 2011). "China launches TianGong-1 to mark next human space flight milestone". NASASpaceflight.com. Retrieved 5 January 2013.
  39. ↑ Moskowitz, Clara (14 September 2011). "China's space dreams ride on robotic docking success". MSNBC. Retrieved 30 September 2011.
  40. ↑ "China Readies for Own Space Station in Test Launch" Archived 25 September 2011 at the Wayback Machine.. International Business Times. 21 September 2011. Retrieved 30 September 2011.
  41. ↑ "SPACE: 'Heavenly Palace' heads into space". Business Day.South Africa 21 September 2011. Retrieved 30 September 2011.
  42. ↑ "China set to 'Leap Forward in Space' as Tiangong 1 Rolls to Launch Pad". Universe Today. 26 September 2011. Retrieved 30 September 2011.
  43. ↑ Murray, Warren (30 September 2011). "Rocket's red glaring error: China sets space launch to America the Beautiful". The Guardian. Retrieved 30 September 2011.
  44. 1 2 "天宫一号成功完成二次变轨" (in Chinese). People's Daily. 1 October 2011. Retrieved 21 November 2011.
  45. ↑ "Tiangong 1 releases first photo in space". People's Daily. 12 October 2011. Retrieved 18 October 2011.
  46. ↑ "2nd docking of Tiangong-1 & Shenzhou-8 on schedule". Archived 10 November 2011 at the Wayback Machine. Xinhua. 7 November 2011. Retrieved 15 June 2013.
  47. ↑ "Chinese spacecraft Shenzhou-8 disengages from space lab module Tiangong-1". Xinhua. 14 November 2011. Retrieved 15 June 2013.
  48. ↑ "Shenzhou 8 Docking Mission Major Step To Space Station, China Says". HuffPost. 18 November 2011. Retrieved 4 November 2013.
  49. ↑ "China plans major effort in pursuing manned space technology". SpaceDaily.com. 22 November 2011. Retrieved 23 November 2011.
  50. ↑ "Tiangong-1 orbiter starts planned cabin checks against toxic gas". SpaceDaily.com. 19 December 2011.
  51. ↑ "US 'space warplane' may be spying on Chinese spacelab". The Register. 6 January 2012. Retrieved 13 January 2012.
  52. ↑ "Expert: U. S. Secret Space Plane Not Likely 'Spying' on China Module" Archived 11 January 2012 at the Wayback Machine.. International Business Times. 9 January 2012. Retrieved 13 January 2012.
  53. ↑ "Shenzhou-9 may take female astronaut to space". SpaceDaily.com. 14 March 2012. Retrieved 24 March 2012.
  54. ↑ "Shenzhou-9 spacecraft delivered to launch center". China Daily. 9 April 2012. Retrieved 24 April 2012.
  55. ↑ "Launch preps begin for next Chinese human spaceflight". Spaceflight Now. 14 May 2012. Retrieved 24 May 2012.
  56. ↑ "China to send first woman astronaut Liu Yang into space". BBC. 15 June 2012. Archived from the original on 13 December 2017. Retrieved 4 November 2013.
  57. ↑ "China successfully completes space docking". China Daily. 19 June 2012. Retrieved 4 November 2013.
  58. ↑ "Video: China's first manual space docking". People's Daily. 24 June 2012. Retrieved 4 November 2013.
  59. ↑ "China's Shenzhou 9 spacecraft returns to earth". The Guardian. 29 June 2012. Retrieved 4 November 2013.
  60. ↑ "Astronauts share feelings with HK students". China Daily. 13 August 2012. Retrieved 1 September 2012.
  61. ↑ "Tiangong 1 Parked And Waiting As Shenzhou 10 Mission Prep Continues". SpaceDaily.com. 5 November 2012. Retrieved 9 November 2012.
  62. ↑ "Reshuffle for Tiangong". SpaceDaily.com. 23 January 2013. Retrieved 12 February 2013.
  63. 1 2 "Astronauts complete first maintenance on Tiangong-1". China Daily. 15 June 2013. Retrieved 19 June 2013.
  64. ↑ "China gives first lecture from space". BBC. 20 June 2013. Retrieved 21 June 2013.
  65. ↑ "China poised for bigger strides in space exploration: Xi Jinping". Zee News. 24 June 2013. Retrieved 26 June 2013.
  66. ↑ "China's Shenzhou-10 mission successful". Xinhua News Agency. 26 June 2013. Retrieved 26 June 2013.
  67. ↑ "China launches Shenzhou-10 manned space mission". The Telegraph. 11 June 2013. Retrieved 11 June 2013.
  68. ↑ SCIO briefing on China's Tiangong 2 and Shenzhou 11 manned space mission China.org.cn 19 November 2016
  69. ↑ "Note verbale dated 4 May 2017 from the Permanent Mission of China to the United Nations (Vienna) addressed to the Secretary-General" (PDF). UN Office for Outer Space Affairs. 4 May 2017.
  70. 1 2 3 4 "Tiangong-1 frequently asked questions". Rocket Science Blog. European Space Agency. 16 January 2018. Retrieved 11 March 2018.
  71. ↑ David, Leonard (10 June 2016). "When Will China's 'Heavenly Palace' Space Lab Fall Back to Earth?". Space.com. Retrieved 15 July 2016.
  72. ↑ Howell, Elizabeth (13 July 2016). "Tiangong-1: China". Space.com. Retrieved 15 July 2016.
  73. ↑ Malkin, Bonnie (6 March 2018). "China's Tiangong-1 space station will crash to Earth within weeks". The Guardian. Archived from the original on 6 March 2018. Retrieved 6 March 2018.
  74. ↑ "ESA joins re-entry campaign" (Press release). European Space Agency. 6 November 2017. Retrieved 15 March 2018.
  75. ↑ "Tiangong-1 Reentry Updates". Rocket Science Blog. European Space Agency. 1 April 2018. Retrieved 1 April 2018.
  76. ↑ "→Monitoring (almost) complete". Rocket Science Blog. European Space Agency. 1 April 2018. Retrieved 1 April 2018.
  77. ↑ Moser, Dave (3 January 2018). "China's out-of-control space station may crash to Earth in 2 months". Business Insider. Retrieved 3 January 2018.
  78. 1 2 3 "Tiangong-1 Reentry". Center for Orbital and Reentry Debris Studies. The Aerospace Corporation. 2 April 2018. Retrieved 2 April 2018.
  79. ↑ Grush, Loren (26 March 2018). "China's spiraling space station will plunge to Earth in about a week". The Verge. Retrieved 1 April 2018. And once it gets down to plus or minus six hours, you can start ruling out continents.
  80. ↑ "Tiangong-1 Reentry". Center for Orbital and Reentry Debris Studies. The Aerospace Corporation. 20 March 2018. Archived from the original on 22 March 2018. Retrieved 22 March 2018. The map below shows the relative probabilities of debris landing within a given region. Yellow indicates locations that have a higher probability while green indicates areas of lower probability. Blue areas have zero probability of debris reentry since Tiangong-1 does not fly over these areas (north of 42.7° N latitude or south of 42.7° S latitude). These zero probability areas constitute about a third of the total Earth's surface area.
  81. ↑ "Tiangong-1 Reentry". The Guardian. Retrieved 22 March 2018. China's Tiangong-1 space station has crashed in the Pacific Ocean, according to the country's space agency.The spacecraft re-entered the earth's atmosphere at 0015 GMT on Monday over the South Pacific and mostly burnt up on re-entry, state news agency Xinhua said.
  82. ↑ Specktor, Brandon (2 April 2018). "The Chinese Space Station Narrowly Missed Landing in the World's Largest 'Spacecraft Cemetery'". Live Science. Purch. Retrieved 3 April 2018.
  83. 1 2 "Tiangong-1 Orbital Status". Official Website of China Manned Space. China Manned Space Engineering Office. 1 April 2018. Retrieved 1 April 2018.
  84. ↑ de Selding, Peter B. (20 June 2016). "China prepares assembly of its space station, invites collaboration through U.N." Space News.
  85. ↑ "China to begin construction of manned space station in 2019". reuters.com. Reuters. Retrieved 3 April 2018.
  86. ↑ Clark, Stephen (20 April 2017). "First supply ship for Chinese space station lifts off on test flight". Spaceflight Now. Pole Star Publications Ltd. Retrieved 29 March 2018.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.