Unha

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Unha
Unha-2.jpeg
Unha-2
Function Expendable carrier rocket
Manufacturer Korean Committee of Space Technology
Country of origin North Korea
Size
Height 32.01 metres (105.0 ft)[citation needed]
Diameter 2.41 metres (7 ft 11 in)[citation needed]
Mass 85,000 kilograms (187,000 lb)[citation needed]
Stages 3
Launch history
Status Active
Launch sites Sohae, Tonghae
Total launches 3
Successes 1
Failures 2
First flight 5 April 2009[1]
First stage
Engines 4 Nodong 2-1[2]
Thrust 1100 kN[2]
Specific impulse 252 sec[3]
Burn time 120 seconds[3]
Fuel IRFNA / UDMH
Second stage
Engines unknown[2]
Thrust 250 kN[citation needed]
Specific impulse 255 s[3]
Burn time 110 seconds[3]
Fuel IRFNA / UDMH
Third stage
Engines unknown[2]
Thrust 54 kN[citation needed]
Specific impulse 230 sec[3]
Burn time 40 seconds[3]
Fuel unknown
Unha
Chosŏn'gŭl
Hancha
Revised Romanization Eunha
McCune–Reischauer Ŭnha

The Unha or Eunha (Korean: 은하, 銀河, "Galaxy")[4] is a North Korean expendable carrier rocket, which partially utilizes the same delivery system as the Taepodong-2 long-range ballistic missile.[5]

History[edit]

North Korea's first orbital space launch attempt occurred on August 31, 1998 and was unsuccessful. This launch attempt was performed by a Paektusan rocket. The particular vehicle used in the first attempt was named the Taepo Dong 1. It used a solid motor third stage, a Scud-missile-based second stage, and a Rodong-1 based first stage. Rodong-1 was a North Korean-developed stage thought to be a scale-up of the old Soviet Scud missile. TaepoDong 1 stood 22.5 metres tall, was 1.8 metres in diameter, and weighed about 21 tonnes.

The next launch vehicle, the Unha-2, is believed to be a three-stage rocket derived from North Korea's Taepodong-2 ballistic missile - a missile that first flew, unsuccessfully, in 2006. The rocket failed after 40 seconds. TaepoDong 2's new first stage is thought to be powered by four engines, one of which powered the country's earlier Taepo Dong 1 first stage. The four engines may produce 112 tonnes-force (1,100 kN) of liftoff thrust, sufficient to rapidly lift the 78 tonne carrier rocket.[6] According to Japanese reports, the second stage splashed down in the Pacific Ocean approximately 3,200 kilometers from the launch site.[7]

The January 3, 2013 internet edition of the Rodong Sinmun, the Workers' Party official newspaper, quoted a scientist saying there would be six more satellite launch vehicles. Reports say the Unha 4 and 5 are intended to launch earth observation satellites, Unha 6, 7 and 8 would presumably place into orbit communications satellites and Unha 9 would carry a lunar orbiter.[8]

Vehicle description[edit]

Model of a Unha-9 rocket on display at a floral exhibition in Pyongyang.

The Unha's first stage consists of four clustered Nodong motors, which themselves are enlarged Scud motors. The second stage was initially thought to be based on the SS-N-6, although it is now believed to be based on Scud technology.[2] The third and last stage might be identical to the Iranian Safir's second stage which is propelled by two small gimballed motors.[2][9]

Recent satellite images of the Sohae Satellite Launching Station showing an enlarged launch tower under construction indicate that an enlarged version, called Unha-X, might be under development, coupled with a North Korean propaganda poster showing such a vehicle.[10]

Launch history[edit]

On 24 February 2009, North Korea announced that a Unha rocket would be used to launch the Kwangmyŏngsŏng-2 satellite.[11] According to the South Korean government, the launch took place on 5 April[12] from the Tonghae Satellite Launching Ground in Hwadae county.[13] Several countries, including South Korea, the U.S.A., and Japan, voiced concerns that the launch would violate United Nations Security Council Resolution 1718 which prohibits North Korea from testing ballistic missiles.[14] Russia also announced they urged North Korea to refrain from its planned rocket launch.[15]

On April 5, 2009 the Unha-2 rocket was launched at around 02:30 hours UTC (11:30 hours KST).[16] The U.S Northern Command said that the first stage of the rocket fell into the Sea of Japan (East Sea of Korea), while the other rocket stages as well as the payload fell into the Pacific Ocean, and no object entered orbit.[17][18] Later analysis indicated the rocket impacted 2,390 miles (3,850 km) from the launch site, and that the second stage operated normally but the rocket's third stage failed to separate properly.[19] North Korea maintains that the rocket successfully put its payload in orbit.[20]

On December 12, 2012, the Unha-3 rocket was launched at 00:49 UTC (7:49 EST).[21] The U.S Northern Command said that the first stage of the rocket fell into the Yellow Sea, while the debris of the second stage was assessed to have fallen into the Philippine Sea and confirmed that an object had entered orbit.[22]

Designation Date Launch Site Payload Remarks
Unha-2 5 April 2009 Tonghae North Korea Kwangmyŏngsŏng-2 Failed to reach orbit[23]
Unha-3 13 April 2012 Sohae North Korea Kwangmyŏngsŏng-3 Failed early in flight[24]
Unha-3 Unit-2 12 December 2012[25][26] Sohae North Korea Second version of Kwangmyŏngsŏng-3[27] Successful launch. S.Korea military official cited 3 stage success. DPRK confirmed[28]

See also[edit]

References[edit]

  1. ^ Krebs, Gunter. "Unha ("Taepodong-2")". Gunter's Space Page. Retrieved 19 April 2012. 
  2. ^ a b c d e f David Wright (22 February 2013). "Markus Schiller's Analysis of North Korea's Unha-3 Launcher". All Things Nuclear. Union of Concerned Scientists. Retrieved 7 March 2013. 
  3. ^ a b c d e f David Wright (March 20, 2009). "An Analysis of North Korea's Unha-2 Launch Vehicle" (PDF). Union of Concerned Scientists. Retrieved January 23, 2013. 
  4. ^ Kim, Jack (2009-03-13). "FACTBOX: North Korea's Taepodong-2 long-range missile". Reuters. Retrieved 2009-03-30. 
  5. ^ "North Korea positions rocket for April liftoff". AP. 2009-03-27. Archived from the original on 2009-03-29. Retrieved 2009-03-28. 
  6. ^ http://www.spacelaunchreport.com/unha.html
  7. ^ David Wright and Theodore A. Postol (2009-06-29). "A post-launch examination of the Unha-2". Bulletin of the Atomic Scientists. 
  8. ^ "More N. Korean Long-Range Rocket Launches Expected 'Soon'". Voice of America. July 31, 2013. Retrieved 2013-08-30. 
  9. ^ http://www.thebulletin.org/web-edition/features/post-launch-examination-of-the-unha-2
  10. ^ http://www.b14643.de/Spacerockets_1/Rest_World/Unha-X/Description/Frame.htm
  11. ^ "朝鲜将发射"光明星二号"试验通讯卫星" (in Chinese). Xinhua. 2009-02-24. Retrieved 2009-03-14. 
  12. ^ "North Korea fires long-range rocket: reports". The Sydney Morning Herald. 2009-04-05. Retrieved 2009-04-05. 
  13. ^ "Kim tours rocket launch area". The Straits Times. 2009-02-26. Retrieved 2009-03-14. 
  14. ^ "US Warns NK Not to Launch Rocket". The Korea Times. 2009-03-14. Retrieved 2009-03-14. 
  15. ^ "Russia urges North Korea to refrain from rocket launch". Asiaone News. 2009-03-27. Retrieved 2009-03-28. 
  16. ^ "Defiant N Korea launches rocket". BBC News. April 5, 2009. Retrieved May 24, 2010. 
  17. ^ "NORAD and USNORTHCOM monitor North Korean launch" U.S. Northern Command News. April 5, 2009. Last accessed April 5, 2009.
  18. ^ Sang-Hun, Choe; Cooper, Helene; Sanger, David E. (2009-04-06). "North Korea Seeks Political Gain From Rocket Launch". The New York Times. Retrieved 2009-04-07. 
  19. ^ Craig Covault (10 April 2009). "North Korean rocket flew further than earlier thought". Spaceflight Now. Retrieved 2009-04-17. 
  20. ^ "TEXT-N.Korea says it successfully launched satellite" Reuters UK 5 April 2009. Retrieved 30 June 2009.
  21. ^ "North Korea carries out controversial rocket launch". CNN. December 12, 2012. Retrieved December 12, 2011. 
  22. ^ "NORAD acknowledges missile launch". NORAD. 2012-12-12. Retrieved 2012-12-12. 
  23. ^ http://www.northcom.mil/News/2009/040509.html
  24. ^ http://www.space.com/15258-north-korea-rocket-launch-fails.html
  25. ^ "North Korea fires long-range rocket in defiant move, South Korea says". Fox News. 2012-12-11. Retrieved 2012-12-11. 
  26. ^ http://www.rfa.org/english/news/korea/delay-12102012141437.html
  27. ^ "North Korea announces rocket launch date". Al-Jazeera. 2012-12-01. Retrieved 2012-12-01. 
  28. ^ S. Korea military says N. Korea rocket launch a success

External links[edit]