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Unha

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Unha
Unha-3 at launch pad in April 2012
FunctionExpendable carrier rocket
ManufacturerNational Aerospace Development Administration
Country of originNorth Korea
Size
Height28–30 metres (92–98 ft)[1]
Diameter2.4 metres (7 ft 10 in)
Mass86,750–91,000 kilograms (191,250–200,620 lb)
Stages3
Capacity
Payload to LEO
Mass200 kg (440 lb)[2] (465 x 502 km)
Launch history
StatusActive
Launch sitesSohae, Tonghae
Total launches4
Success(es)2
Failure(s)2
First flight5 April 2009[3]
First stage
Height15 m (49 ft)
Diameter2.4 m (7 ft 10 in)
Powered by4 Nodong 2-1[4][1]
Maximum thrust1192.8 kN[4][1]
Specific impulse252 sec[5][1]
Burn time120 seconds[5][1]
PropellantN2O4/UDMH[4][1]
Second stage
Height8.8–9.3 m (29–31 ft)
Diameter1.5 m (4 ft 11 in)
Powered by4 verniers[4]
Maximum thrust125 kN[1]
Specific impulse255 s[5]
Burn time220 seconds[5][1]
PropellantN2O4/UDMH[4][1]
Third stage
Height3.7–5.7 m (12–19 ft)
Diameter1.2–1.25 m (3 ft 11 in – 4 ft 1 in)
Powered by2 verniers[4][1]
Maximum thrust35.4 kN[1]
Specific impulse230 sec[5]
Burn time245 seconds[5]
PropellantN2O4/UDMH[4]

The Unha or Eunha (Korean: 은하, 銀河, "Galaxy")[6] is a North Korean expendable carrier rocket, which partially utilizes the same delivery system as the Taepodong-2 orbital launch system.[7]

History

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North Korea's first orbital space launch attempt occurred on August 31, 1998, and was unsuccessful. This launch attempt was performed by a Paektusan-1 rocket, which used a solid motor third stage, a Scud-missile-based second stage, and a Nodong-1 based first stage. Nodong-1 was a North Korean-developed stage thought to be a scale-up of the old Soviet Scud missile. The Paektusan-1 stood 22.5 metres (74 ft) tall, was 1.8 metres (6 ft) in diameter, and weighed about 21 tonnes.[citation needed]

Vehicle description

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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, too, is now believed to be based on Scud technology.[4] The third and last stage might be identical to the Iranian Safir's second stage which is propelled by two small gimballed motors.[4][8]

Recent satellite images of the Sohae Satellite Launching Station showing an enlarged launch tower under construction have prompted online speculation that an enlarged version, called "Unha-X", might be under development.[9]

Unha
Chosŏn'gŭl
은하
Hancha
Revised RomanizationEunha
McCune–ReischauerŬnha

Launch history

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On 24 February 2009, North Korea announced that a Unha rocket would be used to launch the Kwangmyŏngsŏng-2 satellite.[10] According to the South Korean government, the launch took place on 5 April[11] from the Tonghae Satellite Launching Ground in Hwadae county.[12] Several countries, including South Korea, the U.S., and Japan, voiced concerns that the launch would violate United Nations Security Council Resolution 1718 which prohibits North Korea from testing ballistic missiles.[13] Russia also announced they urged North Korea to refrain from its planned rocket launch.[14]

On April 5, 2009, the Unha-2 rocket was launched at around 02:30 hours UTC (11:30 hours KST).[15] 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.[16][17] 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.[18] North Korea maintains that the rocket successfully put its payload in orbit.[19]

On December 12, 2012, the Unha-3 Unit-2 rocket was launched at 00:49 UTC (7:49 EST).[20] 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 the satellite had entered orbit.[21]

Designation Date Launch Site Payload Outcome
Unha-2 5 April 2009 Tonghae North Korea Kwangmyŏngsŏng-2 Failure
Unha-3 13 April 2012 Sohae North Korea Kwangmyŏngsŏng-3 Failure[22]
Unha-3 12 December 2012[23][24] Sohae North Korea Second version of Kwangmyŏngsŏng-3[25] Success
Kwangmyŏngsŏng (Unha-3) 7 February 2016 Sohae North Korea Kwangmyŏngsŏng-4 Success

See also

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References

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  1. ^ a b c d e f g h i j k Brugge, Norbert. "Unha-3". Space Rockets Rest Of World. Retrieved 30 December 2017.
  2. ^ "Status of North Korean Satellite unknown after prolonged Radio Silence, Reports of Tumbling – Spaceflight101". 12 February 2016. Archived from the original on 12 November 2019. Retrieved 30 December 2017.
  3. ^ Krebs, Gunter. "Unha ("Taepodong-2")". Gunter's Space Page. Retrieved 19 April 2012.
  4. ^ a b c d e f g h i David Wright (22 February 2013). "Markus Schiller's Analysis of North Korea's Unha-3 Launcher". All Things Nuclear. Union of Concerned Scientists. Archived from the original on 6 March 2013. Retrieved 7 March 2013.
  5. ^ 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. Archived from the original (PDF) on September 3, 2014. Retrieved January 23, 2013.
  6. ^ Kim, Jack (2009-03-13). "FACTBOX: North Korea's Taepodong-2 long-range missile". Reuters. Retrieved 2009-03-30.
  7. ^ "North Korea positions rocket for April liftoff". AP. 2009-03-27. Archived from the original on 2009-03-29. Retrieved 2009-03-28.
  8. ^ "A post-launch examination of the Unha-2". 29 June 2009. Archived from the original on 23 March 2012. Retrieved 4 April 2012.
  9. ^ "Unha-X".
  10. ^ 朝鲜将发射"光明星二号"试验通讯卫星 (in Chinese). Xinhua. 2009-02-24. Archived from the original on February 27, 2009. Retrieved 2009-03-14.
  11. ^ "North Korea fires long-range rocket: reports". The Sydney Morning Herald. 2009-04-05. Retrieved 2009-04-05.
  12. ^ "Kim tours rocket launch area". The Straits Times. 2009-02-26. Retrieved 2009-03-14.
  13. ^ "US Warns NK Not to Launch Rocket". The Korea Times. 2009-03-14. Retrieved 2009-03-14.
  14. ^ "Russia urges North Korea to refrain from rocket launch". Asiaone News. 2009-03-27. Archived from the original on March 31, 2009. Retrieved 2009-03-28.
  15. ^ "Defiant N Korea launches rocket". BBC News. April 5, 2009. Retrieved May 24, 2010.
  16. ^ "NORAD and USNORTHCOM monitor North Korean launch" Archived 2012-10-17 at the Wayback Machine U.S. Northern Command News. April 5, 2009. Last accessed April 5, 2009.
  17. ^ 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.
  18. ^ Craig Covault (10 April 2009). "North Korean rocket flew further than earlier thought". Spaceflight Now. Retrieved 2009-04-17.
  19. ^ "TEXT-N.Korea says it successfully launched satellite" Reuters UK 5 April 2009. Retrieved 30 June 2009.
  20. ^ "North Korea carries out controversial rocket launch". CNN. December 12, 2012. Retrieved December 12, 2011.
  21. ^ "North Korea Successfully Launches Satellite: Reports", SPACE.com, December 12, 2012 (accessed 24 Sept. 2014)
  22. ^ "North Korea Long-Range Rocket Launch Fails: Reports". Space.com. 13 April 2012.
  23. ^ "North Korea fires long-range rocket in defiant move, South Korea says". Fox News. 2012-12-11. Retrieved 2012-12-11.
  24. ^ "North Korea Delays Rocket Launch".
  25. ^ "North Korea announces rocket launch date". Al-Jazeera. 2012-12-01. Retrieved 2012-12-01.
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