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]

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]

History

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

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

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]

DesignationDateLaunch SitePayloadOutcome
Unha-25 April 2009Tonghae Kwangmyŏngsŏng-2Failure
Unha-313 April 2012Sohae Kwangmyŏngsŏng-3Failure[22]
Unha-312 December 2012[23][24]Sohae Second version of Kwangmyŏngsŏng-3[25]Success
Kwangmyŏngsŏng (Unha-3)7 February 2016Sohae Kwangmyŏngsŏng-4Success

See also

References

External links