Unha

This article is about the North Korean rocket. For the given name, see Eun-ha. For other uses, see Unha (disambiguation).

The Unha^[a] (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
Function	Expendable carrier rocket
Manufacturer	National Aerospace Development Administration
Country of origin	North Korea
Size
Height	28–30 metres (92–98 ft)[1]
Diameter	2.4 metres (7 ft 10 in)
Mass	86,750–91,000 kilograms (191,250–200,620 lb)
Stages	3
Capacity
Payload to LEO
Mass	200 kg (440 lb)[2] (465 x 502 km)
Launch history
Status	Active
Launch sites	Sohae, Tonghae
Total launches	4
Success(es)	2
Failure(s)	2
First flight	5 April 2009[3]
First stage
Height	15 m (49 ft)
Diameter	2.4 m (7 ft 10 in)
Powered by	4 Nodong 2-1[4][1]
Maximum thrust	1192.8 kN[4][1]
Specific impulse	252 sec[5][1]
Burn time	120 seconds[5][1]
Propellant	N2O4/UDMH[4][1]
Second stage
Height	8.8–9.3 m (29–31 ft)
Diameter	1.5 m (4 ft 11 in)
Powered by	4 verniers[4]
Maximum thrust	125 kN[1]
Specific impulse	255 s[5]
Burn time	220 seconds[5][1]
Propellant	N2O4/UDMH[4][1]
Third stage
Height	3.7–5.7 m (12–19 ft)
Diameter	1.2–1.25 m (3 ft 11 in – 4 ft 1 in)
Powered by	2 verniers[4][1]
Maximum thrust	35.4 kN[1]
Specific impulse	230 sec[5]
Burn time	245 seconds[5]
Propellant	N2O4/UDMH[4]

History

North Korea's first orbital space launch attempt occurred on 31 August 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 Hwasong-7 (Nodong-1) based first stage. Hwasong-7 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	銀河
Revised Romanization	Eunha
McCune–Reischauer	Ŭnha

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 5 April 2009, the Unha-2 rocket was launched at around 02:30 a.m. UTC (11:30 a.m. local time).^[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]

An Unha-3 rocket was launched at 00:49 a.m. UTC, 12 December 2012.^[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	Kwangmyŏngsŏng-2	Failure
Unha-3	13 April 2012	Sohae	Kwangmyŏngsŏng-3	Failure[22]
Unha-3	12 December 2012[23][24]	Sohae	Kwangmyŏngsŏng-3 Unit 2[25]	Success
Kwangmyŏngsŏng (Unha-3)	7 February 2016	Sohae	Kwangmyŏngsŏng-4	Success

See also

• Comparison of orbital launchers families
• Timeline of first orbital launches by country
• Naro-1
• Simorgh
• Chollima-1

Notes

1. Also romanized from Korean script as Eunha under South Korea's Revised Romanization.