South Korea has launched its first space rocket, though a scientific satellite it was carrying failed to enter into its proper orbit.

韩国发射第一颗宇宙火箭，搭载的一颗科技卫星没有进入预定轨道。

South Korean officials described the launch as a "partial success".

Millions of South Koreans watched the launch, but it is being viewed with suspicion by North Korea.

The North was recently subjected to UN sanctions for its own rocket launch, which was widely regarded as a cover for a long-range missile test.

There was no immediate¹ reaction from North Korea to Tuesday's launch.

South Korea's two-stage Naro rocket lifted off on Tuesday from an island off the south coast.

The satellite was placed into orbit but was not following its intended course, according to Science and Education Minster Ahn Byong-man.

"All aspects of the launch were normal, but the satellite exceeded its planned orbit," he was quoted as saying.

The satellite had reached an altitude（高度，海拔） of 360km (225 miles), rather than separating at the intended 302km, he said.

South Korean and Russian scientists were investigating the problem, he added.

Experts at the Korea Aerospace² Research Institute were cited by local media as saying they were trying to track the satellite.

A statement from the science ministry³ called the launch a "partial success", while South Korean President Lee Myung-bak called it a "half-success".

The rocket - 33m (108 ft) long and weighing some 140 tonnes - was the country's half-a-billion dollar bid to join the exclusive（独占的，唯一的） club of spacefaring nations.

Its Russian liquid-fuelled first-stage was said to have 1,700 kilonewtons of thrust at launch.

The second stage, burning a solid fuel, was produced by South Korean engineers.

Generating 80kN of thrust, it was intended to carry the Earth observation satellite into its final orbit.

South Korea initially⁴ planned to launch the rocket in late July, but delayed it several times due to technical problems.

South Korea has previously⁵ sent satellites into space using launch vehicles and rockets from other countries.

Seoul has rejected any comparison with Pyongyang's rocket launch and says its rocket is part of a peaceful civilian⁶ space programme.

But some security analysts⁷ have suggested a commercial space programme could still alter the long-term strategic balance in the region, as all rocket technology has potential military uses.

No North Korean satellite has been detected in space, although Pyongyang insists its rocket launch worked and the device is now orbiting the earth transmitting revolutionary melodies.