Korea becomes world's sixth sat power

(Korea Times via NewsEdge) On July 28, a group of South Korean scientists nervously huddled around a TV monitor at the Korea Aerospace Research Institute (KARI) in Taejon, about 200 kilometers south of Seoul.


As the rocket on the screen blasted off and disappeared into the sky, they erupted into a loud cheer full of a sense of victory. Unfortunately, their boss wasn't with them. He was in Russia, checking the launch in person.


That was the moment Korea became the world's No. 6 satellite power, joining the ranks of a handful of nations with the capability of taking satellite pictures with a 1-meter resolution.


Arirang-2 took off from the Plesetsk Cosmodrome, approximately 800 kilometers northeast of Moscow, just after 4 p.m. (Korean time) and settled into its orbit 685 kilometers above the earth.


"At that time, I felt as if I were on fire because a couple of days before the liftoff a similar rocket had exploded when carrying a satellite," said KARI director Lee Joo-jin, who is in charge of the Arirang-2 project.


"However, the rocket loaded with Arirang-2 did its job without any glitch and we could finally forget all the stress built up over years of hard work," Lee, who watched the launch at the site, added.


Two days before Arirang-2 took to the sky, a Russian booster, a Dnepr rocket converted from an intercontinental ballistic missile, exploded when carrying another Korean satellite, the Hausat-1.


Hausat-1 was a small box-sized satellite produced with a minimal budget by researchers at Hankuk Aviation University to help students better understand the process of manufacturing satellites.


Lee had reason to worry. Like the Dnepr rocket, the rocket carrying the Arirang-2 was also transformed from an intercontinental missile.


To the relief of Lee and his associates, the Rockot launcher soared into the sky without problems and Arirang-2 successfully separated from the three-stage booster and deployed its solar panels, which allowed the earth-probing satellite to use solar power.


The ground control station checked that the 800-kilogram Arirang-2 was in its designated orbit and was functioning properly.


It would begin taking high-resolution pictures starting September.


Tasks ahead


Although the nail-biting moment is over, Lee is still busy working on more missions: more work on Arirang-2 and other satellites that will travel to space in the years to come.


First, Lee is required to complete the No. 1 mission of Arirang-2 - to provide as many high-resolution pictures as possible with its embedded multi-spectral camera (MSC), a high-end camera that can take two or more images of a scene simultaneously, with each image taken in a different spectral band.


"So far, Arirang-2 is good. We are sure that it will be able to take pictures beginning next month. We're fine-tuning the process right now," Lee said.


Korea launched its first multi-purpose satellite, Arirang-1, in December 1999 from Vandenberg Air Force Base in California, on an Orbital Sciences-made Taurus rocket.


Although equipped with an airborne camera, the quality of images taken by the Arirang-1 was poor, as it identified an object 6.6 meters in diameter as a mere dot.


By comparison, Arirang-2 was armed with a 1-meter resolution camera, made jointly with Israel-based company Elop.


"The new 1-meter MSC of Arirang-2 can identify whether a moving vehicle is a truck or a passenger car at the altitude of 685 kilometers above the ground," Lee said. "Only a few nations such as the United States, Japan, Israel and France have these cutting-edge devices. It is still not known whether Russia and China have them."


Lee said that, in a sense, Korea became the world's sixth-strongest satellite power in airborne camera technologies with the liftoff of Arirang-2 and its MSC, which cost KARI 263.2 billion won ($276 million).


Arirang family


Lee flatly denied that the satellite had any military uses.


Local media reported that Arirang-2 could provide improved reconnaissance, especially about North Korea. Some even argued that Arirang-2 was designed to drop to lower altitudes for better satellite photos in an emergency.



A source familiar with Arirang-2 also said the MSC on Arirang-2 had multiple functions, including airborne surveillance.


"If North Korea launches a missile at an open-air site, Arirang-2 will be able to take pictures and transfer them to the ground virtually on real-time basis," the source said. "With Arirang-1, we could not identify even trucks shipping missiles due to the low-definition of photos. But the Arirang-2-incorporated MSC has about 45 times better resolution than its predecessor."


Despite such claims, Lee reiterated that the Arirang-2 was for non-military purposes.


"From the very beginning, Arirang-2 was designed as a remote-sensing device for geographical surveys, natural resource searches and environmental observation," he said. "It is also an erroneous idea that Arirang-2 can descend to a lower altitude in an emergency. Its fuel is not enough to enable it to drop to a lower altitude even once."


KARI will launch other advanced satellites, Arirang-5 and Arirang-3, in 2008 and 2009, respectively. Lee is in charge of all the Arirang family satellites.


The Arirang-5 attracted attention because it was outfitted with a synthetic aperture radar (SAR) system, which took advantage of the unique characteristics of radar signals, capturing above-the-ground imageries with minimum constraints of time-of-day and atmospheric conditions.


"Ever since Arirang-1 was launched in 1999, it has been one of the top priorities of the nation's space projects to get good satellite coverage," Lee said. "Arirang-2 has markedly upgraded abilities, but its camera is of little use in inclement weather or at night. But the SAR is different as it can work even in terrible air conditions."


Another plus of the SAR is that it can capture underground or undersea information for mineral exploration.


© 2006 Korea Times.