The third stage appears to be identical to the upper stage of the Iranian Safir-2 booster, which Iran used to put a small satellite into orbit in February 2009. The Safir-2 uses the small steering motors from the SS-N-6 for propulsion, Wright says.
“There is strong evidence that Pyongyang’s missile development program depended heavily on technology and assistance from Russian missile experts, although possibly without the involvement of the Russian government,” Wright wrote in a March 2009 analysis in the Bulletin of Atomic Scientists before launch of the Unha-2.
For that launch, North Korea for the first time announced splashdown zones for the first two stages and issued notices of the expected trajectory—something Pyongyang has also done for the Unha-3. It also invited the international press to view the booster, control room, and the 220-pound Kwangmyong-3 satellite designed to return data and images from orbit. The mission is part of the mid-April celebrations to make the 100th anniversary of the birth of North Korean founder Kim Il Sung.
“I think the bigger goal here is to reinforce the powers of the regime and to remind the world that they’re here,” says Brian Weeden, technical advisor at the Secure World Foundation and a former satellite tracking officer at U.S. Space Command. “We don’t expect them to invite in the international press for every launch.”
Unlike on previous orbital attempts, the North Korean state media reported—after a four-hour silence--that the Unha-3 did not reach orbit. Which may not matter to the North Korean people, who’ve been told their country already has two satellites in space.