North Korea claims that its impending satellite launch, scheduled for this week, is merely a mission to study the country’s “distribution of forests” and weather patterns. But after analysing the satellite’s potential flight paths, a network of amateur and professional spaceflight specialists have concluded that Pyongyang’s claim is all but impossible.
In order for the North Koreans to get a weather or observation satellite into the proper orbit, these experts say, Pyongyang would have to risk the early stages of its rockets dropping on its neighbours’ and allies’ heads.
“I believe that the most reasonable interpretation is that they are lying about this being a satellite launch, which has been betrayed by the incompetence of their propagandists in over-reaching in their cover story,” longtime satellite watcher Ted Molczan noted on the SeeSat listserv.
The Pyongyang regime has a long history of malarkey, of course. After its last satellite, the Kwangmyongsong-2 (Bright Star 2), plopped into the Pacific Ocean minutes after liftoff, North Korea swore that the thing was in orbit and transmitting “immortal revolutionary paeans” back to Earth. But this time, the debunking appears to be underway even before the rocket takes off from the Sohae Satellite Launching Station.
Shortly after announcing its latest launch, North Korea published the intended flight path of the rocket that would attempt to take the 1000kg Bright Star 3 satellite into space. As part of a standard warning to the region’s shipping and airline companies — known as a “notice to airmen” or “NOTAM” — Pyonyang said the booster rocket would fly due south, ejecting its first stage just west of South Korea and its second just east of the Philippines. “A safe flight orbit has been chosen so that carrier rocket debris to be generated during the flight would not have any impact on neighbouring countries,” the state-run KCNA news service promised on March 16. Airlines are now re-routing their flights based on that North Korean warning.
Pyongyang swore that the flight path would enable the satellite to assume what’s known as a “sun-synchronous” orbit — one that provides a constant angle between the sun, satellite and the ground below, giving the Bright Star-3 an almost consistent view of North Korea with every overflight. That’s the kind of orbit used by the overwhelming majority of low-earth-orbit imagery and weather satellites. And it would be consistent with North Korea’s promise that the Bright Star 3 was designed to examine its own crops and climate.
One small problem: The flight path published in North Korea’s “NOTAM” and its promised sun-synchronous orbit don’t match up, as Molczan, a veteran observer of spacecraft, discovered when he crunched the numbers. (This illustration best explains his analysis.)
“I do not see how North Korea could reach a sun-synchronous orbit from the new launch site without risk to populated areas,” he wrote on the SeeSat list. “Launching directly toward the required 192.3 [degree] azimuth would result in a trajectory that skirts China’s east coast near Shanghai. The rocket’s second stage would overfly Taiwan, before impacting in a zone bordering within perhaps 50km of the west coast of the northern Philippines.”
In other words, North Korea might be telling the truth about the direction of its launch, or the contents of it. But not both.
Yeah, there are some advanced techniques for readjusting to a sun-synchronous orbit, once the craft is in space. But North Korea isn’t terribly advanced. “I very much doubt that North Korea plans for its rocket stages to fall in the zones I have estimated,” he added, “but it is for North Korea to explain the inconsistency between the orbit it claims to be targeting and the NOTAMs it provided.”
The idea that a single satellite could survey both North Korea’s weather and its natural resources is pretty hard to believe, too. “It’s not common to have one satellite (a small one at that) doing all those missions,” former Air Force Space Command officer Brian Weeden emails Danger Room. “This is a country that has never successfully placed a satellite into orbit and doesn’t have a satellite industry. To try and put a fairly advanced satellite — remote sensing and weather, using UHF radio and X-band satellite communications — into a fairly precise orbit is quite the undertaking.”
NASA veteran Jim Oberg had a chance to see the Bright Star 3 up close, at the Sohae Satellite Launching Center. “I thought at first it was a model. I thought it was a symbolic representation. I couldn’t believe it was flight hardware. I couldn’t believe it was the one being launched in a few days,” he tells NBC news.
So it seems clear that Pyongyang isn’t trying to send a weather satellite into orbit. What is it planning on firing off into the skies? On that point, space-watchers are divided. Some, like Weeden, aren’t even sure it matters much.
“The main purpose is not to develop a real space program but rather ‘marketing’ the launch so as to limit the ways other countries can criticise the launch,” Weeden says. Iran started sending things into space in 2009. The international outcry was minimal, at best. Perhaps the North Koreans are “trying to replicate that in order to both continue testing and development of their missile technology and also increase the prestige and power of the regime. Whether or not they actually succeed in placing a satellite into orbit is likely a secondary goal.”
“For all we know,” he adds, “it could just be a bag of rocks on the tip of the booster.”
“The significance of the launch, of course, is the booster itself; the booster is bigger than it has to be,” Oberg concludes. “It’s not a military missile .. but it’s darn close…. This rocket is not a weapon, but it’s maybe 98 per cent of one.”
Image: AP/David Guttenfelder
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