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Subscribe to RSSAfter Tuesday's nuclear test, questions arose as to whether or not North Korea has advanced to the point where they could reach the continental U.S. with a missile.
This week's North Korean nuclear test raises the crucial question of how close Pyongyang is to "weaponizing" its nuclear devices and rockets. It's difficult to tell, due to the country’s trademark secretiveness, but the progress to date suggests that North Korea is committed to a long-term, trial-and-error campaign to put all the pieces together.
The country's two rocket launches over the past year serve as an apt illustration: Last April, an NBC News team spent 10 days in North Korea to observe the preparations and launching of a "peaceful" Earth-observing satellite. The trip turned into a P.R. debacle for the North Koreans. They held back the key evidence that could have demonstrated peaceful intent, and their rocket failed after a covert blastoff.
In December, North Korea finally launched a satellite into orbit, but again failed the "openness" test by concealing what the rest of the world soon found out anyway: that the satellite was dead on arrival, a drifting derelict.
So what's next? If North Korea’s secret plan is to develop a system capable of menacing the United States, an intercontinental launch and re-entry system is the key part of the puzzle. Last year, U.S. intelligence sources told NBC News that North Korea already may have up to a "few dozen" nuclear weapons that could be fitted on ballistic missiles.
Based on historical precedents from the original U.S.-Soviet missile race, more than half a century ago, two technological challenges stand out:
- Providing a heat shield for a re-entry vehicle carrying a nuclear warhead: One option would be to use an "ablative" shield that absorbs the tremendous heat of atmospheric re-entry by burning away layers of material. For all we know, testing of such materials has already started.
- Fabricating components rugged enough to weather the stresses of a rocket ascent: It's conceivable that the satellite failure in December was due to inadequate robustness of the satellite's systems.
Too rough of a ride?
One of the lessons from April's visit was that the North Koreans prided themselves on working things out for themselves. They seemed almost to boast about how they didn't need to learn from any other country's experiences. After April's failure, North Korean statements reflected a more cautious approach to the challenges. News reports told how the rocket team had vowed to increase the quality and care of their own work. The Koreans accepted responsibility for the failure, rather than blaming foreign enemies for sabotage.
December's launch attempt marked a success for the rocket, but an apparent failure for the satellite. Post-launch reports from U.S. intelligence sources as well as the global satellite-watching community confirmed that the spacecraft never emitted a single beep. To this day, it continues to tumble end over end in orbit.
Such a failure would have a direct bearing on the construction of a reliable nuclear warhead for a long-range missile, since an intercontinental nuclear strike would use the same type of rocket that launched the satellite. True, a warhead and a satellite are different devices — but they would share critical control components, including electronics as well as rocket thrusters.
The plans announced by North Korea call for launching two more Earth-observing satellites — which would provide at least two more opportunities to test the ruggedness of onboard systems.
How to test a heat shield
Meanwhile, the North Koreans would also need to test the heat shielding for re-entry vehicle, either for purportedly peaceful purposes or for nuclear warheads. Ground laboratories can simulate some of the heat flow, but flight tests with actual deceleration stresses are also required.
Historically, even Nazi Germany's short-range V-2 missiles experienced enough heating to detonate their explosives. This required adding layers of plywood as makeshift heat shielding.
By the time long-range missiles appeared in the mid-1950s, rocket designers had run into a "wall" of severe heating. It took years for the Soviets and the Americans to develop adequate heat shields and the means for testing them. For the United States, the creation of the Jupiter-C rocket, later upgraded and renamed the Juno-1, marked the key advance. That rocket successfully pushed a test warhead back into the atmosphere at speeds equivalent to long-range flights — and soon afterward, it launched the first U.S. satellite, Explorer 1.
This underscores a contemporary issue: A rocket built to test warhead heat shields would be virtually identical to a rocket for launching small satellites, because the desired speeds are similar.
North Korea could conduct such test flights at any time, either as overt missile tests, or disguised as a satellite mission. Theoretically, the rocket wouldn’t even have to fly very far across Earth's surface to its full range. It could pop up into space and then, with its upper stages still firing, turn back down into the atmosphere to attain the speeds equivalent to a full-range firing.
KCNA / NBC News
December's launch of North Korea's Unha-3 rocket is displayed on an array of screens at the country's satellite control center.
In that profile, outside observers would see a shorter-range flight. It might be harder to determine what was actually being tested. Seeing recovery ships in an impact zone — say, 600 miles (1,000 kilometers) off the North Korean coast — might be one clue. The test payload need only relay a brief radio burst confirming its survival before splashing into the ocean and sinking out of sight.
Such a payload could piggyback on a satellite launch — which raises the possibility that the North Koreans could have conducted heat-shield tests during last year’s launches. Despite repeated promises, our hosts never showed us what was under the rocket's aero shroud last April. So there was no way to rule out the possibility of a hidden test.
Although the North Koreans have the home-field advantage, by virtue of their status as the most closed society on the planet, the outsiders who are trying to figure them out have a greater advantage: The reality of rocket science is the ultimate judge, rewarding and punishing the same traits in all space programs. Where Pyongyang leaves blanks and shadows, experienced rocketeers can often fill in the gaps with reasonable implications and deductions from other national projects.
That's why our April "road trip" to North Korea was a success for those trying to understand North Korea’s rocket program — and a failure for those trying to distort it.
More about North Korea's nuclear intentions:
- China speaks softly during Korea crisis
- What North Korea's rocket ruckus taught us
- Video: North Korea confirms nuclear test
- More about North Korea on NBCNews.com
NBC News space analyst James Oberg spent 22 years at NASA's Johnson Space Center as a Mission Control operator and an orbital designer. He was part of the NBC team that visited North Korea last April.
Leave a Comment:
What...they're going to attempt to launch a missile and it explodes at about 1000 feet? Perfect! I love history.
North Korea and the world tolerance for its existence is going to be a significant blot on the history of humanity. Especially for China and it's near total responsibility for allowing it to continue.
The UN will continue to be less than an ineffective voice against it. By giving the appearance of a legitimate international legal organization "handling" NK, it makes sure that there is no chance that anything will actually be done to end the horror and growing infection that is NK.
If history is to be consulted for the future of NK, it will likely invade SK to prevent its own internal collapse and its own people from ending their wretched degrading existence of squalor and torment. China will probably use such an event as an opportunity to conduct a "humanitarian" police action and sweep into all of the Korean peninsula. The flood of refugees will be corralled and many of the women will be swept into the existing trafficking of Korean women to China's rural regions where the one-child doctrine has resulted in massive gender imbalance and millions of men with no women to marry and have families.
North Korea will wave their sword at the US and the UN. The US will go into "negotiations" (ala Bill Clinton) and end up giving N. Korea money and maybe some more nuclear material to "help them" not move towards nuclear weapons. North Korea will continue to starve and exploit their people while building nuclear weapons, feeding and serving their military, and selling illegal weapons to rogue nations. They will likely also aid other rogue nations towards their getting weapons of mass distruction.
History has also shown that North Korea can do this crap for a long time........
What's next for North Korea's nuclear missile program?
Trying to find someone who's not to weak from hunger to crawl to the bunker and hit the launch button.
Successful launch of long range rocket--- check
Successful testing of improved nuclear bomb--check
Hmmm what do these facts have in common ?
Ummm, they were both successful?
There are several interesting points that the article didn't mention and a couple of implications that are patently false:
1) The North Korean Unha rocket was a three-stage rocket. The bottom two stages were liquid-propelled and the top stage presumably so, though it could be solid-fueled. Liquid-fueled rockets are really not suitable for military purposes except as a last resort. The problem is that it takes several days to several weeks to set up and launch. If international tensions were such that we had even a tiny inkling that they were preparing a launch with a nuclear warhead, we would instantly launch a couple of Tomahawks and make the missile disappear. Unless a liquid-fueled rocket is mobile and single-stage, it is worthless for military purposes.
2) The North Koreans are third in the world as sellers of military rockets, mostly home-grown SCUD variants with improved range, guidance, and warhead weight. They have launched any number of them and could have tested the re-entry shielding on any one of them. One would presume that that would have happened very early in the development process, not this late.
3) NK launches have been over Japan to the east. Because of Japanese complaints, the last two have been fired to the SSW over open ocean. But this posed a huge problem since the satellite was to be in a sun-synchronized polar orbit. This meant that in the successful launch, the third stage had to excute a tricky S-turn to reposition itself pointing east before it fired. This was a huge accomplishment with major significance in developing an ICBM.
4) Before marking the NK satellite as a "failure" we need to wait a bit. The statement that the satellite is "tumbling out of control" still has a chance of being erroneous. Amateur astronomers have monitored the rate of tumble by timing flashes of light off the satellite. The rate of tumbling was never all that bad and has been slowing. There are electro-mechanical devices that can be used to stabilize the satellite that can take weeks to work. There is still a possibility that such a device is in use. Here is a NASA paper on such devices: http://ntrs.nasa.gov/search.jsp?R=19700058029
5) North Korea has been actively working with Iran in boith the nuclear weapons area and in rocketry. Iran has been a key supplier of more modern guidance systems, structural materials, and especially solid fuel for rockets. What we need to be watching for is a NK launch of a sloid fueled single-stage rocket with more than 1,000km range. That bad boy would be an ideal nuclear missile since it covers almost the entire Korean theater of operations, including Japan.
6) One point about the nuclear test. The fact that it was a presumed smallish detonation has little bearing on the size of the weapon being tested. This is because "modern" nukes are two-stage devices with the first stage acting as a trigger to detonate the second stage. One does not need to test both stages together. You only have to explode the first stage and measure the particles/radiation that is fed into a dummy second stage to see if it is successful. This especially makes sense when you have a slow steady production of plutonium and need to conserve fissile material to build your arsenal.
Just saying ....
"The North Korean Unha rocket was a three-stage rocket. The bottom two stages were liquid-propelled and the top stage presumably so, though it could be solid-fueled. Liquid-fueled rockets are really not suitable for military purposes except as a last resort. The problem is that it takes several days to several weeks to set up and launch. If international tensions were such that we had even a tiny inkling that they were preparing a launch with a nuclear warhead, we would instantly launch a couple of Tomahawks and make the missile disappear. Unless a liquid-fueled rocket is mobile and single-stage, it is worthless for military purposes."
Learn more.
Many modern ICBMs are liquid fuelled. And some of the Russian liquid-fuelled missiles are stored FUELLED, and have very fast reaction times. Sorry you didn't know that.
If weaponized, the Unha-3-class missile wouldn't be sitting out on a football-sized concrete apron. It could easily be based inside alleys between apartment buildings in any major NorKor city. At Sohae we saw that ALL logistic support to the launch pad was by wheeled transport, making deployment ANYWHERE near roads -- with a tall enough structure to allow stacking -- easily accomplished.
Thanks for your technical comments, they were pretty good otherwise.
Sounds like it's time for some good old fashioned sabotage... rig the very first one Un dubs "Little Dong" in honor of himself to blow right on the ground while paraded past the palace and call it poetic justice.
One of the reasons (though not the main reason) that North Korea conducts these periodic provocations, such as the sinking of the Chongnan is so that they can monitor the chain of commnand all the way to the point of execution. When the order is given, political officers watch every individual not for sabotage, nor for shows of disloyalty, but even things like slight hesitation or not being properly prepared. When the political officer points his finger at someone, that person and his family, usually including his parents, are sent to a death camp. In the past 60 or so years, pretty much all dissenting voices have been stilled.
NK is much like the world of "1984" in that the vast majority of the people sincerely believe the propaganda. Obviously they donot literally believe the mataphors, but they do literally believe that the military threat from the US/Japan/South Korea is real and about to happen. And they believe that a "military first" society and economy is the only reasonable way to stand up to these evil threats.
The obvious understated: bomb South Korea. Duh.
FYI: The Korean war is one of many the US didn't win. So history is on the North's side. (You can bet on this outcome, if you are the wagering type.) Remember WWII? The USA in bed with the Russians. In the next Korean war it will be the Chinese under the sheets with US. Based on D.C.'s lousy foreign policy history another cold war will follow, only this time they own US.
Without change, history must repeat itself. Even average citizens could run a better federal government. ©2013
Why are they even wasting their time. They are so far behind us, if they actually built something that could fly and deliver a nuke, we could nuke them with our tv remotes.
A heat shield is only needed if you want to strike a target at or close to ground level. A nuke in orbit could cause an EMP that would devastate a much larger area and would be far more damaging in the long term than any single ground target. The assumption of North Korea's lack of heat shield technology is not the barrier to having a useful weapon that the author is saying it is.
The EMP threat is vastly overstated and is more sci-fi than an actual military threat. It would have little to no effect on the military since their gear is milspec EMP-hardened. You can find neat maps on the internet that show that the Starfish Prime test knocked out some streetlights in Hawaii, 900 miles away. But the damage was so minimal that little attention was paid to HEMP (its proper name) except in movies.
You can find neat maps that map the Starfish Prime data over the USA and include "new" data on the Earth's electromagnetic field. It shows than a single HEMP pulse from a 1.4 mt weapon at the proper altitude could cause damage in much of the USA. In fact, this extrapolation presumes a number of really bad assumptions. The primary assumption is that there is zero atmospheric moisture and zero cloud cover. How many days can you remember when there were no clouds and a humidity of zero? The answer is zero. If you factor in normal weather patterns and humidity and things like fog then the HEMP weapon pretty much fails as badly as most laser projects. HEMP is not something that we need to worry much about.
What is China's real long term goal for allowing North Korea to become such an extreme totalitarian nation of misfits? Basically a nation of soldiers, homogeneous and zombie-like, that will obey any order from their God-like leader.
Why is China equipping North Korea with nuclear weapons and launch capabilities?
Why does China need an aircraft carrier?
Why is China planting thousands of cells in all foreign countries, especially in the US.
Why is China arming the El Qaeda terrorists with weapons and RPGs?
1) China is NOT equipping North Korea with nuclear weapons and launch capabilities. These are entirely home-grown efforts. China ceased all military aid and support of North Korea years ago when the Clinton initiative failed.
2) China "needs" an aircraft carrier for exactly the same reasons that the USA "needs" eleven of them.
3) China is undoubtedly planting "cells" in the US and the US is doing the same in China. If the Cold War success of these operations between the USA and USSR can be used to estimate success, the USA is planting about eight successful "cells" to one Chinese cell and is turning about half of the Chinese cells. That's just the way the game is played.
4) China is not arming al-Quaeda with weapons and RPGs. In fact, China is fighting al-Quaeda insurgency amng the Uyghur, Hui and Tajik ethnic groups. Chinese-made weapons, like North Korean-made and Soviet-made weapons are heavily used by virtually all insurgencies because they are plentiful, cheap, rugged, and easily available in international arms market several dealers removed from China itself.
Does that help? If not, have you tried tinfoil?
I wonder if the American scientists who released the nuclear genie from its bottle with hostile intent ever considered the fact that it can never be forced back in that bottle and that the third city destroyed by this evil genie might very well be an American city. Even in the expediency of war, actions have consequences for the future.
The only reason America released that genie first is that Germany found it too expensive to persue. It was just a matter of time till someone would have.