By Pam Benson
While the Obama administration is urging North Korea not to go ahead with its expected rocket launch, the launch does present one benefit: The U.S. intelligence community will get the rare opportunity to more precisely see just how far North Korea has progressed with its long-range missile technology program since its last launch three years ago.
Although North Korea says it is merely deploying an Earth observation satellite, something it has failed at doing in the past, the United States believes the secretive nation is really testing technology that would also enable it to fire a ballistic missile carrying a warhead, one that could potentially strike the United States.
But the real question is whether the rocket performs as intended, especially that third stage, which releases the satellite.
The United States, Japan and other regional powers have the area around the Korean peninsula blanketed with all kinds of tracking and surveillance equipment to zero in on every moment of the flight, from launch to satellite deployment to the debris that falls into the ocean.
A U.S. official told Security Clearance there will be aerial assets in the region - specially equipped Air Force planes - to complement early warning satellite imagery, as well as Aegis ships with high power radar systems. The giant XBand radar, which sits on an oil rig sized floating platform and is used in conjunction with missile defense, has been deployed to the region from its base in Hawaii. Military and intelligence officials and experts will monitor the launch from locations around the world, including the Pentagon and U.S. Pacific Command in Hawaii.
In case something should go awry and the missile veers off path or the payload appears to be something other than a satellite, the Aegis ships in the region and U.S. land-based interceptors are on alert to try to shoot down the North Korean rocket if necessary. Japan also has its Patriot missiles on standby to take defensive measures.
North Korea has said the rocket will travel on a north to south path with splash zones for the first two stages in the East China Sea and the Pacific Ocean.
If there is any doubt whether this is a satellite launch or an intercontinental ballistic missile test, the path the rocket takes should provide the answer quickly.
David Wright, a physicist with the Union of Concerned Scientists, said a satellite launch "starts out more steeply, it then turns over and goes horizontal to put the satellite in orbit, where as an ICBM trajectory would continue essentially rising." Wright has posted on his website a chart showing the two paths.
Another indication of how well the flight is progressing is whether each stage hits the splash zones projected by North Korean officials. In the 2009 launch, the first two stages appeared to perform as planned, although the stages landed at the front of the zone, leading experts to conclude there was not as much thrust as anticipated.
But it is the third stage that is far more complicated and where the North Koreans have previously failed.
"The earlier stages fell early and the last stage in previous tests basically blew up or fell apart or didn't make it to get the satellite into orbit," said Mike Green, a former senior Asia adviser in the Bush administration. Green added the key is to get each stage to detach itself so the rest keeps flying in a straight line.
Wright said it isn't easy. "There are various ways the third stage can be more problematic," Wright said. "Once it ignites it has to burn for a very long time, five minutes or so, and during that time it has to keep itself from tumbling, it has to keep itself on the right trajectory. So one question is whether they (the North Koreans) can really control it well."
All this happens in a relatively short period. Wright estimated the timetable of the launch to satellite deployment should be approximately 110-120 seconds for the first stage, the same time frame for the second stage and 300 seconds for the final stage. The satellite would be released into orbit at the end of the third stage burnout. So, all told, the launch from the pad to release of the satellite should be approximately nine-10 minutes.
The intelligence community already has a pretty good idea what to expect from the launch, having watched from its eyes in the sky the assembling of the three rocket stages on the launchpad at Tongchang-ri.
Retired Maj. Gen. Spider Marks, a CNN contributor, said U.S. intelligence agency satellites are capable of zooming in with "a high level of granularity" to see the components of the rocket.
"They have now run all of the models, which give a very detailed view of what its performance characteristics are going to be," the former intelligence officer said.
One change already observable from its position on the launchpad is the third stage of this rocket is slightly longer than the nearly identical one launched in 2009.
David Wright attributed the difference to North Korea's decision to launch this rocket on a north to south path instead of the previous west to east direction.
"In 2009, they were launching east over Japan, and when you launch a satellite in that direction, the rotation of Earth actually helps you," Wright said. "it gives you some extra speed. This time they are flying south to avoid going over Japan so they lose that extra speed from the Earth. To make up for that they would have to add fuel to the third stage. If you add fuel to the third stage it adds mass to the rocket."
If the satellite launch is successful, experts believe North Korea will be well down the road to firing an ICBM. Although Wright referred to the payload as a toy satellite, something without much capability, he said, "If it works, what it means is that they have been able to get the technology of these three stages to work correctly ... knowing how that technology works can allow them to use that technology for a ballistic missile, to launch on a different trajectory and with a different warhead."
Green added, "It's all part of a ladder they are climbing up."
But it may not end there. The next challenge for the intelligence community could be right around the corner with a possible underground nuclear test by the North Koreans. A South Korean intelligence report obtained by CNN includes recent satellite imagery showing increased activity at the site where North Korea has conducted two previous nuclear tests. In both 2006 and 2009, a rocket launch was followed by a nuclear test.
Marks finds the combination of events disturbing. "Even if the exact events are not linked in terms of desired outcome, they're coincidence on the calendar, next to each other, conducting one and then the next in close sequence is the thing that is really troubling," Marks said. "It just demonstrates to you both programs are continuing in parallel."