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Images from the ground of the Unha-2 launch are starting to come in. Besides an amazing satellite image by DigitalGlobe and presented by GlobalSecurity.org of the the Unha-2 in flight, there are North Korean television images starting to appear in the West. (I should mention that the flare at the of the rocket’s contrail is not the rocket plume but rather indicates that the CCD camera on board the satellite saturated.) I’m going to be analyzing these images and hope to write more but I wanted to get these out as soon as possible.

There are a few comments I’d like to make:

1) The first stage is not quite as large as I thought based on a slanted satellite view. It’s much closer to half the rocket length than the 2/3 that I originally thought. I think I was mislead by the projection of the interstage as seen from a funny angle.

2) While you cannot see the individual nozzles on these images, you have to say its more consistent with a cluster of engines than a single engine. ( See this image of the missile in flight.)

3) The diameter is the first stage appears quite large. More work needs to be done on measuring it.

4) No fins are visible on these images or the one the of the missile in flight. While fins are not needed to insure a rocket’s stable powered flight, some analysts had automatically put them on their models.

5) No clear indication one way or another (at least with the cursory viewing of them I’ve made so far) of vernier engines or gimbaled engines.

Update: It’s a cluster! I cannot tell for sure whether or not its 2 or 4 engines but it is definitely a cluster. New info is coming so fast and furious that it’s almost worth missing the Carnegie conference.

By the way, so many of you are viewing this site, I am having a very hard time posting updates! This must be a good sign, but it’s causing me a lot of problems with lost work.

Update: The cluster of engines seems to use a single turbopump. Its still possible, of course, that each nozzle has its own turbopump but given the location of the exhaust exit, Im guessing that its a single pump. This implies a both a reduction in weight and an increase in sophistication on North Korea’s part. This image is a lot more convincing when you look at it in the video because you can see the exhaust plume from the turbopump pulsing.

Update: Gimbaled engines or jet vanes? I cannot tell for sure (if you look at the image of the turbopump exhaust I point to above) there appears to be four (you can see two spaced approximately 1/4 the way around the stage’s circumference) members sticking down from the airframe to below the nozzles. These could be either structural members to support the rocket on the launch pad or extensions for bringing down jet vanes to the level of the nozzle exits. I frankly think the support structures is a more likely alternative so I’m guessing the first stage is guided by gimbaled engines.

Update: I didn’t mean to rule out vernier engines. They are certainly still a possibility.

Update: The DigitalGlobe/GlobalSecurity.org image of the Unha-2 contrail is going to prove to be an analytical goldmine! I have made a rough GoogleEarth overlay of it it. Now, to find out the exact time the image was taken and use these to triangulate the Unha-2’s trajectory during early flight!