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The amazing satellite image by DigitalGlobe and presented by GlobalSecurity.org of the Unha-2 in flight can be used to determine the portion of the powered trajectory as it crosses those altitudes where contrails are normally produced. The graph above, which I calculated from that image and the position of the worldview-1 satellite at the time the image was taken, shows some of the points that any simulation of the rocket will have to fit. This, together with the splash down zones will add significant constraints to certainly the first stage. Some wonk-readers have wondered about both the direction and position of the observed contrail as projected against the Earth’s surface. This can be simply explained by the oblique viewing angle of the satellite (which had a latitude of 33 N degrees and a longitude of 126.6 degrees E and an altitude of 489.7 km) at the time the image was take and the fact that the rocket itself was over 4 km above the surface of the Earth.