Where is the missle exhaust to the ground?
Over the horizon?
35 miles out?
60 miles out?
d=(1.50h).5
where d is the distance to the horizon (in miles) and h is the height above ground or sea level (in feet) of the eye of the observer."
For a 6' tall person the horizon is about 3 miles.
The photo at the start of the thread is taken from an elevated postion...say for argument... 1000'
in that case the horizon is about at 39 miles distance.
Given that the plane is at 37,000 feet it would appear above the horizon at a greater distance than say a ocean going vehicle.
The aircraft approaches the observer while maintaining a constant altitude, 37000', above sea level,
the observer though sees an increase in the planes azimuth with respect to the horizon as it approaches.