If you look close the com trail has little puffs(donuts on a rope) in it caused by a scramjet or pulse detonation engine. This new engine is on the ARORA spy plane,which is capable of hypersonic speed,and can skip along the top of the earths atmosphere . Now if you notice the sun is directly behind it and if its that high, the dark line may be its shadow or the shadow of the comtrail in the atmosphere (between the stratosphere and the mesosphere).
God is great, beer is good, and people are crazy.
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