My photo is of the smoke train taken about 30 seconds after the fireball. It is two puffs that , over time grew puffier and joined together. I could see them for at least five minutes maybe longer. It's hard to say because I was travelling east did not stop to watch them fade away. I don't understand the question about the train in terms of degrees equaling length but you can look at the picture.
Terminal flash
Observation
Yes
Remarks
The bright light caught my eye. I watched to see that it was in fact a moving object and then a few seconds later it grew very bright and big and then just shattered leaving the smoke.
