Was it noisy when the rocket flew over?
The Falcon 9 launched at a site north of me and headed further north, since the ISS orbits Earth tilted 55 degrees to the equator so it didn't fly over me. That picture is actually looking "up the skirt" of the exhaust as it heads away from me. The launch rumble reached me after about 2 minutes and sounds like a heavy truck passing on a road not so far away.
That's amazing view of it in the night sky!
Dawn sky, which is important. Below and to the left of the great, ethereal haze of the exhaust, there's a squiggle of a cloud. That was a conventional contrail as the rocket launched vertically and climbed above the atmosphere. You see those contrails all the time, night or day.
But once a rocket gets above the atmosphere, the exhaust of water vapor and carbon dioxide just spreads out endlessly in a very faint haze of steam. During the day, it's invisible against the blue sky. During the night, there's nothing to light it up.
At dusk and dawn, when you're on the ground in darkness but the exhaust is catching the sunlight it produces that fantastic, huge exhaust cloud.