I hate to say it, ens, but your photoshop has failed you in the smallest way. Look at the 1px bit on the leftmost point of the sphere. That should be fixed with the adding of an atmosphere though.
I don't like the gradients you used on the leftmost meteor's trail. It's way too long and should become skinnier away from the falling object. The air distortion around it needs some work too, a bit mor orangish tint and larger fireball at the front. The impacting one looks very nice, though, hope to see something real nice come of that.