Great balls of fire !!!

[AVGWarhawk]

Originally Posted by GoldenRivet

That is the setting sunlight striking the contrail of a large twin engined jet aircraft, the sunlight in this scenario is refracting off the thickest and most humidified portion of the contrail as it leaves the engine and trails several hundred ft behind the aircraft. As the humidity of the contrail dissipates, less light is refracted.

Another airplane exhibiting the same phenomenon is visible to the right heading in another direction midway through the vid.

I've seen this happen hundreds and really probably thousands of times in my aviation career.

its nothing to get excited about.

No way. Those are UFO's for sure.