Above all else though, one of my favourite features has to be the continuous vapour trail your fighter craft leaves in its wake, allowing you to follow or avoid previous attack paths. (indiegames.com)
And those lovely vapour trails that jets leave behind in the sky? (thetyee.ca)
You can repeat William Herschel's experiment to show the existence of infrared radiation, examine the spectra of hot gases (identify the «mystery gas») and watch subatomic particles leave vapour trails in a cloud chamber. (newscientist.com)