The cloud-like lines we frequently see trailing along planes make cool pattern in the sky and make for incredible Instagram photographs, yet have you at any point considered what they really are?
At the point when Austrian physicist Robert Ettenreich previously saw them in 1919, he portrayed them as 'the condensation of a cumulus stripe from the exhaust gases of an airplane', noticing that it was visible for quite a while.
In spite of looking like smoke or a huge cloud, these trails are for the most part condensation, as opposed to the familiar exhaust fumes we see from cars. Or on the other hand, in the aerospace industry, they have a more specialized name of 'condensation trails' or 'contrails'.
