Contrail

Heard this word whilst watching the news about the recent  "Mystery missile" seen off the California coast. I always loved looking at them in the sky and always wonder where the aircraft is that caused it.

Whilst I'm a big fan of the X-Files I didn't think it was alien!

CONTRAIL - Contrails are man made. A shortened form of "Condensation Trail", a vapour trail left behind by jet-engines. Atmospheric conditions have to be exact for a contrail to appear -40F, high humidity. They only appear above 8000 meters (26,000 feet).

These days, when we are so environmentally conscious, Scientists are looking to these contrails and there effects. Some say they cause “regional-scale surface temperature” changes.

For a much fuller explanation see the page Wikipedia "Contrail" explanation