what are the lines that form in back of jets and stretch from horizon to horizon?

Chemtrails.

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Chemtrails.

We put a mix of aluminum and barium into the jet fuel so the vapour expended from the engine combustion will attach to the condensation nuclei and make persistent contrails. This blocks out the sun and offsets the increasing temperatures due to global warming.

Dimmer skies for a brighter future. Spray on, brothers and sisters!

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They are called contrails short for condensation trails.

A molecule of hydrocarbon fuel, such as jet fuel, is made up of long chain of Carbon and Hydrogen atoms. During the combustion the molecule breaks up and Carbon combines with the Oxygen from the air to from Carbon Monoxide and Carbon Dioxide. Hydrogen also combines with Oxygen to from water vapor. At typical airliner cruising altitudes the temperature is usually cold enough that the water vapor flash condenses and the condensation forms a trail behind the plane.

What happens to the trail depends on the conditions aloft. If the air is calm, the trail will persist for a long time. If the air is turbulent the contrail dissipates quickly.

Planes follow set routes across the sky, much like drivers follow the interstate highways across the country. If a plane flying along such route leaves a contrail behind, the wind will often blow the contrail off to the side. Another plane following along the same airway a few minutes later will leave another contrail that to an observer on the ground will appear as parallel to the first. Where these air routes cross each other, an observer on the ground may see a tick-tock pattern of contrails in the sky. These regular contrail patterns, combined with total lack of understanding of atmospheric conditions and chemical and thermodynamic processes involved in the combustion of hydrocarbon fuels give raise to a whole chemtrail conspiracy cottage industry.

You can see the same phenomenon if you watch the car's exhaust on the cold day. When the car is started, the water vapor starts condensing in the still cold exhaust system and will come out of the tail pipe as water droplets. This is why, by the way, the car mufflers have tiny weep holes on the bottom to let the condensate drain out of the muffler. As the engine continues to run, the exhaust system warms up and you start seeing a small cloud of water vapor coming out of the tail pipe. As the exhaust system warms up even more, the cloud disappears because the vapor dissipates before it can condense into a visible cloud. However, if the temperature is cold enough you can see the condensation even after the exhaust system reaches its normal operating temperature.

Those are called "con trails" or condensation trails, its made because of the sudden temp. change from the exhaust coming out of the engines. its very cold, the higher up you get away from the earths surface. all the way down to -67 degrees. What you are seeing is ICE CRYSTALS and the closer they get to earth, the warmer they get, and they thaw out and vaporize.

Vapour trails produced by the engines when burning fuel. Kerosene produces approximately it's own weight in water vapour when it burns.

Contrails. Moisture condenses in the exhaust plume of the jet engines, basically creating man-made clouds.

depends contrails disappear within seconds/mins and start after plane chem trails start at plane and dont disappear for up to 24 hours later

vapor trails