contrails created by aircraft.
it's water vapor that has been condensed out by an aircraft's wing sliding the air that's flowing over it below it's dewpoint. this causes the water vapor to condense out as a mini-cloud. it can also be from water vapor in the engine exhaust.
if you ever hear people talk about 'chem trails', this is what they point to- insisting that it's a secret government agency dumping chemicals into the atmosphere. feel free to laugh at them.
Cloud seeding is something different and usually involves injecting small particulates for water droplets to nucleate on.
Where chemtrails are usually a reference to a particular chemical introduced to disperse into the air (not nucleate with). Often as part of a conspiracy saying all aircraft are taking part in blanketing the skies with whatever chemical agent is the flavor of the week. I’ve heard people say it’s mixed into the fuels, etc.
However, there are very rare instances where a plane (excluding crop dusters) will actually release chemicals via fuel into the air. When a plane has to make an emergency landing (especially right after takeoff) they may actually dump fuel in order to reduce weight and to minimize the explosive/fire hazard from the fuel.
Here’s a video by Captain Joe which covers contrails and fuel dumping
while cloud seeding is a thing, this is not what the conspiracy theorists are pointing at as 'chemtrails'. you can know that because cloud seeding kind of requires clouds to function. which, would obscure any smoke trails left by the silver iodide. cloud seeding takes already-condensed-out water vapor (aka, clouds,) and gives it something to attach to in large enough quantities that the droplets fall out of suspension- that is to say, they, uh, precipitate... and... uh... become precipitation... (aka, rain. or hail.)
this is done for a variety of purposes. the first is to cause clouds to precipitate in specific areas (I.E. LA does this over the San Bernardino Valley, to cause the precipitation to help with their hydro electric plants. And California does it up in the mountains to generate snow pack.)
Then there's the opposite- for example, around airports, they'll seed fog banks to get rid of the fog. or, in a bit more of a vane example, they seeded clouds to prevent it from raining on the Beijing Olympic's opening ceremony.
Those are contrails caused by aircraft.
Contrails come from one of two sources- either water vapor in the jet engine's exhaust (one of the products of combusting hyrdocarbons is water,) condensing into a stream of mini clouds.
The other source is caused by the flow of air over the surfaces of the plane. typically over the aerodynamic surfaces (though in the YF-23, it could have been caused by that valley between the engines,) What's happening here is there's water vapor in the humid air, and the dewpoint is such that, as the air flows around the wing- the air pressure changes, and if that pressure change is enough, it'll cause the humid air to momentarily drop below the dew point creating a stream of cloud.
If, any points to a contrail and says 'AH CHEM TRAIL' feel free to laugh at them. it's just water vapor that's been condensed into suspended water droplets.
(Re-Commenting, since my original comment got yeeted into the nether... sorry, this is in exact but it should at least have all the same information for posterity)
My brother has this completely redpilled friend. He's taken college level classes on aerodynamics and aerospace manufacturing (so have I). He's always pointing out the contrails and saying something about mind control or Bill Gates...
I always sarcastically ask him about what other medium would he expect them to be projecting the sky on. Gets him to shut up real quick. For an hour or so.... They really aren't that bright.
I've told one of them that if they really had a chemical that is undetectable and operates at such small doses, it would be much cheaper and easier just to have a few guys with a pickup truck dropping bags of it in the reservoirs.
Way easier to keep that under wraps than to deliver tons of it to all the world's airports and secretly load it onto all the planes.
Those are rasterizing lines, also called sketch lines, and they’re a common occurrence in the sky. Clouds can easily form in the air when water droplets, already chilled by the atmosphere, are slightly disturbed and ionized by turbulent friction. At about that height (it can be higher in some places), you get air passing quickly against the dome that projects the sky and stars. That friction can cause the water to condense, and lightly fall, obscuring the air and essentially making fog in the air, which is what a cloud is. What’s amazing about this process is that it is a naturally occurring effect, not regulated by the weather masters that control the sky projection and the air within it. Apparently there is no concern that we will see these imperfections, and know our secret rulers are also imperfect, and that knowledge means they can be taken down so that the common man can retake his destiny and rule this flat earth, using their weather machines not to create storms but to create a utopia where there is ample food, not tornadoes and hurricanes. We can even maintain these beautiful rasterizing lines to remind us of our conquest of these creatures and the rightful assent of man. Amen.
Chemtrails. The U.S. Government sprays them over us through ""pasenger"" (have you ever actually SEEN anyone get on them?) Planes to infect us with microchips and MIND CONTROL serum
They could be meteors, I've seen one or two leave a hard-to-see visible trail of smoke (I normally see them at night, making it hard to see the trail). However, as someone else mentioned, they could also be contrails left by planes or jets.
These are not meteors. I believe that you've seen those at night, but this daytime image is a contrail that appears to be glowing because part of it is in the sun while the rest is in the earth's shadow.