What is the purpose of rockets making white smoke lines all over the sky?
912321
Are you sure those are really rockets?  There are not that many launched, you know, and the tend to go up quite quickly so unless you are down range from a rocket launch pad, you probably never seen a rocket.\n\nI tend to have a hunch that what you are talking about can be contrails from high altitude airliners.  If this is so, and then they can be in all directions (while rockets are essentially launched towards the east to get an extra nude from the earth's rotation) this is not smoke, it is just the engine exhaust, a mix of carbon dioxide and water vapor from the combustion of hydrocarbon fuel, that cools in the very chilly air at those altitude (10000 m and above).  The ice crystals form and look just like a cloud that can dissipate at varying rate depending on how humid it is up there.
817981
As others have said, it's all about speed. \n\nIt's a minor point really, but it's a common misconception that it is the friction with the air that causes objects hitting the Earth's atmosphere at high speed to heat up. Actually it's not friction. The heating up is caused by the fact that the air in front of the object cannot get out of the way fast enough, so it's gets compressed in front of the object. As the air gets compressed the pressure rises and as the pressure rises so does the temperature. This is what causes the burning up effect.\n\nWhen a space craft is blasting off into orbit, as its speed rises it's also gaining altitude. At higher altitudes the atmosphere is less dense, so this compression of the air in front of the space craft never becomes a problem.\n\nIf a space craft used its rockets to slow its decent back to Earth then it wouldn't have any problems with burning up on re-entry. The reason they don't do this is because of the weight of the fuel that would be needed to do it. With current technology, no spacecraft could carry that amount of fuel and still be able to get into orbit.
599392
Smoke is a suspension in air (aerosol) of small particles resulting from incomplete combustion of a fuel. It is commonly an unwanted by-product of fires (including stoves and lamps) and fireplaces, but may also be used for pest control (cf. fumigation), communication (smoke signals), defense (smoke-screen) or inhalation of tobacco or other drugs. Smoke is also sometimes a component of internal combustion engine exhaust gas, particularly diesel exhaust.
1163910
Red moons rising are actually fairly common usually as a result of large amount of dust, smoke, or other pollutants in the air
430419
Have you ever looked at the sky and seen a shooting star?\n\nThese are meteors burning up as the enter the atmosphere.  Is this what you are talking about?
112412
Hard to say form such a vague descrition. As omegawulf666 says, they could be jet contrails if you are only seeing one at a time. \n\nOr you could be referring to radiatus clouds, which form multiple parallell lines (although they often seem to converge on the horizons, like train tracks).\n\nThe one thing they defintitely are not are jet streams. A jet stream is a type of wind. You can't see wind.
206705
It isn't but there are some particles in the atmosphere that are flamable, but they are so widly spaced you won't even see a fireball, Anyways oxygen has a special chemical compound that feeds fire, but thats all, its not "flamable" its just food for fire.
652146
It is a large vapor trail from a jet airplane with chemicals in it.\nPictures...\nhttp://www.endtimesevents.com/CHEMTRAILS.html\nIt is quite an issue and some people are very upset...\nhttp://www.chemtrailcentral.com/
488514
What are ChemTrails?\nThe chemtrails theory is a group of theories regarding what are claimed to be unnatural contrails from aircraft. (Contrails are formed by condensation of water vapor in the aircrafts' exhausts.) Chemtrails are some kind of chemical or biological agents being secretly released. As things stand, this currently falls under the category of conspiracy theory. \n\nAre they real?\nFor the most part, the lines in the sky we see are contrails, but chemtrails are an unfortunate reality. They are thicker than contrails and sometimes remain in the sky for hours after thickening. They appear cloudlike and low in the sky. There have been incidents where airborne aluminum, barium, calcium, magnesium and titanium, and "microscopic fibers" were found as a result of chemtrails. Regardless of denials, this is a fact. Some people say it's part of chemical warfare but in reality, it's a form of clear-cut air pollution and illegal dispersion of wastes. Of course in the future, this type of practice could and may be used as an exotic weapons system for biochemical attack, but the chemtrails we see now are not dispersed for that purpose.\nHow much do they endanger the average person?\nIt depends on what type of toxins and pollutants are released and how close one is to the actual dispersion. Each incident is specific in and of itself. Weather and wind conditions also affect how the toxin are spread and received.
438403
You can use air compression if you can't find fireworks.  Rig something to blow its top and throw some top cover into the air.  Sound effects will add to it.  The container could contain smoke that you've trapped in it to release.
237061
Hey! I resent that answer above! It's something you should be concerned about, basically all the fumes people are emitting into the atmosphere (from factories, cars, etc.) are getting trapped in our atmosphere and heating the entire planet! This really shifts the balance of everything, there are many animals that can't live in the new heat they're not used to! If this keeps up, the earth will be smeltering!
861784
Not necessarily true. When I was in the Air Force, I was a weatherman. We got sent to St. Louis to some air pollution research, which meant sending up mini weather balloons. At night, we sent the balloons up with a small light attached to them so we could track them. We had about 10 teams scattered over St. Louis doing this, and after the first night, the newspapers read that there were all kinds of calls made sighting lights in the sky.
48781
kinda, but it isn't a star. it's fragments of space debris, meteors etc, burning up whilst passing thru the earth's atmosphere. From the ground it appears like a star shooting across the sky, hence it's name.
841719
sorry for laughing but I know everything can be used with math. Those rockets, how long is goes up, where it lands the wind , angle bla/bla
780823
Could be a strange mirage. Sometimes weird mirage can project skyline of cities beyond horizon or just strange shapes in sky when atmosphere refract lights in unusual ways.
1061390
It's caused by ice particles in the sky, particles which make up the cirrus clouds. Light combined with the ice particles create the halo that you see around the moon and sun.
1106194
Explosions in Space\n\nhttp://www.madsci.org/posts/archives/1998-08/899689009.Ph.r.html\n\nMain excerpts:\n\nOn Earth, the interaction with the surrounding matter, be it air, water, or whatever, means that the initial energy is very quickly, in a few milliseconds, spread out over a fairly large amount of matter, no matter what the nature of the explosive. This material, typically air, forms a luminous fireball that expands at the speed of sound in the air that has been heated by the explosion, which is faster than the speed of sound in ordinary cool air. The result is a shock wave at the surface of the fireball. As the fireball expands it compresses and heats the surrounding air, while losing energy by radiation and also because of the work it is doing on the outside air, all of which causes it to cool. Eventually it cools to the point where it is no longer luminous, the shock wave moves out ahead and makes the BANG! that we hear and that may knock down buildings, and a cloud of swirling debris, smoke, and maybe brownish nitrogen oxides are left behind.\n\nIn space, the first few milliseconds proceed as they would in air (say), but then the transfer of energy to the surrounding air never takes place. As a result the initial small, intensely hot fireball simply keeps expanding at very high speed, and the expanding gases and any fragments fly off in straight lines. The fireball cools by radiation at first, but as its density drops it becomes so transparent that radiation is suppressed. For a chemical high explosive, the expansion speed would be a few thousand feet per second. So for a moderate size explosive -- say 1 meter across -- the products will expand to 100 meters in probably less than 0.1 sec, meaning the density will have decreased by a factor of a million, and the visible explosion will effectively be over. Visually the effect would be of a very brief, brilliant flash in a region only a little bigger than the actual extent of the explosive material. Of course there would be no billowing swirling smoke, and any fragments would almost certainly be moving too fast to be visible. The effect would probably be something like that of a big flashbulb.