Why does a comet seem to give off a light of its own?
442669
A comet is made up of rock, dust and ices that freeze as the comet moves away from the sun. When it gets closer to the sun the ices and rock will burn due to solar radiation. A comet does not always have a tail!
492251
Friction with air.\nBecause of accelertion due to gravity(g=9.81 m/sec^2 at the equator) the meteor travels so fast on entry into the atmosphere, that is heats up due to friction and the volatile matter in the meteor burns off, leaving a bright trail of light if it's a t night, what is know as a shooting star. \n\nst
72663
Its a cute question. :-)\nLet me explain it this way.\n\nShadows arent necessarily objects themselves. \nThey are just a patch of surface, which dont recieve direct light from the source (sun, lamp etc), but only recieve the scattered rays of light. \nAnd for this reason, these patches are dimly lit, making it look darker than the surrounding, which in our daily terms is 'black'. :-)
563434
a meteor is headed toward earth so it hits the atmosphere, so you never see it again. the comet orbits the sun, so it does not burn up. the reason it does not burn up when it gets to close to the sun is because it orbits it, it does not crash into it.
427235
Dust particles and ionized gas from the comet.  The dust and gas each form their own distinct tail.
25683
It bounces around and out of the room. Since this happens at the speed of light, you don't notice a gradual fading of light so much as a sharp transition to darkness.
133450
well, the usual rules of physics at such speed don't apply. so when you turn the headlights, the light will travel from them at approximately the usual speen of light, and i guess you won't notice anything unusual..\nfor more information check the subject at wikipedia. and the following subject: Constant velocity from all reference frames
139013
The main reason that heavenly bodies appear to twinkle is because of materials between them and your eyes - normally it's atmospheric interference which makes them appear to distort and shift. This actually happens with planets as well, but it's less obvious because they appear larger in the sky and so minor distortions don't have such an effect.
497011
It works by having little mirror slices at different angles. As light is reflected off the orb, the little slices separates the light into several colours briefly and the process is repeated.
22142
There is not a speciic comet that you will be able to see soon. Expect some meteor showers to be coming in your area. A good site that I recommend is: www.heavens-above.com
1046132
A star produces it's own light, a planet does not, it merely reflects the light of the star. Because a star producing it's own light, it will glow brightly, dim, then glow again........this is the twinkling effect, much like the flame from a match, or any burning fire. :)
881129
At any given time, stars in the solar neighborhood have typical distances to each other of a parsec or so (a few light years). But since all stars move in random directions, occasionally a star will pass (much) closer to another star. When a star makes a passage close to the sun, it still stays far outside the planetary system.  But such a passage may perturb the comets in the Oort Cloud, spread out over an area more a thousand times larger in diameter than the planetary system. While a close passage typically lasts only ten thousand years or so, it may trigger an increase in the frequency of arrival of comets in the inner solar system, which can last for a few million years until equilibrium in the comet cloud is restored again. \nDuring such comet showers the probability of impacts of comets on Earth is enhanced; depending on the type of perturbation by a passing star it can even be greatly enhanced.
489247
Our eyes perceive energy in the visible light range that is either emitted from a source, or reflected off an object.  In space, the light sources are stars, like our Sun.  Objects like planets and comets and asteroids and dust, reflect the light emitted by the stars.  Since space is a vacuum, there isn't anything to reflect the light, therefore it is black.
556627
A shooting star is not actually a star.  It is a meteor.\n\nA meteor is the light you see when a meteoroid comes in contact with the Earth's atmosphere.  The "ram pressure" of this object, which is usually rock or rock + iron, smacking into our atmosphere creates heat, and the meteor begins to burn.\n\nWhen our Solar System was forming, there was a lot of junk left over.  If our Earth's orbit intersects with this junk, it will burn in our atmosphere.  \n\nMost meteoroids are tiny (dust and pebble sized) and burn up before they can reach the Earth.  Some hit the atmosphere the wrong way and skip across it like a stone thrown to skip across a lake, and eventually escape, albeit somewhat smaller now.  Some manage to hit the Earth.  There's one in the Adler Planetarium in Chicago that is huge, about three feet long and a foot through the middle.  (When they make it to the groud they are called meteorites.)\n\nMeteor can come one at a time, but there are also meteor showers, times during the year when you can expect to see a lot of meteors (10-80 per hour).  This happens when the Earth passes through the trail left by a comet.  Meteor showers are named for the constellation from which they appear to radiate.  The most famous is the Perseids, which radiate from Perseus, and are associated with the comet Swift-Tuttle.
76701
Yes.  I've seen them a couple times.  I think they're actually meteors entering the earth's atmosphere. (They get set on fire and you see the trail) Sometimes there are meteor showers and you can see a whole bunch of them at one time.  Watch your local newsweatherman enough and he'll let you know.
934952
They burn up in the atmosphere.  Meteors are brilliant flashes in the night sky. They travel 60,000 km per hr.  At those speeds friction with air particles vaporizes an average size meteor in less that a second. The flash of light is caused by the intense heat of vaporization. Only on rare occasions a chunk large enough to survive the plunge hits the ground.  This is called a meteorite. The largest meteorites surviving the plunge do damage the surface of the earth and cause craters but this  rarely ever happens. You probably wont ever see it in your lifetime.
725184
Great question. The light from the Sun is only part of the answer. The Moon has had its surface  pounded by meteor impacts. These throw up molten droplets of rock which cool and solidify as small glassy spheres and drop back onto the surface, As there is no atmosphere on the Moon the particles don't get blown around and abraded (which would make them dull). So a lot of the Moons surface is covered with a layer of highly reflective particles and thats why its so bright.\nThe lines painted down the road work on the same principal. The paint contains small, round glass particles to make it highly reflective whereas the road remains dark.