Is sky an empty space or has any material besides the planets stars etc.,?
494685
You must not be a native English speaker. I think what you are asking is:\n\n1. Is outer space empty besides planets and stars...?\n2. How and when did the universe come into existence?\n\nNo; space is not empty it is filled with gas and dust(known as the "interstellar medium"). The density of the ISM varies widely between a few to hundreds of molecules per cubic meter. Even intergalactic space is not empty. It also contains traces of gas and dust. Latest estimates are 15 billion years for the age of the universe
602526
No body know for certain. However, the universe is so vast, with so many celestial bodies that it seems rather improbable if the only place in the whole mutiverse that harbors life is planet Earth.
575853
that means empty space
320913
Yes, space is big. I mean really really big. You can't possibly imagine how absolutely huge it is. Also it's dark, cold and empty for the most part.
312310
Is there such a thing as close by planets?\nWith all that we see in the night sky, not just stars but galaxies as well, what are the chances that we are alone in the universe?\nThere has to be intelligent life out there. We are all just too far from reach of each other. And most likely, other intelligence would be like us and send probes. Living beings could not survive the long travel, space probes could.
1026088
sky is just a small portion of the universe.\nit cud have a pillar if one cud go to the ends of the universe.. but even the most elaborate and sensitive radio telescopes cant reach all that is up there.. \n\nthere are more stars and galaxies un-named...... and counting....\n\nil let u know once i found out what makes the sky stands up there... with or without pillars. \n\nafter a million light years.....P
573669
Oh absolutely.  In fact, I have long toyed with the idea that Earth is 1st grade - 2nd grade is on Mars maybe and it's about 2 civilized planets near one another, 3rd deals with multiple solar systems, etc.\n\nI think it is very hard to look up into the night sky and see all those stars and planets out there and think that we are the only ones.  It just doesn't make sense.  Why would anyone create such a vast universe just to look pretty in the night sky?
1113645
A clear cloudless day-time sky is blue because molecules in the air scatter blue light from the sun more than they scatter red light.  When we look towards the sun at sunset, we see red and orange colours because the blue light has been scattered out and away from the line of sight.\n\n\nBecause the universe is not infinitely old, that puts a limit to how long the\nlight from all those stars can have travelled. So some of the light has not\ngotten here yet. Because stars do die out, that means that their light dies\nout too - which means that we may get the light from some stars at one time,\nand the light from some other stars at a different time, but not all the \nlight\nof all the stars that everywhere put together. Finally, because the \nuniverse is\nexpanding, the light gets weaker before it gets to us. All in all, this means\nthat there is not enough light from all those stars to make any point in \nspace\nbright.
1021700
such a waste of space if we were alone.\n\n if you could just imagine yourself looking on our milky way from another outside.. \n\nhow infitestimally small we truly are... we are nothing but dust on a small rock revolving a small star..
556010
The sky is (roughly) that part of the atmosphere or of outer space visible from the surface of the earth (or any other planet; see Skies of other planets). Birds, airplanes, and kites are often considered to fly in the sky. It is difficult to define precisely for several reasons. During daylight the sky has the appearance of an opaque blue surface, but this is the result of the air scattering sunlight. [1]There is no "blue object" above the earth in any normal sense, so it is hard to say what object the sky is. The sky is thus sometimes defined as the denser gaseous zone of a planet's atmosphere. At night the sky has the appearance of a black surface or region scattered with stars. But if we then say that the sky is the entire visible universe, it would not be the same thing we see during the day. The color of the sky is a result of diffuse sky radiation. On a sunny day the Earth sky usually looks as a blue gradient — dark in the zenith, light near the horizon (due to Rayleigh scattering). It turns orange and red during sunrise and sunset, and becomes black at night.\n\nDuring the day the Sun can be seen in the sky, unless covered by clouds. In the night sky (and to some extent during the day) the Moon, planets and stars are visible in the sky. Some of the natural phenomena seen in the sky are clouds, rainbows, and aurorae. Lightning can also be seen in the sky during storms. As a result of human activities, smog during the day and light radiance during the night are often seen above large cities (see also light pollution).\n\nIn the field of astronomy, the sky is also called the celestial sphere. This is an imaginary dome where the sun, stars, planets, and the moon are seen to be travelling. The celestial sphere is divided into regions called constellations.\n\n\nSky in religion\nMany cultures ascribed strong religious qualities to Earth's sky, believing it to be the home of the heavens and various deities. Among the Chinese, in certain situations, sky means god. For example, people may say "They became friends after several fights: this is the idea of the sky" or "Why does the sky always fool me?" Some religion and art historians believe that in Christianity, in particular, the connection between heaven and sky arose because of a medieval painting technique, where different places were drawn separately on the same picture. Heaven, a different and more important world, was usually painted above the earthly world and was separated from it by clouds.\n\n\nExpressions\nA pie in the sky is something that is wanted very badly but is unobtainable. \nWhen someone's assumptions or premises concerning a particular subject seem to be radically different from everything you know and recognize about the world, you wonder what color the sky is in their world. \nSimilarly, because the blue hue of the sky during daytime is such a universally observed and understood phenomenon, people say "as sure as the sky is blue" to mean that something is an indisputable fact. \nBlue skies are evoked as a symbol for good times, optimism and emotional peace. \nTo be sky-clad means to be in the nude. \nSimilarly, to go skying is a euphemism for stripping or streaking. \nTo show that there are no limits on what we can discover or accomplish, you can say, "The sky's the limit!" \n"Blue sky thinking" means coming up with a host of ideas without being restricted to what is practical (similar to brainstorming); in particular, an optimistic assumption is made that there will be no obstacles or opposition to implementation of the ideas. \n"The sky is falling" is a common expression that is used when any sort of disaster is occurring. This came from the fable Chicken Little
929659
reflection of light\n\nDuring daylight the sky has the appearance of a deep blue surface, but this is the result of the air scattering sunlight. [1] There is no "blue object" above the earth in any normal sense, so it is hard to say what object the sky is. The sky is thus sometimes defined as the denser gaseous zone of a planet's atmosphere. At night the sky has the appearance of a black surface or region scattered with stars. But if we then say that the sky is the entire visible universe, it would not be the same thing we see during the day.
630601
There is some gas out there, but it's very sparse:\n\nhttp://hypertextbook.com/facts/2000/DaWeiCai.shtml\n\nThe interstellar medium is mainly made of lone hydrogen atoms. They do not even exist as pairs as they do on earth. I mentioned before that space is filled with hydrogen atoms. The actual density of hydrogen as it exist in interstellar space is on the average of about 1 atom per cubic centimeter. In the extremes, as low as 0.1 atom per cubic centimeter has been found in the space between the spiral arms and as high as 1000 atoms per cubic centimeter are known to exist near the galactic core.
829244
I know of no reputable astrophyscists who claim space is empty.  In fact, Brian Greene's "Fabric of the Cosmos" spends a lot of time talking about the stringy stuff that fills space.  The Higgs Field is also a something that fills space according to some theories.  Further, mass bends space, bent space has been observed; so it seems logical that space is a something (not a nothing) that can be bent.  So your premise that space is not empty is widely accepted.\n\nAlthough there are some short-lived massless quanta that can penetrate great distances, most cannot.  And the great distances have limits.  Even neutrinos have a limit on how deep they can penetrate a mass.  Gravity, on the other hand, is not diminished by interceding mass.  We are affected by measurable gravity in the deepest, darkest caves, for example.  So none of the known and theoretical quanta, save one, exhibit the characteristics of gravity.  \n\nThat one exception is the graviton, which is predicted by string/M theory.  The graviton has never been observed; so its existence has never been proved.\n\nSo your supposition that the effects of gravity are due to bombardments of quanta of some sort does not generally stand up to the evidence.  The one exception is the graviton, which is strictly theoretical and may not exist.
1049200
There's space up there. And since space is limitless, I guess sky is so too!
737558
space is not a fluid that planets need to float in it is just plain emptiness.
629153
The sky is what people back in the day called what they saw above them because they didnt know what it was..\n\nnow that we know, we know that what we see as blue sky is just refraction of light, and when there is no light ( night ) we just see things out in the universe that reflect light(moon) or emit light ( stars ) \n\nso the sky doesnt really exist, what it is is gases that refract sunlight during the day, and let you see through at night
612672
well unfortunately, outerspace is a whole lot of nothing, so it doesnt have to take up any space.  granted there are molecules floating around out there, but for the most part there isnt any matter in empty outer space