If we have an incredibly powerful telescope, what is the earliest light we can see.?
146497
you could see the edge of the universe.  that was one of the things the Hubble space telescope was designed to do. \n\ntaking the age of the universe as around 14 billion yrs old you could see that far(in light years) into space.
1006967
Actually you could see right through the nebula. Nebulae are extremely thin and much clearer than the air on clearest day on Earth. The only reason we can see them at all is that they are trillions of miles thick. It wouldn't be like the movies at all, where the space ship is hidden in a dense fog, it would be more like space looking clear but the stars appearing somewhat dimmer. So you could just triangulate on a number of known stars outside the nebula to determine your position.
81268
The very first person to look up into the sky and see it.  Really!  It's so bright it can't be credited with a discoverier.
115588
look at a really really bright light
752656
The size of an object you can resolve with an optical system has a theoretical limit given by the wavelenght of the light you're using divided by the diameter of the optics multiplied by 1.22. If you plug the numbers in you find for a 1 foot diameter optical system at visible light (~400 nm) at an altitude of 100km, the smallest thing you could see is on the order of a foot, give or take (rough calculation). You could definitely not read a postage stamp or a wrist watch. Maybe a license plate with some bigger optics, but this is ignoring all sorts of atmospheric scintillation which screws things up.
939698
You actually want to know how much aperture a telescope needs to see another galaxy, not power. You see, not all galaxies are so far away that they're tiny and need to be significantly magnified, but galaxies are very far away and so from Earth they're very dim. The more aperture a telescope has, that is, the larger the diameter of their primary mirror or lens, the more light they can collect and the brighter images appear. After they have been brightened in a big enough telescope, it's typically best to just magnify them a little with a low powered eyepeice.\n\nTo answer your question, some galaxies, like the Andromeda Galaxy (M31). M81, and sometimes M33 are bright enough to see with the naked eye on very dark nights, provided you have very good vision.\n\nAfter that, the larger the aperture of the telescope you are using, the more galaxies you will be able to see. Because of this, most people who focus on deep space observing try to get the biggest telescope they can. To get super live views of most galaxies you should preferably not have anything smaller than 9.25" in aperture but you can see quite a bit with a telescope that's 8" in aperture, and you can even see quite a few galaxies with a telescope that's 4.5" in aperture but they'll typically look like small fuzzy wisps in that one.
679974
Telescopes!  When we can see various forms of light energy coming from stars and figure out how far away based on redshift and spectra, we can get an idea of how far away stars "can" be and how they are moving away from each other.  From that we determine the topology of the universe.
24731
You see in the past anytime you look through a telescope (or any distant object), as the light that is reaching your eye left the object a few seconds, minutes, or even years ago. You are seeing the object "as it was" when the light left it. If a star is 10 light years away, you are seeing it as it was 10 years ago, not as it is now. If it were to disappear, we wouldn't know about it for 10 years.
383249
The Hubble Space Telescope can see out to a distance of several billions of light-years. A light-year is the distance that light travels in 1 year. Since light has a speed of 186,000 miles per second (light can travel about 7 times around the entire earth in 1 second!), light travels about 5,865,696,000,000 miles in just one year. You can attach 9 more zeros to the end of this to get 1 billion light-years and another one for 10 billion light-years. The farthest that Hubble has seen so far is about 10-15 billion light-years away. The farthest area looked at is called the Hubble Deep Field.
949144
Tonight and tomorrow night. Look after midnight though since the meteors will be arriving from space on the dawn side of the Earth. Before midnight you are on the "back" side of Earth and won't see the meteors. Just before the start of morning twilight is the best time to look. Other than that, they should be visible from any place on Earth.
851325
I think the rings of Uranus are too tenuous to occlude starlight to a detectable degree. I don't believe those rings were actually discovered until we sent out probes to a point where they were directly visible. \n\n30 NOV 06, 1953 hrs, GMT.
436768
it is only an infinite refrexions of light. the device used to do it is called KALEIDOSCOPE
900039
A dobsonian telescope will give you the most telescope for your money. These are Newtonian reflectors on simple alt-azimuth (tilt & swivel) mounts. Get as much aperture as you can afford and handle. More aperture means being able to see fainter objects and finer detail. Many people find an 8" scope a good choice.\n\nOrion Telescope & Binoculars has some good beginner dobs. Zhumell is another brand with good values in this area.
215954
The can't see back to the big bang, but they can see its signatures and get a good idea of what it was exactly. The earliest signature they've seen back so far is ~380,000 years after the big bang. There probably are rays of light from 15 billion years ago still moving around, but if inflation is correct, then the actual image of the big bang has already passed across the universe very early in its history (solving the horizon problem) and we will never see it.
1136943
M31, the Andromeda Galaxy, is the most distant object easily seen with the naked eye. In a very dark sky, you may be able to see M33, which may be 3 million light years distant.\n\nIt's a little more difficult to determine what is the  most distant individual star that can be seen with the naked eye, as it is apt to be some faint, nondescript star. Also, it is difficult to accurately determine the distance to a single star at distances over 1500 light years. P Cygni, a fifth magnitude star in the constellation Cygnus (the Swan or Northern Cross) is a very luminous star possibly 6000 light years away. This is probably a reasonable approximation of how far away a star can be seen. Note that this is still in our Milky Way Galaxy, which is around 100,000 light years in diameter. However, you might be able to see a supernova in a nearby galaxy.  SN1987A in the large Magellanic Cloud reached third magnitude, and it was fairly dim for a supernova.  (About magnitudes: six is about the dimmest visible, smaller numbers are brighter. The brightest star, Sirius is -1.)
671170
Are you including the stars that are being created, as well as those that do not actually exist anymore but have died out/ supernova'd/ etc. that we are just still seeing since the light has to travel so far?  \n\nI would be interested in how you determined this number ^_^
585565
Spectroscopy (splitting the light into its constituent colors) and photometry (counting up how much light there is).  We can measure how far away they are via redshift, and from that and brightness measurements calculate their absolute luminosity (how much energy it puts out per second). The size of the emitting area can have an upper limit placed on it by watching how fast it varies in brightness.  (Approximately the speed of light over the brightness change timescale).  \n\nSo, you are emitting "x" amount of energy in a volume of "y" size.  The number of stars necessary to produce that sort of energy collectively would have a mass large enough that this superdense cluster would be inside of its own Schwarzschild radius (ie be a black hole).  \n\nSo you need some more efficient way to produce energy than fusion in stars.  The only astrophysical phenomenon known to do that is the rapid loss of a large fraction of  gravitational potential of mass (drop something onto something dense enough that it would reach an appreciable fraction of the speed of light. As it interacts with other matter on the way in, it heats up and glows.)  This requires either black hole or neutron star type gravity.\n\nI suppose you could hypothesize a dense cluster of a zillion neutron stars all accreting matter, but that is pretty contrived compared to a single large blackhole.  You can probably show that their accretion disks would result in enough drag as they zipped around one another (and consequently through one another's accretion disks) in this small volume that they would all be coalescing and collapsing into blackholes in a pretty short timescale anyway.\n\nIn short, nothing so small and so bright could be anything BUT an accreting supermassive blackhole.