with the sun being so huge and hot, why is it dark and cold in outer space? how can this be?
It’s only dark in the places where you don’t see a light source. But since most of space is, well, space, what would you expect to see? 
The reason it seems light everywhere during the daytime on earth is that you’re seeing the sun’s light reflected off everything around you. If you’re floating in empty space, there isn’t anthing (except the odd dust particle) for light to reflect off of. You see each star (the sun is just a star) as a light source and you see things like planets because of light reflcted off them. But space itself doesn’t have anything to reflect the light (otherwise it wouldn’t be “space”).
I forget the cold part…
Heat is just atoms moving around. No atoms, no movement, no heat.
Because outerspace is a vacuum, it can be neither hot OR cold because the notion of temperature only applies when you have matter. Objects in outer space can be cold but they can also be hot too. Satellites which have their face towards the sun can get very hot. But the side not facing the sun can also get very cold because there is nothing heating them. As for why it’s dark, its the same deal. If you are not facing the sun, then you are not getting any light.
What about the dark matter?
::d&r::
The other responders are right to point out that if you look away from the sun, you don’t see the sun’s light.
However, I feel the need to play Devil’s Advocate and throw a monkey wrench into their carefully-wrought works:
How come you aren’t flooded with light from all the other stars out there? The sun’s not the only light source in the universe, you know. All your answers conveniently omit this fact.
That’s no monkey wrench. That’s Olber’s Paradox.
Dammit, you gave them the answer 
Note what I said in my first post
It’s not unlike what you see on a moonless night, away from a big city here on earth. You can actually see quite a lot from starlight alone.
But you’re not flooded with light for the other reason that I said in my first post:
To be more specific, you’re seeing the sun light reflected off the atmosphere, and that is more intense than the light from the stars, hence you don’t see them. If you’re standing on the moon (which has no atomsphere to speak of), you’ll see a lot of “dark” out there even during the daytime.
Of course, to the man with microwave eyes, space isn’t black.
The darkness observed between stars was once used as proof tha the universe is finite, if the universe was infinite every spot would have a infinite number of stars in it, so the sky would glow uniformly. When Hubble discovered that the universe is expanding this proof was invalidated, at a sufficient distance light can never reach us, currently its believed that the universe is infinite, but we can only see part of it.
Believed by whom?
And just to add to that, due to the expansion of the universe, matter is constantly moving outside our horizon of visibility, which means there are fewer and fewer light sources that can reach us over time (and no this doesn’t mean the galaxies are traveling faster than the speed of light, the expansion is different than objects moving away from each other in a static universe).
You can still define radiation temperature. Which is basically the equilibrium temperature of an object placed in that environment.
And by that definition space isn’t very cold, unless you’re in the shadow of something and can’t get heat from sunlight, or you get very far from the sun. If you placed a piece of rock in orbit around the earth, its temperature would be close to what we consider room temperature.
Interestingly enough, there’s enough dust floating around the ecliptic (average plane that the planets orbit around our sun) that it can be seen on a dark clear night: the zodiacal light. It’s been proposed to send some astronomy satellites as far away as Jupiter’s orbit because there is far less zodiacal light to interfer with observing very faiint deep space objects.
Was Edgar Allan Poe really that deep? No offense to the man, but I don’t envision him pondering the speed of light back in the 1800’s. Is he really the “first person” to propose the idea, or was he just repeating something that was being bandied about in the science world at the time?
Poe may be better known today as a drug-addled horror writer, but he is one of the writers often cited as a Father of Science Fiction.
Here’s the Straight Dope on Olber’s Paradox:
I don’t know of anything blacker than the CMB, other than a sufficiently massive black hole. Even there, small black holes can have significant graybody factors, and nobody’s ever observed the spectrum of a black hole.
John Mace, the null hypothesis among cosmologists at the moment is that the Universe is in fact infinite. This is more a matter of Occam’s Razor than of actual observation, though: We observe space to be flat, flat space of trivial topology must be infinite, and we observe no evidence of nontrivial topology. It’s still quite possible that either space is not flat or that it has a nontrivial topology, but if so, it’s on a larger scale than we can observe. I don’t think there’s actually any observation which could in principle be made which would prove that space was infinite, though.
He does indeed appear to have been the first to suggest the particular point: that a finite speed of light in a finitely old universe solves Olber’s Paradox, even if the universe is infinite in extent. That said, one shouldn’t overstate the scientific sophistication of Eureka: A Prose Poem, the lecture and essay where he made it. His own enthusiastic speculations aside, the content - including stuff like the finite speed of light and ideas about the structure of the Universe - was entirely what Poe had picked up from the popular science books and lectures of his day. In some cases, it’s even known with some certainty what those sources were.
I’d call his originality on the specific point a lucky hit, though an astute one.
There are plenty of odd arguments in the essay. At one stage he even claims that the Moon is self-luminous, on the grounds that it can still be seen during a lunar eclipse. That’s somewhat behind the times for 1848.