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Deepest Optical Image Of The Universe To Date

fenimor writes "The deepest optical view of the universe, obtained by Hubble Space Telescope, may turn out to be some of the earliest star-forming galaxies. The telescope has looked 95 percent of the way back to the beginning of time, to glimpse whether the hottest stars in these early galaxies may have provided enough radiation to 'cool' the universe after the big bang."

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  1. Actually, you are correct... by j_cavera · · Score: 5, Interesting

    This is not a paradox, rather just a way of looking at it that is different than what you are used to. The universe at the beginning of time, existed as a point (more or less) that expanded (somehow) into what we see today. As you look out into the universe, you also look back in time. The farther back you go, the smaller the universe was.

    By logic, if you could look all the way back to the big bang itself, you would see a point of light. And this is where your percieved paradox occurs. But this is actually the correct way of thinking about it, because time = distance. So where does that point lie? Everywhere, at a distance of 15 billion (give or take) light-years from us! So no matter where you look, you see a "part of that point" from 15 billion years ago.

    OK, this is an oversimplification as the universe was opaque for some time after the big bang, but you get the idea. Here's a potentially useful (though not perfectly accurate) analogy. Go inside a large spherical room with white walls. Put a bright light bulb at the center (big-bang). The walls are evenly illuminated because no matter which way you look, your line of sight intersects with some of the rays of the bulb, that seem to come to you from all around you.

    In fact, if you had a good enough detector, you could determine the shape of the bulb's filament by irregularities in the light from the walls. This is what the cosmic background explorer (COBE) missions are about.

    BTW, yes IAAP (I am a physicist).

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    #include "humorous_pop_culture_reference.h"