Calling all Doper astronomers!
The title is the headline of a story on CNN tonight, and the story has to do with the next generation of terrestrial telescopes, that will, according to the story, come on line in the next 10-15 years. Here’s the url: http://www.cnn.com/2009/TECH/space/08/18/new.generation.telescopes/index.html
My question is how “soon” after the Big Bang can we image?
The headline implies we have some sense of the location that all the observable universe is moving away from, which is the ostensibly site of the Big Bang. Is that the conventional wisdom of current astronomy?
As interesting is to me is the question of whether we can see anything at the location of the Big Bang younger than the distance the Earth is away from that presumed location, which the headline implies, and the story doesn’t contradict.
How far is Earth away from the supposed location in light-years? Can we see anything temporally closer to the Big Bang than that? Or is this just a really bad headline?
The only number the article mentions is a few hundred million years, sounfortunately doesnt seem nearly as close to the beginning as an earth distance. I wonder if that will ever be possible?
The universe became translucent roughly 380,000 years after the Big Bang, so that’s the furthest back one can ‘see’. However, the photons emitted back then have been redshifted far out of the visible spectrum, and are now observable in the form of the so-called cosmic microwave background. I don’t know how far one could see ‘back in time’ using optical telescopes.
As for the ‘location’ of the Big Bang, well, you’re standing on it, and so am I – there’s really no good sense to the concept; after all, if it was the event that created space, how could it have taken place anywhere within space? In a way, the Big Bang happened everywhere, and, if you look at the sky, all (or almost all) galaxies are in fact ‘moving away’ from us; however, that doesn’t make us special, since observers in other galaxies would see the same picture. The ‘inflating balloon’-analogy works well here: picture a balloon with some little galaxies painted on it; if you inflate it, all the galaxies will move away from each other (like this – YouTube link). If you ‘reverse time’ and imagine it deflating and contracting to a point, you see that while once all the matter in the universe was in one single point, that point wasn’t anywhere in space, but all of space, in a sense.