Where does SPACE END? By that I mean, does it curve back unto itself, go on forever, or does a wall exist that prevents us from seeing/travelling any further,,BTW, how far has the HST seen an object, in miles, light years and cosmic years..... Oh yeah, what was here BEFORE the BIG BANG?

Hi Carl

First of all go check out Prof. Edward Wright's web-site. He covers all your questions or has links to sites that can answer them.

http://www.astro.ucla.edu/~wright/intro.html - Intro page... but you will find more specific answers at his Cosmology tutorial...

http://www.astro.ucla.edu/~wright/cosmolog.htm

Now as for space's end... well it depends on its shape and so far as we can tell it might be finite or infinite. If finite it could be a number of hyperspatial shapes, the simplest being a hypersphere. A 3-sphere [say a regular globe] has no end if you travel along its surface. Similarly a 4-sphere's 3-volume [analogous to the sphere's surface] has no edge.

If the Universe is infinite then there is no end. Except it all converges back to a point in finite time - hence the Big Bang is the pointy end of space-time.

More exotic models for the Big Bang do exist and they have analogies to walls and shockwaves but they are currently beyond view. Light hasn't travelled far enough or for long enough to be seen from the edge of space yet.

Now the HST isn't the telescope to see furtherest. The most distance bit of the Universe we can see is the Cosmic Microwave Background at a red-shift of about 1000. Using the equations from Ned's tutorial that's about 95 billion light years away and about 13.5 billion years behind us in time.

http://www.astro.ucla.edu/~wright/cosmo_02.htm#MD ...distances in cosmology

Before the Big Bang? Well in a very real sense we might not be able to see beyond the tiny fraction of a second because of the way the matter-energy of the Universe smoothed out and then slightly wrinkled up as it was created by the expanding Universe - this might've destroyed forever any hint of what happened "before".