I have heard we have only mapped about 2% of the sky...amazing.

Can someone a little more enlightened on the subject explain something to me? How come there's that shape in the center that kinda looks like it's where the big bang occured? Is that it? or simple perspective distortion caused by our position in the universe?

>> ^EMPIRE:

Can someone a little more enlightened on the subject explain something to me? How come there's that shape in the center that kinda looks like it's where the big bang occured? Is that it? or simple perspective distortion caused by our position in the universe?


It is because stars in the foreground obscure things in the background. You have to look at the same peace of sky for thousands of years to get behind some of that clutter...some being entire galaxies

It is like watching cars in traffic, the bus that is sitting right in front of you blocks much of your field.

So the center from which all the galaxies seem to irradiate in that picture, is actually our location?


>> ^GeeSussFreeK:

>> ^EMPIRE:
Can someone a little more enlightened on the subject explain something to me? How come there's that shape in the center that kinda looks like it's where the big bang occured? Is that it? or simple perspective distortion caused by our position in the universe?

It is because stars in the foreground obscure things in the background. You have to look at the same peace of sky for thousands of years to get behind some of that clutter...some being entire galaxies
It is like watching cars in traffic, the bus that is sitting right in front of you blocks much of your field.

Yes. Technically, there is no center of the universe. The idea of "center" requires absolute space. Space and motion, as far as it concerns human observation, is relative. Space is also expanding, and it is unknown if the expansion is uniform. Meaning if there was absolute space, it would be very hard to detect what was unit 1 of space. The background radiation used to detect the existence of the big bang is mostly uniform, so you can't try and find a true center from that either. Don't think of the universe as expanding from a single point, think of it as reality expanding and incorporating more space.>> ^EMPIRE:

So the center from which all the galaxies seem to irradiate in that picture, is actually our location?

Every point is the center of the universe.

Thank you for the explanation.

I am the center of my universe.

You are the center of yours.

I'm going to remember all these one liners about the center of the universe to impress my friends next time we smoke pot.

Also, the two areas of black are caused by all of the clouds of dust within our own galaxy that we cannot see past.

>> ^Fusionaut:

Every point is the center of the universe.


I have heard that before, though I was always left with a profound since of want in explanation. I understand that since we live in a system where position is only known by relative surroundings, that center can be applied very liberally to any and all points as they all have unique reference points to themselves as the center. But that is more actuality described as the identity principle, a wholly different idea. As for my interpretation, one point can reference every other point in the universe system, and as a result, create a near infinite amount of central points. Meaning center, in a relative since, doesn't exist in they way we actually mean center. Objective center doesn't exist in other words. Perhaps we are saying the same thing though?

[redacted]

I am not sure what you mean by Pre-inflation exactly. If you mean when the universe was a singularity I would argue that concepts of center do not apply to objects that do not have dimension. More to the point, there was no space when there was just a singularity, a concept of center needs space, it is a quality of center.

I like your analogy, but I don't know if that works in our case. The problem lays in space itself, it has no markers or identifiers. A single unit of space is no different than any other, it is also impossible to know if something is space, or not space. The only thing that is possible to know is the distance that exists between objects in space. Relativity tells us that no observer has the authority to say anything about rest or motion objectively, they are both trapped in subjective prisons. As a result, there is no way to know if something is moving away from a position in space, you can only know if it is moving away from something else. That is the problem with objective space, as far as it concerns humans, there is no such things, so talk about a center of space is meaningless to us. We can only understand objects in space relative to other objects in space, not about space itself.

That is my take on it though, I am not sure I completely understand how relativity is supposed to work in space/time when concerning absolute space. As far as I know, there is not such thing as absolute space in relativity.

>> ^Mcboinkens:


I disagree. Pre-inflation there was a center, and therefore post-inflation must also have a center. Not being able to observe of calculate that center is another story.

Here's my anology: if you took a blob of water(floating, you'll see why in a second), you would have a center in that blob. Add enough heat to vaporize it into a steam cloud instantaneously, and you have a more expansive form of water. However, there is still a center, since it the molecules spread out evenly in all directions(obviously this doesn't happen in the real world but work with me here). Now imagine this cloud is diffusing throughout the room, but the room has no physical limit. It has infinite volume. It may spread unevenly, but logic(and physics) dictates it will tend to spread in all direction. It is expanding still, yet it would still have a center, which was where the blob was initially or close to it.. However, if we just began to observe this steam at the time where it was already spreading throughout the room, we would have no idea where that center was, because it all looks the same density and structure-wise.
Just my thoughts on the subject.

Check out http://www.atlasoftheuniverse.com/universe.html . According to this site there are 3.0 * 10^22 stars in the visible universe and it goes on to say "The geometry of the universe suggests that it may have an infinite size and that it will expand forever. Even if the universe is not infinite, our visible universe must be a minute speck in a much larger totality."

Most of those empty spaces between the wings filled with galaxy clusters are places that haven't been mapped by this project yet.

About there being a center of the universe you could say we are at the center of our observable universe, this is because we can only see up to the places where light has been coming from (actually 46 billion ly in all directions).

However imagine a star system 15 billion light years away from us, they can also so a sphere with a radius of 46bly. This means that they can look 15 billion light years into a direction we cannot see. Furthermore this means we have no idea of how big the actual universe it. It could be tens of times bigger than we see, 10^10 times bigger, or infinite. The center of the real universe must be at the big bang so in a sense everywhere is the center because from out the big bang everything was inflated from nothing into everything. This inflation because it was faster than light has led us to be unconnected with the universe beyond 46bly.

Mind boggling cannot describe the awesomeness and ungraspability of the whole universe.

*promote

Promoting this video back to the front page; last published Thursday, December 9th, 2010 10:55am PST - promote requested by cybrbeast.

>> ^cybrbeast:

About there being a center of the universe you could say we are at the center of our observable universe, this is because we can only see up to the places where light has been coming from (actually 46 billion ly in all directions).
However imagine a star system 15 billion light years away from us, they can also so a sphere with a radius of 46bly. This means that they can look 15 billion light years into a direction we cannot see. Furthermore this means we have no idea of how big the actual universe it.


Acutally, we're pretty lucky to have evolved when we evolved. If the universe is flat and will expand forever, there will be a time when creatures evolve when space has expanded that much, that they can't see other galaxies. What a twisted and creature-centric world view they must derive from that observation...

It's a big and uncaring universe out there.

@srd, if expansion continues to speed up there will come a time where we cannot even see neighboring stars. However, we are talking about extreme timespans here, many times the current age of the universe.

Indeed. The universe is playing the very, very long game.

...so how about that weather?

[redacted]

I see 0.0 space has the usual pockets of red. Better make sure your clone is up to date.

The two pie-shaped black bands reaching from the center to the top/bottom of the image respectively are shadows of our galactic center. These areas at present can not be mapped, as there is simply too much garbage at the center of our galaxy to see past.

As soon as we can figure out how to image past black holes....or we can get a camera with a different perspective on the universe (say...place it in a different section of our galaxy or outside our galaxy entirely), then we can map these areas.

>> ^ChairfaceChippendale:

I see 0.0 space has the usual pockets of red. Better make sure your clone is up to date.


Heheh nice Eve reverence.