Where Is the Center of the Universe? (Ask an Astronomer)

[atista007]

Everything has a center, now go back to the lab and tell me where the god damn center is

[CBALLEN]

How did all the gases come together to make galaxies if all things were moving away from each other at the speed of light,or faster, in this giant expansion?Gases don't produce gravity only solid bodies do,so that destroys that.

[CBALLEN]

Even with a balloon it still has a center in the center of the balloon,a ball has a center within th ball,a golf ball has a center no matter how many layers are put on it.Dose not a circle have a center? We make a circle with a compass.

[randy95023]

I'm probably making a rookie mistake in logic, but... If everything "blasted" away from a singularity in the Big Bang, and the Universe is still expanding at high speed, HOW can Galaxies collide with one another at right angles?? I'm obviously a Layman asking a simple question. Can someone please answer?

Thanks, Randy

[Xellith]

@randy95023 As far as I understand it - gravity has pretty much thrown everything around everything else. An example of this would be stars flying around the galactic center, planets flying around. Galaxies even orbit each other. I believe the Milky Way has 5 dwarf galaxies near/in it atm. Someone feel free to correct me if I'm wrong. Id rather be pointed out wrong than someone get some inaccurate information.

[randy95023]

@Xellith Thanks! That's pretty much what my answer would be, but still "Expansion" shows that all Galaxies are flying away from each other yet paradoxically Galaxies are constantly colliding. That's a sheer contradiction! I think you are right about Gravity's effect, yet Astronomers all say that Galaxies are all flying away from each other. Can BOTH of these observations be correct? Hmmm...

[bandet888]

I am the center of the universe! LOL just kidding.

[bandet888]

How do we really know all the galaxies are moving further away. Do they actualy look smaller and smaller the next time we see it or is it because the further galaxies are more red indicating a light dopler effect indicating they're moving away? Maybe the frequency of light just changes after traveling a long distant. I'm not a scientist I'm just wondering. You'll have to excuse me if my comment seems dumb.

[GeorgeNada1]

then why do galaxys collide if everything if moving away from one another?

[TheGlassDot]

@GeorgeNada1 Gravitational pull overcomes the pull of expansion.

Now, you might wonder, why didn't gravity take over right away?

Well, think of an example like this: When you roll a ball up an incline, your initial push overcomes gravity for a period of time. Then gravity overcomes the force of your push, and pulls the ball back down. This would be our example for two galaxies first expanding, and then colliding. But, why does this not happen for every galaxy? (contin....)

[TheGlassDot]

@GeorgeNada1 (contin...) First, you must understand that if The Big Bang is true, it's not as if it would have sprouted fully formed galaxies like a cat giving birth. And, certainly not every galaxy would form at the same time. So, some galaxies would form over time far enough away from others that they are not caught in the each other's gravitational pull, and continue in the direction they were moving. Others would develop too closely to escape eachother--like our galaxy.

[TheRichardJudy]

What force in the expanding universe is causing the galaxies to move? Is everything moving at the Same speed relative to the expanding universe?

[gilbertpinson]

The whole explanation is also based on the assumption that a big bang created all matter and space, and that's just a theory. For all we know there was matter and space long before the big bang, just not in this universe. Or maybe there wasn't even a 'big bang' to begin with. Prove to me infalliably that there was and then we'll talk.

[GeorgeNada1]

@gilbertpinson i know right.. if there was a 'big bang' then it seems like they could find where it started.. and then why would galaxys collide if all space time is moving away from everthing... if its like the vid says then every 'point' IS the center of the universe, which only creates another paradox...

[TheGlassDot]

@gilbertpinson Actually, it isn't based on an assumption of a big bang. It's based on red shift and blue shift.

For example, when someone blowing their horn passes you on the street, as it approaches the pitch is higher, and as it goes away from you the pitch is lower. In actuality, the pitch is constant, but to our perception, the pitch is changing. The same happens with light. As something moves away from us, we perceive an increase in wavelength--we call this red shift. Check wiki for more.

[gilbertpinson]

In all of those examples there is a centre. You're just assuming the universe is a disc instead of a sphere. In the balloon example, all the 'galaxies' are spreading away from each other, but they are also all equally spreading away from the centre of the balloon, where the air is pushing it out. I know it might not work like that in the universe, but the logic of the explanation is flawed.

[TheGlassDot]

@gilbertpinson The balloon example is only a way to show how galaxies moving away from all other galaxies at the same time may look. Because, to some it is quite a mind trick to imagine everything moving away from everything else.

The balloon example is not an accurate model, because scientists are quite sure that the universe is a "flat" universe. For more on that you can watch this lecture: watch?v=7ImvlS8PLIo

[TheFrostflower]

so what's at the edge of the universe?

[SuzLa1]

Strange how everything came from a small point in space and all laws of physics break down when thinking of before the big bang. 

[ALLAHALLAHism]

FUCK MY MIND IS FRIED!

[bot06]

To explain it more. Consider a ballon near the edge for example. That ballon is moving outward perhaps. The ballon which is next to it is also expanding and moving away, but in which direction? Well the answer is this is not explosion but expansion. To visualize it more. Consider a box full of small balls. Now consider you expand the box 4 times and all balls inside *expand* in the box. There is no center because the expansion is uniform. All balls simply moved away from each other.

[bot06]

The 3D model is like this. You enter your bedroom and you see there are 100 balloons in the room. All of a sudden every balloon move away from each other. Now here it is a bit tricky part. The balloon do not move away as if moving away from a center. Each ballon moves away from the other balloon as if that ballon is the center. Since there are 100 balloons and each moving away from each other in *all* directions, the whole fabric in 3D is expanding.

[bot06]

Ok one explanation is this. Let say you enter your living room and you see a carpet. On the carpet there are 10 pillows. All of sudden these 10 pillows move away from each other. There is no center, they just start to move away from each other. But when yo u think of 3D, thinks become more complicated. Now I will explain it like this.

[bot06]

Well the balloon does have a center so why not the universe. I think the universe had the center but now since the matter is expanding in each direction, we can't say where the center is. Perhaps we see only the part that is expanding in our direction. Our scopes will never get the light was was going in the other direction. But I still dont know.

[eightythreeab]

Yeah but the inside of the ball would be the center. No?

[MrRichardQED]

@MrShoeguy erm no, for example take the surface of a ball, thats finite, yet it has no center. Your argument doesnt make sense

[08Hellboy]

It's true.

[vesposito27]

Since the universe is actually 4 dimensional, the center is at a certain spot in time as well as space. Also, since spacetime itself is expanding, - and started as a singulaity, in another sense, all points in the universe are the center.

[Smonjirez]

Well, this pretty much settles it.

The universe has (at least) a 4th space-dimension.

[karlwashere123]

We take for granted the knowledge that you guys share with us. Thank you.

[Furmilo]

If a cluster of objects (galaxies) doesn't have a center then that means the cluster doesn't have limits where it ends. How does space of infinite galaxies support big bang theory?

[EmperorofCartoons]

@Furmilo Space does have an end though, at least observable space does. You look at the faintest detectable light source and you can estimate how long it has been since that light began traveling and then take that amount of time and see how far light could possibly travel in time and that is the age and size of the observable universe.

[nikgervae]

These analogies always fail. If the sidewalk is getting longer, it's getting longer relative to something. If the expansion of space is like a balloon, well, you can easily determine the center of the balloon. It's not on the surface of the balloon, but it's there.

[JKTProductionzIncNCo]

yes i agree wit u man jus beacue the "center" isnt in 3 dimennional space then it probably is on another dimmension whcihc we havnt figured out yet, or unless our universe is coexiting wit another universe in different dimmensions but i agree witu though probabl another 2 decades b4 they come 2 tht conclusio though

[Darkconis]

@JKTProductionzIncNCo The balloon example is the best example there is to give. There is no center because the universe is like a big sphere that's expanding outward.

[Darkconis]

@nikgervae Space doesn't encompass the inner of the balloon. Take the balloon's surface as space. That's why wormholes are theoretical possible. It would be like punching a hole from one side of the balloon to another. Then you would be traveling through space that wouldn't be there otherwise.

[izlude2]

hubbles law hmm? i guess that explains why the universe is larger than it is older?

(about 14 billion years old but over 100 trillion lightyears large)

[alexbballboy]

whats your point???

[robdee4]

light years are not a measure of time, but are a measure of distance. A light year is equal to how far light can travel inside a vacuum (space) in the span of a year (Julian); assuming no interference.

1 light year = 5,878,630,000,000 miles

[ShadowWolfFalls]

man, what a ball buster!

[Hexatyrant]

So we have measured this expansion between atleast two different galaxies apart from earth ?

And no galaxies have ever collided ??.

Or is everything shrinking ?

And why is this effect localised to each galaxy ?

[JKTProductionzIncNCo]

A1: yea we hav

A2: no galactic collisons r pretty common in the universe in fact our galaxy is going to collide with the andromeda galaxy 3-4 billion yrs from now

A3: wel thts an interesting proposition but sci. evidence suggests not

A4: cause theres no real center located thus each galaxy can be treated as the center and is relevant to it's own time and space in comparison to another

hope this helped

[smawshot]

@JKTProductionzIncNCo How does scientific evidence suggest we aren't shrinking within space?

[JKTProductionzIncNCo]

@smawshot because of red shift the further sumthing is the longer it takes for light to reach and thus the light paritcle wavelengths become longer pushing it to the red spectrum of light signaling tht it pretty far away

[smawshot]

@JKTProductionzIncNCo And if everything was moving away at such an exponential rate, we should expect that some are doing so faster than the light could ever reach us. But yet we are not losing sight of distant objects in space via naked eye or telescopes but rather finding things even further out. If this space was expanding, is there an explanation as to why it seems to be case only with distant objects aside from "maybe gravity"?

[EmperorofCartoons]

@smawshot Because if everything were shrinking there would either be no apparent movement (If everything were shrinking perfectly to scale.) or everything would appear to be getting closer (Thus causing light to blue-shift.). This very question was very hotly debated in Hubble's day before he discovered the red-shift.

The red-shift of light, however, confirms our universe is expanding.

[lauradfromnc]

I thought the waterboy's mama was the center of the universe.

[mark96701]

TOOOOOOO Cool. That my buddy from Highschool !!!!!!!!!!!! Hey Dr. i noticed you used the word Logical. Testiment to Start trek which we know is better than Star Wars.

[feelosodan]

o yeah the word logical ha totally derived from star trek.

dip tard

jk i love all but i thought that was silly

[CousinoMacul]

I find the balloon example to be the most helpful.