Hubble Deeper Field

[Hexxenhammer]

No one has started a thread about the new Hubble pictures, so here we go. (http://www.nasa.gov/images/content/56533main_MM_image_feature_142_jwfull.jpg)

To think that you can look at a tiny blank spot of sky and find that it contains 10,000 galaxies and that you're looking back in time up to 13 billion years is mind boggling. I can barely wrap my mind around it. When I was little I would lay in bed awake, trying to comprehend infinity. I'm still trying.

[No Answers]

I'm using the shot as my desktop.

This sort of thing, I've always found quixotic to the extreme... ancient beauty.

There will maybe be better pics in 2011. Can't wait!

[Sundog]

Hubble thrust his huge Deep-Field Probe challengingly at the universe.

"Deeper," the universe said urgently. "Deeper..."

[No Answers]

Originally posted by Sundog
Hubble thrust his huge Deep-Field Probe challengingly at the universe.

"Deeper," the universe said urgently. "Deeper..."

This post is in violation of the "Keep a Civil Tongue" rule, and is in unacceptable poor taste. A mis-behavior of this sort is a set back for the JREF educational mission, and therefore has no place in this forum.

This is a warning that any further violation of the said rule may result in suspension or permanent banning from the JREF forums.

[Eos of the Eons]

Hey! I watched all that on the Discovery Channel last night. They said they were going back almost 13 Billion years there. The estimated age of the universe is around there (speaking solely from memory of the program), and they expect that is the oldest shot of the universe yet. They speculated how this is looking back in time to where the light is from when the universe was rather brand new.

What if they are able to get a shot going back 15 Billion years? What if there is no end at all to the universe and galaxies just go on forever? I highly support that idea.

I'm just excited to see that there is no visual end of galaxies and matter of the universe as of yet.


Very Beautiful picture, thank you.

[wollery]

It is the picture that goes the furthest back in visible light. The data from COBE, BOOMERANG, WMAP and all the other Cosmic Microwave Background probes image light from the surface of last scattering, 379,000 years after the Big Bang. That was when the Universe was in its' infancy.

[Yahweh]

13 Billion Years? Hahahahaa! I'd guesstimate not much older than 5 or 6 thousand years HAHAHAAaaa:D:D:D:p

[Cecil]

Originally posted by wollery
It is the picture that goes the furthest back in visible light. IIRC, at a distance of 13Gly, the visible light is almost completely shifited into the infrared.

Edited to add: more info at http://www.randi.org/vbulletin/showthread.php?s=&threadid=36777&highlight=hubble

[Fidelio]

Originally posted by Hexxenhammer
No one has started a thread about the new Hubble pictures, so here we go. (http://www.nasa.gov/images/content/56533main_MM_image_feature_142_jwfull.jpg)

Not wishing to be too much of a pedant here but...ahem...

http://www.randi.org/vbulletin/showthread.php?s=&threadid=36777]

And yes it is awesome, I downloaded the full version and will be perusing it for a few months.

[Garrette]

Silly questions from a non-scientist provoked by these images.
Perhaps someone can recommend books or sites for laymen.

When I saw these images (on BBC first) along with the commentary about their age, I was, like most people I think, awed. It truly amazes me.

Then I got to thinking that my simple perception of how we're "looking back" is mistaken.

I--and most laymen, I think--consider these to be photos of something actually far away, i.e., our vision extends across the trillions of light years to see what 'is;' Hubble merely extends the distance we are visually traversing by picking up light that is physically far away. (I've said this poorly, but I think you get the gist).

But the latest images drove it home that what Hubble really does is gather light that is already here and converts it into an image. Actually, it gathers light over an extended time so that it is in fact recording a 'stream' of light or of photons and recording them over each other to increase their visibility. (Poor word, again, sorry).

So really, we see nothing at a distance. We are localized, registering light as it reaches us and merely interpreting data to 'mean' distance.

Further, over long distances, the interpretation becomes one of time.

Which leads to all sorts of philosophical questions that have undoubtedly been hashed and rehashed by smarter people than I am.

So where can I find those hashes that will allow me to make sense of this?

Sorry for the lack of clarity; I can't figure out how to say it better.

[Oleron]

Originally posted by Hexxenhammer
No one has started a thread about the new Hubble pictures, so here we go. (http://www.nasa.gov/images/content/56533main_MM_image_feature_142_jwfull.jpg)

To think that you can look at a tiny blank spot of sky and find that it contains 10,000 galaxies and that you're looking back in time up to 13 billion years is mind boggling. I can barely wrap my mind around it. When I was little I would lay in bed awake, trying to comprehend infinity. I'm still trying.

It's amazing to think we're looking back in time over 6000 years!

I think I can see Jebus's face in the galaxy, bottom right.

[slimshady2357]

Originally posted by Fidelio


Not wishing to be too much of a pedant here but...ahem...

http://www.randi.org/vbulletin/showthread.php?s=&threadid=36777]

And yes it is awesome, I downloaded the full version and will be perusing it for a few months.

I d/l the full version too, how would I view it easily? It's a 60 meg jpg that is 6200 X 6200!

Are there programs that I could get that would make viewing it and 'moving around and zooming in' possible?

It's HUGE! :D

Adam

[Captain Trips]

Originally posted by Garrette
... I got to thinking that my simple perception of how we're "looking back" is mistaken.

I--and most laymen, I think--consider these to be photos of something actually far away, i.e., our vision extends across the trillions of light years to see what 'is;' Hubble merely extends the distance we are visually traversing by picking up light that is physically far away. (I've said this poorly, but I think you get the gist).

But the latest images drove it home that what Hubble really does is gather light that is already here and converts it into an image. Actually, it gathers light over an extended time so that it is in fact recording a 'stream' of light or of photons and recording them over each other to increase their visibility. (Poor word, again, sorry).

So really, we see nothing at a distance. We are localized, registering light as it reaches us and merely interpreting data to 'mean' distance.

Further, over long distances, the interpretation becomes one of time.

I'll take a stab at this. We aren't actually seeing light that is "physically far away." The light we are seeing is composed of photons that are here now. However, those photons have traveled 13 billion light years, which means that they have been traveling for 13 billion years (since a light year is the distance light travels in a year.)
Now, since the photons have been traveling all that time, what we are seeing are photons that were emitted by those galaxies at that time. Therefore, what we are seeing is how those galaxies were, that long ago. To see them as they look "now", we would have to wait for the light to get here from there, which would take another 13 billion years. (Sorry, but that is past my bedtime.)

Is that clearer? I admit that what I have said isn't the most rigorous of scientific explanations, but it should be okay in, as you would put it, layman's terms.

(I won't go into the relativistic definition of "now". It would only confuse this issue.)

[Garrette]

Thanks, Captain Trips, for the attempt, but I don't think I communicated clearly what I'm after.

I understand we're seeing photons now that are conveying 13 billion year old information. But that's the cause of my confusion, not the answer to it.

I think I need an Einstein Primer, really. Here's why:

1. I'm seeing photons that are here now but which are conveying 13 billion year old information.

2. Simultaneously, I'm seeing photons from my computer screen which are conveying current information (discounting the tiny amount of time it takes for the photon to travel from the screen to my eyes).

3. I am simultaneously see old and new information.

So I'm simultaneously experiencing two times.

But the reason I'm doing that has nothing to do with time but with distance.

So distance is time.

Which means I'm a genius like Einstein because I'm figuring this out all on my own. {If only I could do math, I'd be famous, too}

I've actually had an academic awareness of this little problem (to me, anyway) for some time, but it was only the latest Hubble image that made it visceral.

Other than submitting to the urge to retreat into neverending rounds of rum-and-coke, how do I come to grips with this?

As always, the answer is apparently: read and study.

I hate that...

[FireGarden]

Captain Trips
To see them as they look "now", we would have to wait for the light to get here from there, which would take another 13 billion years.
It may take longer than that. The galaxy is further away from us now! How much further away, compared to 13 billion LY?

Eos of the Eons
What if they are able to get a shot going back 15 Billion years? What if there is no end at all to the universe and galaxies just go on forever? I highly support that idea.
As you look further back in time, eventually all you'll see is the microwave background which marks the moment when the universe became transparent. That's already been mapped by COBE, as wollery has already said.

But as for the universe going on forever...
It does, at least, go on beyond what's visible. IE: there are, surely, plenty of galaxies more than 13 billion light years from here. It will be a very long time before anyone in this part of space gets to see them. In fact, the universe may be so big that the expansion will move apart some points more quickly than the speed of light.

In fact I'm not sure if we would ever see galaxies that are not currently in the visible universe. If the universe became transparent 15 billion years ago (say), and there is a galaxy now 16 billion LY away, then how would we ever see it?

Garrette
As always, the answer is apparently: read and study.

I hate that...

I hate that you hate that! :)
If you find the subject interesting, then how can studying it be a chore? And would it be as interesting if it wasn't as complicated? After all, if it could be learnt in a second it can be forgotten in a second.

[Eos of the Eons]

So really, we see nothing at a distance. We are localized, registering light as it reaches us and merely interpreting data to 'mean' distance.

Very true, but that light we are receiving is that old, and has travelled a long long time from far far away.

Originally posted by FireGarden


As you look further back in time, eventually all you'll see is the microwave background which marks the moment when the universe became transparent. That's already been mapped by COBE, as wollery has already said.

But as for the universe going on forever...
It does, at least, go on beyond what's visible. IE: there are, surely, plenty of galaxies more than 13 billion light years from here. It will be a very long time before anyone in this part of space gets to see them. In fact, the universe may be so big that the expansion will move apart some points more quickly than the speed of light.

In fact I'm not sure if we would ever see galaxies that are not currently in the visible universe. If the universe became transparent 15 billion years ago (say), and there is a galaxy now 16 billion LY away, then how would we ever see it?


.

So what if we just keeping seeing light from farther away distances and never seen an ending to incoming light? There should a point at which light no longer comes from if the universe 'ends' at its beginning right? What if we never see an end? What if we receive light from galaxies that are over 16 billion years old? Or 18, or 20?

[FireGarden]

Originally posted by Eos of the Eons

So what if we just keeping seeing light from farther away distances and never seen an ending to incoming light? There should a point at which light no longer comes from if the universe 'ends' at its beginning right? What if we never see an end? What if we receive light from galaxies that are over 16 billion years old? Or 18, or 20?
If the universe is infinitely old, then what happens if you run the expansion in reverse?

Remember, it's not just galaxies flying apart. It's the actual space getting bigger.

Then there's the cosmic background radiation. How do you explain its similarity in all directions if all those points weren't once close enough to interact?

We may be wrong about the timescale, but can we be wrong that there was a beginning?

[Eos of the Eons]

Originally posted by FireGarden

If the universe is infinitely old, then what happens if you run the expansion in reverse?

Remember, it's not just galaxies flying apart. It's the actual space getting bigger.

Then there's the cosmic background radiation. How do you explain its similarity in all directions if all those points weren't once close enough to interact?

We may be wrong about the timescale, but can we be wrong that there was a beginning?

I heard some galaxies are actually moving closer to ours, but some further away from ours. I just don't understand how this can happen if we are infinitely expanding 'outwards'.

In my infinite ignorance, I have no idea what cosmic background radiation is. I have something to look up now, and hopefully that will explain a few things, thank you. Can you expand on that topic?

If there was one beginning, then why can't there be several?

Another bit of my ignorance that I hope someone can explain in layman's terms is how we know for sure that "actual space" is getting bigger, and explain what exactly is this "space" that can get bigger if space is essentially nothing. Is the universe getting bigger, or all of space?

Then one of these I may start knowing what the heck I am talking about :)


For instance, I have no idea what this means:

By the early 1970's it became clear that the CMB sky is hotter in one direction and cooler in the opposite direction, with the temperature difference being a few mK (or about 0.1% of the overall temperature). The pattern of this temperature variation on the sky is known as a "dipole", and is exactly what is expected if we are moving through the background radiation at high speed in the direction of the hot part. The inference is that our entire local group of galaxies is moving in a particular direction at about 600 km/s. In the direction we are moving the wavelengths of the radiation are squashed together (a blue-shift), making the sky appear hotter there, while in the opposite direction the wavelengths are stretched out (redshift), making the sky appear colder there. When this dipole pattern, due to our motion, is removed, the CMB sky appears incredibly isotropic. Further investigations, including more recent ones by the COBE satellite (eg Smoot et. al.), confirmed the virtual isotropy of the CMB to better than one part in ten-thousand.
http://www.astro.ubc.ca/people/scott/cmb_intro.html

I am extremely curious about all this. I would love to understand it all more.

[Oleron]

Eos,

Have a read of George Smoot's book 'Wrinkles in Time'. It describes the investigation of the cosmic background radiation and is a fascinating insight into modern astronomy.
It is easy to read and as gripping as a detective story, IMO. It will answer all your questions.

[Archon1]

This probably won't make much sense, but here goes anyway. I've been confusing myself with this for about two weeks now.

If all matter in the universe stared at one point in space. How could we see back in time 13 billion years if it took us that amount of time to get where we are now? Does this suggest that the universe is a lot older than 13 billion years? Are we flying through the universe at nearly the speed of light, or am I missing something very simple here?

[wollery]

There are several posts in this thread that I think I need to respond to , but I'll start here.

Originally posted by FireGarden
But as for the universe going on forever...
It does, at least, go on beyond what's visible. IE: there are, surely, plenty of galaxies more than 13 billion light years from here. It will be a very long time before anyone in this part of space gets to see them. In fact, the universe may be so big that the expansion will move apart some points more quickly than the speed of light.No two objects in the Universe, no matter how far apart they are, can move relative to each other at a velocity greater than the speed of light. Einstein's theory of special relativity excludes this possibility.

In fact I'm not sure if we would ever see galaxies that are not currently in the visible universe. If the universe became transparent 15 billion years ago (say), and there is a galaxy now 16 billion LY away, then how would we ever see it? The size of the visible Universe expands as the Universe itself gets older. If we were to measure the distances to the furthest galaxies as they are at this time then many of them would be more than 13 billion light years away. However, they are not beyond the edge of the visible Universe. You have to remember that the edge of the visible Universe is less than a billion years old. The light being emitted by a 13 billion year old galaxy that's 16 billion light years away won't reach us for another 25 billion years or so! By which time the Sun and the Earth will be long gone.

[CurtC]

Eos wrote:
I heard some galaxies are actually moving closer to ours, but some further away from ours. I just don't understand how this can happen if we are infinitely expanding 'outwards'.If a friend is driving over to your house, he is getting closer to you. This doesn't violate the idea that, on a large scale, things in the universe are getting farther apart. There are also stars in our galaxy that are getting closer to us. And there are nearby galaxies that are getting closer to us, because we're gravitationally attracted to each other, or both to the same thing. The expansion of space applies at even larger scales. When you get far enough away that local gravitational attractions don't override it, things will be moving away from us, and the farther, the faster.In my infinite ignorance, I have no idea what cosmic background radiation is.Just to get you started, right after the Big Bang, the universe was too hot to allow light to propagate. After it was 300000 years old, it had cooled enough to allow photons to pass through. Some of these photons have been travelling that whole 13.7 billion years, and are just now arriving to where we are. And what's more amazing - they're coming pretty much equally from all directions. This faint glow is called the cosmic background radiation, sometimes the cosmic microwave background, since the energy of the photons has been shifted down by the expansion of space into the microwave region (as opposed to the visible light region) of the light spectrum.

[wollery]

Originally posted by Eos of the Eons
I heard some galaxies are actually moving closer to ours, but some further away from ours. I just don't understand how this can happen if we are infinitely expanding 'outwards'. The vast majority of galaxies are moving away from us, but the galaxies in the Local Group (such as M31, the Andromeda Galaxy) are gravitationally bound to each other. This means that some of the Local Group galaxies are moving (sort of) away from us and some are moving (sort of) towards us. What's actually happening is that all of the Local Group galaxies are orbiting the centre of mass of the group. However, the distances and velocities involved mean that we can't actually measure the tangential velocities of the other galaxies, only their radial velocities.

In my infinite ignorance, I have no idea what cosmic background radiation is. I have something to look up now, and hopefully that will explain a few things, thank you. Can you expand on that topic?Put simply, the cosmic microwave background (CMB) is the afterglow of the big bang. It is a constant, almost invariant "glow" equivalent to a temperature of ~3 Kelvin.

If there was one beginning, then why can't there be several?There can, some theories have a repetitive Big Bang, Big Crunch, others have multiple universes. We don't know, and probably never will.

Another bit of my ignorance that I hope someone can explain in layman's terms is how we know for sure that "actual space" is getting bigger, and explain what exactly is this "space" that can get bigger if space is essentially nothing. Is the universe getting bigger, or all of space?First off the Universe is all of space!
The first clue to the expansion of the Universe came from Einsteins' relativity, the simplest solutions of which require the Universe to be either expanding or contracting. Hubble then discovered that almost all of the galaxies were moving away from us, and that the speed of their motion was proportional to their distance away from us, confirming relativities prediction. The clincher though was the CMB, this is also a prediction of relativity, and (so far as we know) can only come from a Big Bang.

Then one of these I may start knowing what the heck I am talking about :)

For instance, I have no idea what this means:

quote:
By the early 1970's it became clear that the CMB sky is hotter in one direction and cooler in the opposite direction, with the temperature difference being a few mK (or about 0.1% of the overall temperature). The pattern of this temperature variation on the sky is known as a "dipole", and is exactly what is expected if we are moving through the background radiation at high speed in the direction of the hot part. The inference is that our entire local group of galaxies is moving in a particular direction at about 600 km/s. In the direction we are moving the wavelengths of the radiation are squashed together (a blue-shift), making the sky appear hotter there, while in the opposite direction the wavelengths are stretched out (redshift), making the sky appear colder there. When this dipole pattern, due to our motion, is removed, the CMB sky appears incredibly isotropic. Further investigations, including more recent ones by the COBE satellite (eg Smoot et. al.), confirmed the virtual isotropy of the CMB to better than one part in ten-thousand.

http://www.astro.ubc.ca/people/scott/cmb_intro.html

I am extremely curious about all this. I would love to understand it all more. What part(s) of that don't you understand? I'm happy to help if you can be a bit more specific.

[FireGarden]

wollery
This page http://curious.astro.cornell.edu/question.php?number=575 backs up the idea that objects can seperate at the speed of light. IE: the distance between them increases more quickly than c. That increase is due to expansion of space not actual movement.
If we were to measure the distances to the furthest galaxies as they are at this time then many of them would be more than 13 billion light years away. However, they are not beyond the edge of the visible Universe.
Yes, to the first sentence.
I had greatly underestimated what expansion could achieve in the time since the visible galaxies emitted the light we are seeing.

But "No" to the second.
I've already given my explanation, based on the above link, in the "observable universe" thread. As we watch distant galaxies they will appear to slow down and stop (become infinitely redshifted). In fact, they will have continued to have had active lives, but that existence will take place outside the visible universe, which expands - but not quickly enough to retain every object that's currently visible. That's due to recesion at speeds greater than the speed of light.

When we see today's CBR, we see light emitted from a point X that was quite close to us about 13.7 billion years ago. But expansion of space has put that point so far away from us that we cannot see anything that happened at that location after today's CBR was emitted. Tomorrow's CBR comes from a point that, 13.7 billion years ago, was just a little bit further away than X. The visible universe expands only in the sense of seeing further into space as it existed 13.7 billion years ago.

At least, that's what I understand from the above link. (I've had to retract a few things that I posted on this subject since reading that link)

Eos of the Eons
CurtC has explained CBR for us, and he and wollery pointed out that the local group of galaxies (like Andromeda) are gravitionally bound.

The common analogy for expansion is to think of a balloon as it is inflated. If there are two marks painted on the balloon, then those marks cannot move through the surface of the balloon - their positions are fixed. But they can move apart from each other, and for a given rate of inflation, you can get the marks to seperate at any speed if you can get them far enough apart. Even at speeds greater than that of light.

When Einstein first formutlated his General theory of relativity, he came up with a formula that implied the expansion of space. But he thought that that was absurd, so he added a term to cancel it out. He called that his biggest blunder. He could have predicted the expansion.

I don't understand the derivation of that formula, so I'll stop here! (Until I'm better informed, anyway! Ask me in a couple of years! :))
If there was one beginning, then why can't there be several?
There may have been more than one, but we are observing the consequences of only one.

The point of my previous post was to give you a couple of things (expansion and CBR) that would need to be explained by any cosmological theory. After all, these are observed phenomena.

[FireGarden]

I thought I would highlight this since espritch has already addressed it in the other thread.
and explain what exactly is this "space" that can get bigger if space is essentially nothing.
espritch's reply:
Space is not "nothing". According to relativity, it can be curved by gravity and it can expand (spreading out the matter of the universe in the process). According to quantum mechanics, it is full of zero point energy that is constantly producing and destroying sub atomic virtual particles. Whatever space is, it is certainly not nothing.



I would add that spacetime is the place where events happen.
In the past, spacetime was so small that events could only be seperated by fractions of a second or by fractions of a metre. It's grown since then!