Long Ago and Far, Far Away… Hubble Discovers Most Distant Galaxy Yet!

by Tammy Plotner on January 26, 2011

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Hubble Ultra Deep Field - Part D

No Princess is sending holographic help messages. No Hans Solo is warming up a Millenium Falcon to jump into hyperdrive. We don’t even have a Death Star waiting around the corner. But, what we do have is evidence that astronomers have pushed the Hubble Space Telescope to its limits and have seen further back in time than ever before. “We are looking back through 96% of the life of the universe, and in so doing, we have found just one galaxy, but it is one, but it is a remarkable object. The universe was only 500 million years old at that time versus it now being thirteen thousand-seven hundred million years old. ” said Garth Illingworth, Ames Research Scientist. We know about the Hubble Ultra Deep Field, but we invite you to boldy go on…

While studying ultra-deep imaging data from the Hubble Space Telescope, an international group of astronomers have found what may be the most distant galaxy ever seen, about 13.2 billion light-years away. “Two years ago, a powerful new camera was put on Hubble, a camera which works in the infrared which we had never really good capability before, and we have now taken the deepest image of the universe ever using this camera in the infrared.” said Garth Illingworth, professor of astronomy and astrophysics at the University of California, Santa Cruz. “We’re getting back very close to the first galaxies, which we think formed around 200 to 300 million years after the Big Bang.” The study pushed the limits of Hubble’s capabilities, extending its reach back to about 480 million years after the Big Bang, when the universe was just 4 percent of its current age. The dim object, called UDFj-39546284, is a compact galaxy of blue stars that existed 480 million years after the Big Bang, only four percent of the universe’s current age. It is tiny. Over one hundred such mini-galaxies would be needed to make up our Milky Way.

The farthest and one of the very earliest galaxies ever seen in the universe appears as a faint red blob in this ultra-deep–field exposure taken with NASA's Hubble Space Telescope. This is the deepest infrared image taken of the universe. Based on the object's color, astronomers believe it is 13.2 billion light-years away. (Credit: NASA, ESA, G. Illingworth (University of California, Santa Cruz), R. Bouwens (University of California, Santa Cruz, and Leiden University), and the HUDF09 Team)

Illingworth and UCSC astronomer Rychard Bouwens (now at Leiden University in the Netherlands) led the study, which will be published in the January 27 issue of Nature. Using infrared data gathered by Hubble’s Wide Field Planetary Camera 3 (WFC3), they were able to see dramatic changes in galaxies over a period from about 480 to 650 million years after the Big Bang. The rate of star birth in the universe increased by ten times during this 170-million-year period, Illingworth said. “This is an astonishing increase in such a short period, just 1 percent of the current age of the universe,” he said. There were also striking changes in the numbers of galaxies detected. “Our previous searches had found 47 galaxies at somewhat later times when the universe was about 650 million years old. However, we could only find one galaxy candidate just 170 million years earlier,” Illingworth said. “The universe was changing very quickly in a short amount of time.”

The Hubble Ultra Deep Field WFC3/IR Image. This Region of the Sky Contains the Deepest Optical and Near-Infrared Images Ever Taken of the Universe and is useful for finding star-forming galaxies at redshifts 8 and 10 (650 and 500 million years after the Big Bang, respectively). At UCSC and Leiden, we are using these data to better understand the properties of the first galaxies. Credit: Bouwen

According to Bouwens, these findings are consistent with the hierarchical picture of galaxy formation, in which galaxies grew and merged under the gravitational influence of dark matter. “We see a very rapid build-up of galaxies around this time,” he said. “For the first time now, we can make realistic statements about how the galaxy population changed during this period and provide meaningful constraints for models of galaxy formation.” Astronomers gauge the distance of an object from its redshift, a measure of how much the expansion of space has stretched the light from an object to longer (“redder”) wavelengths. The newly detected galaxy has a likely redshift value (“z”) of 10.3, which corresponds to an object that emitted the light we now see 13.2 billion years ago, just 480 million years after the birth of the universe. “This result is on the edge of our capabilities, but we spent months doing tests to confirm it, so we now feel pretty confident,” Illingworth said.

The galaxy, a faint smudge of starlight in the Hubble images, is tiny compared to the massive galaxies seen in the local universe. Our own Milky Way, for example, is more than 100 times larger. The researchers also described three other galaxies with redshifts greater than 8.3. The study involved a thorough search of data collected from deep imaging of the Hubble Ultra Deep Field (HUDF), a small patch of sky about one-tenth the size of the Moon. During two four-day stretches in summer 2009 and summer 2010, Hubble focused on one tiny spot in the HUDF for a total exposure of 87 hours with the WFC3 infrared camera.

“NASA continues to reach for new heights, and this latest Hubble discovery will deepen our understanding of the universe and benefit generations to come,” said NASA Administrator Charles Bolden, who was the pilot of the space shuttle mission that carried Hubble to orbit. “We could only dream when we launched Hubble more than 20 years ago that it would have the ability to make these types of groundbreaking discoveries and rewrite textbooks.”

To go beyond redshift 10, astronomers will have to wait for Hubble’s successor, the James Webb Space Telescope (JWST), which NASA plans to launch later this decade. JWST will also be able to perform the spectroscopic measurements needed to confirm the reported galaxy at redshift 10. “It’s going to take JWST to do more work at higher redshifts. This study at least tells us that there are objects around at redshift 10 and that the first galaxies must have formed earlier than that,” Illingworth said.

“After 20 years of opening our eyes to the universe around us, Hubble continues to awe and surprise astronomers,” said Jon Morse, NASA’s Astrophysics Division director at the agency’s headquarters in Washington. “It now offers a tantalizing look at the very edge of the known universe — a frontier NASA strives to explore.” How far back will we go? If you sit around a campfire watching the embers climb skywards and discuss cosmology after an observing night with your astro friends, someone will ultimately bring up the topic of space/time curvature. If you put an X on a balloon and expand it – and trace round its expanse – you will eventually return to your mark. If we see our beginnings, will we also eventually see our end coming up over the horizon? Wow… Pass the marshmallows, please. We’ve got a lot to think about.

Reader Info: Illingworth’s team maintains the First Galaxies website, with information about the latest research on distant galaxies. In addition to Bouwens and Illingworth, the coauthors of the Nature paper include Ivo Labbe of Carnegie Observatories; Pascal Oesch of UCSC and the Institute for Astronomy in Zurich; Michele Trenti of the University of Colorado; Marcella Carollo of the Institute for Astronomy; Pieter van Dokkum of Yale University; Marijn Franx of Leiden University; Massimo Stiavelli and Larry Bradley of the Space Telescope Science Institute; and Valentino Gonzalez and Daniel Magee of UC Santa Cruz. This research was supported by NASA and the Swiss National Science Foundation. Hubble Ultra Deep Field Image and Video courtesy of NASA/STSci.


Tammy is a professional astronomy author, President Emeritus of Warren Rupp Observatory and retired Astronomical League Executive Secretary. She’s received a vast number of astronomy achievement and observing awards, including the Great Lakes Astronomy Achievement Award, RG Wright Service Award and the first woman astronomer to achieve Comet Hunter's Gold Status.

Torbjorn Larsson OM January 26, 2011 at 1:03 PM

If we see our beginnings, will we also eventually see our end coming up over the horizon?

I don’t see what this is getting at. In a hyperbolic open geometry of relativistic light cones, wouldn’t the horizon become incredibly expanded right when it dims out? The likelihood of seeing any bounded volume would go to zero. (Also, inflation adds to the final blow up.)

Mostly though, the balloon analogy is a closed geometry, and eventually it doesn’t apply at those scales.

ello January 26, 2011 at 1:40 PM

“The newly detected galaxy … , which corresponds to an object that emitted the light we now see 13.2 billion years ago…”

In the ever expanding universe, so we are told, galaxies are moving away from one another constantly. Suppose the average speed that galaxies move away from one another is 10% the speed of light (a huge, huge speed), it’d take 132 billions years for our Milky Way galaxy to be physically located 13.2 billion light years away from this newly discovered “tiny galaxy”, no? But that makes the age of the universe at least 132 billion years old, no? Why is everyone saying the universe is only 14~15 billion years old? I’m confused…

solarx2 January 26, 2011 at 4:19 PM

i think it’s because lambda CDM model predicted the age and then accurate measurements of the CMB redshift showed that same number as was predicted; 13.7 bn years. it seems the universe expanded very rapidly during inflation, leaving a universe that was bigger in light-years than it was in age. i might be wrong here, it seems hard for me to confirm since im not a scientist and cant do math. i just read a lot of wikipedia. :)

Lawrence B. Crowell January 26, 2011 at 7:14 PM

The scale factor, a function of time the rescales distances x’ = ax, for the universe expands exponentially

a = exp(sqrt{/\}t)

in the de Sitter metric or spacetime. The distance one observes on a path is S and that distance in time t and a radial distance r is

S^2 = (ct)^2 – ar^2.

A light particle is such that S = 0 and you get the expression in r and t

(r/t)^2 = c^2/a.

So the speed of light at a distance appears to “slow down,” even though locally it is a strict constant.

The spatial manifold is expanding exponentially. As such particles are frame dragged along with that expansion. A galaxy observed with z = 8 is being framed dragged by the expansion of space away at 8 times the local speed we measure for light. It is moving not by ordinary velocity, but due to the fact it is commoving along with the expansion of space. It might be asked how it is that we can observe them. A photon emitted by this galaxy will pass through regions which have a slower expansion rate, and as a result reach us.


Lawrence B. Crowell January 26, 2011 at 7:17 PM

I forgot to indicate this is the reason the spatial extent of the universe is larger than one might expect in light years. The distance out to the CMB is about 65 billion light years. The distance to the region where we could observe (by gravity or neutrino physics) inflationary expansion in the very early universe is about 10 trillion light years away.


powercosmic January 28, 2011 at 11:49 AM

Your observation is very intuitive, but let me try explain, based on modern cosmological theory, how this galaxy could be so far away.

The speed of light is only the speed limit for matter or energy moving through space, however, it is not the speed limit for the speed at which space-time can expand.

The space-time continuum can even expand faster than the speed of light and in fact it is, the galaxies at these distances didn’t “fly” to their positions in space to them they are “carried along” by the expanding space-time in much the same way that a boat is carried on a river.

In this way, things can travel faster than the speed of light.

Hon. Salacious B. Crumb January 28, 2011 at 12:00 PM

In one word. No.

Tammy Plotner January 26, 2011 at 2:36 PM

have a few more marshmallows… it’s been a long observing night and it’s an ever expanding balloon… at least until joe pokes it with a hot stick pointing out the X and then all bets are off. bang! ;)

Torbjorn Larsson OM January 31, 2011 at 6:42 AM

What a party popper!

Fair enough.

fletchphoto January 26, 2011 at 2:46 PM

Hi all, I’m new to this site and astronomy thing, but find this site very interesting and informative. It also makes my mind work which is a bonus! The above post has raised a question in my head. The ‘new’ galaxy is measured as being 13.2 billion light years away from us which gives an estimate of 14-15 billion years for the age of the universe. But surely this figure would only be correct if WE were in the centre of the universe. Are we simply measuring the distance that galaxy is away from our point in the universe to get this figure,when it should be the distance it is from the centre of the ‘big bang’? As I say, I am new to all this so excuse me of my ignorance but it is all very interesting.

Uncle Fred January 26, 2011 at 5:28 PM

Fletchphoto, this is common misconception, and one I had for a very long time. The big bang had no center or “singular location in space.” In fact, the big bang happened simultaneously everywhere. It is not so much an explosion of stuff but the beginning of the expansion of space itself.


Hope this helps.


fletchphoto January 27, 2011 at 10:38 AM

Mmm interesting, so more like the big ‘snap crackle and pop’ than a singular bang? LOL Thanks for your answer, I am sure I will have more…

Olaf January 27, 2011 at 10:59 AM

The interesting thing is that the aliens at the furthers galaxies would see the exact same thing when they looked towards Earth. Galaxies moving away from them and Earth not existing yet.

Uncle Fred January 27, 2011 at 10:30 PM

Which is one of the reasons why Aliens aren’t likely coming here to visit/abduct us. Depending on how far away they are, they might see in their scopes an early Earth, one before humans even existed.


Tammy Plotner January 26, 2011 at 3:06 PM

i think you’ve raised an excellent point (and obviously had a marshmallow or two in your time). As expressed in the NASA press release: “Astronomers don’t know exactly when the first stars appeared in the universe, but every step farther from Earth takes them deeper into the early formative years when stars and galaxies began to emerge in the aftermath of the big bang.” so here we have a “earth-centric” point of view. (ah, ptolemy… what we wouldn’t give to smoke a marshmallow or two with you, eh?)

more than anything, i believe the excitement is about seeing how early galaxies formed: “The hypothesized hierarchical growth of galaxies — from stellar clumps to majestic spirals and ellipticals — didn’t become evident until the Hubble deep field exposures. The first 500 million years of the universe’s existence, from a z of 1000 to 10, is the missing chapter in the hierarchical growth of galaxies. It’s not clear how the universe assembled structure out of a darkening, cooling fireball of the big bang (joe’s stick?!). As with a developing embryo, astronomers know there must have been an early period of rapid changes that would set the initial conditions to make the universe of galaxies what it is today.”

and that raises even more questions, doesn’t it?

Uncle Fred January 26, 2011 at 5:31 PM

Darkening cooling fireball? Huh?

Astrofiend January 26, 2011 at 8:33 PM

“ah, ptolemy… what we wouldn’t give to smoke a marshmallow or two with you, eh?”

Smoke a marshmallow? ‘Marshmallows’ are what the kids are calling them these days, eh? :)

ello January 26, 2011 at 3:45 PM

So you are saying the big bangsters took a big leap of faith? The universe came from no where, then somehow managed to have scattered matters billions of light years accross in a few hundred million years? You are toying with us and my marshmallow is tasting funny :)

Fletch, I don’t think they are assuming the earth is at the center of the universe. Since the universe is expanding, every part is moving away from every other parts. From the earth’s point of view, everything is moving away from us. And so is the view seen from any corner of the universe. The life span of the universe is calculated by back tracing to the origion of the big bang based on the speed of the expansion along with other things such as leap of faith :)

Lawrence B. Crowell January 27, 2011 at 4:33 AM

The universe is in effect a big nothing. You might think of gravity with its negative potential energy as exactly matching the positive energy of matter. Hence the “sum over all = 0.” The local appearance of matter-fields is due then to a particular configuration of the vacuum state. This confuguration occurs due to a quantum fluctuation, or an uncertainty tunneling process. The trigger for the big bang was likely a quantum fluctuation that is not too different from what occurs in radioactive decay.


Hon. Salacious B. Crumb January 26, 2011 at 4:19 PM

Sorry. This is a poorly constructed article, as it leaves to many holes explaining what this discovery really means. Worst is;

- What is the relation of image 1 to image 2. I.e. Is this new galaxy in the first image?
- You haven’t stated how old the universe is.
- You have 9 separate numbers quoting ages after the Big Bang
- Your reply with “z of 1000 to 10″, but you don’t explain what “z” is or its relationship to velocity nor distance. (It is not linear, as poor confused ello states.)
- The standard method describing galaxy distances, is via their redshift and the inferred age. It is never counted from the time after the Big Bang, as the measure relies on the Hubble Constant (H0) derived from the expansion and not from the immeasurable time after the Big Bang. Time after the Big Bang is deduced not measured!
- Then you go flippantly start trivialise it with irrelevant marshmallows!

I don’t understand this story and I’ve actually written a paper on galaxy evolution and Population III stars!

Peter January 26, 2011 at 4:42 PM

Salacious as always, prefers to nitpick in his barely decipherable english. When you are attempting to make a point, Sal, it really does help to speak it clearly. Who is “you”, the age of the universe is clearly stated in the article, z is explained as red shift, “your reply” refers to nothing at all, “too” is the comparison spelling (as in too large), and I hope you were kidding about the marshmallows.
Ello, you haven’t considered the inflationary time after the Big Bang. The universe did not expand at a constant speed but boinged into existence some large fraction of its present size. Then the rate of expansion slowed and then started getting faster again. Universes, geez, you can’t trust ‘em for a second!
So you’d be right about the age if it had expanded from zero evenly but apparently it didn’t. If in every single direction there are galaxies at those distant red shifts then clearly, normal physics didn’t apply for much of the expansion if the stated age of the universe is correct.

Hon. Salacious B. Crumb January 27, 2011 at 3:08 AM

Thank you for your kind words. They are gratefully appreciated.

PhelanKA7 January 26, 2011 at 5:48 PM

It’s HAN Solo. Not HANS.

Tut, tut.

Vanamonde January 26, 2011 at 6:45 PM

YES! Hubble just keeps on! Great work!

And speaking of Population III, i am sure that we may been to wait for James Webb or beyond to get a specutrum from this beasties, but it could it be a metal free galaxy?

Planets of superconducting helium with hydrogen metal crusts?
Fountains of Helium II?

Paul Eaton-Jones January 27, 2011 at 1:38 AM

I blame the venerable Sir Fred Hoyle for the continuing use of the term Big Bang! He coined the phrase in a perjorative sense in the 1950′s as a way of ridiculing the ‘new’ theory which challenged the then accepted/predominant idea of the Steady State Universe. I believe he did come round to the idea of an initial starting point though he was never entirely comfortable with the idea. Unfortunately we’re now stuck with the idea of a ‘bang’ and newcomers/laymen are always confused by the concept. Of course we’re not helped when virtually EVERY science programme dealing with cosmology uses chemical explosions and explosive imagery to get the point across.

Question January 27, 2011 at 1:52 AM

you guys out there with the questions keep asking! don’t let condescension put you off. remember to take EVERY COMMENT here with a grain of salt because much of what are being presented as facts are based on very young theories which have yet to stand up to the scrutiny of time.

read what is written and then do your own research. when you do, you will notice that there is far from a true consensus on probably about 75% of what we discuss here.

Hon. Salacious B. Crumb January 27, 2011 at 3:00 AM

Eh? Good on you mate, but I question your motives. Firstly a really nice broad based slur here. Why not, let’s tar everyone with the same brush. Isn’t it nice to see the wannabe psuedo-scientists still drumming up the negative rhetoric against “facts” in what should really be rudimentary basic science.
Frankly, just because you don’t understand it doesn’t mean it is wrong. So your solution is that it might be best to drag everyone else down to the your same level of ignorance. (Basic psychology actually.)
Sadly your “grain of salt” opinion is “yet to stand up to the scrutiny of time”, as you offer no “facts” to support your claims.

Olaf January 27, 2011 at 11:17 AM

@Question, instead of using a psychology trick and wordplay you should actually give a fact. What claim is wrong?Why is it wrong? Not fuzzy wordplay, just hard facts.

Question January 27, 2011 at 4:13 PM

olaf, where have i claimed that anything was “wrong”? i object to the certainty with which certain very new theories are readily gobbled up after the most cursory of evidence (in some cases simply a sim with plug-in numbers), and then zealously defended when called into question.

you ask me for facts. you’ll have to be a little more specific. i would like to say however that the whole point of my statement was to encourage readers to be mindful of what are given to them as facts, so you’ll understand my reluctance to start spewing out “facts” of my own. i do have objections to at least two of the theories mentioned in this very thread, but i’m not going to tell you what they are because: a) they will no doubt fall on deaf ears, and b) because i don’t really care or feel the need to convince anyone of anything. i encourage them (and you) to be independant thinkers.

salacious, i have no problem with you questioning my motives in warning people to be cautious, but the rest of your response is incoherent. in order to try to understand your point, can i ask you for a specific example of something that i don’t understand and am therefore attacking? if you don’t have anything specific then perhaps you can present me with one of your theories that you think i’d object to, since you seem to know me (and my motives) so well…

Hon. Salacious B. Crumb January 27, 2011 at 7:07 PM

OK. I’ll bite.
What “very new theories” are you’re talking about?
What “new theories” “have yet to stand up to the scrutiny of time”?

Yet you then paradoxically claim “you’ll have to be a little more specific.” Eh? YOUR the one who is claiming something is wrong in what is being presented — “75%” of it to quote you directly.

Yet now, and quite bizarrely, “you can present me with one of your theories that you think i’d object to” Eh? Your making these claims, no me! (I’m not a mind reader, you know.)

As for;
“i do have objections to at least two of the theories mentioned in this very thread, but i’m not going to tell you what they are because: a) they will no doubt fall on deaf ears, and b) because i don’t really care or feel the need to convince anyone of anything.”
How about the more likely; c.) I plainly don’t understand two theories?

Also as for your “attacking”, well what does this actually mean; “…you will notice that there is far from a true consensus on probably about 75% of what we discuss here.”

Yeah like what?
Where is the proof of this statement?
Specifically what 75% of what we discuss here?

Face it. You have made this bold statement to attempt to persuade others this is somehow wrong or the results are mostly questionable. Therefore everything in what you’re saying is just totally empty rhetoric, as you offer absolutely no proof. You made the statements. So back it up!

Question January 28, 2011 at 4:00 PM

salacious, you accused me of attacking theories because i don’t understand them. i asked you to supply me with a specific example of where i did this. you did not (could not) do so, and then accused me, as OLAF did, of claiming that something was “wrong” when i did nothing of the sort. you probably didn’t read my response to OLAF or you would not have repeated his error. your (continued) assertion that people who object to theories do so only because they do not understand them is simply archaic and quite frankly paints you as an insecure conformist at worst and a closed-minded thinker in the least.

after doing some reading of other articles on this site, i have discovered that you have taken the roll of resident troll here. i’m not interested in getting involved with any of that. i’ll ask that from this point onwards you leave me alone and i’ll do the same for you. it doesn’t sound like we have much to learn from each other anyhow…

Hon. Salacious B. Crumb January 28, 2011 at 5:26 PM

I’ll repeat;
What “very new theories” are you’re talking about?
What “new theories” “have yet to stand up to the scrutiny of time”?
“…you will notice that there is far from a true consensus on probably about 75% of what we discuss here.”

If you can’t answer the claims, then what are you talking about?

Hon. Salacious B. Crumb January 30, 2011 at 1:39 AM

Like most cowards, they openly accuse you of everything in the world, and then when someone challenges them and points out their wrongs or distortions, they cannot even answer their own accusations.
I still find it extraordinary that if someone disagrees or doesn’t understand a topic, they go all out to destroy the credibility of those who do understand the complexities then just ignore everything regardless of the evidence or the facts in front of them.
“Question” poorly tries to get some personal attention that every comment in this story is wrong and that there is no consensus regarding most aspects of cosmology. Really, all he wants is to fool or trick those who don’t know better, so they can be fooled and tricked towards his own or wrong beliefs.
In the end the more people refuse to listen, the more desperate they crave some attention there way.

As most continue to say, you should avoid or ignore the trolls, but the problem is that is exactly what the trolls want. They slot in there usual diatribe, knowing it will be likely ignored, but the seed of doubt they want sown remains seen in the current discussion and then held in prosperity when the article is archived. This all seems to be OK to those who know better, but the real target is often those novices who don’t know the basics very well. Wanting to undermine even basic science is a sin that should not be tolerated, especially in the open attacks often presented here.

[Note: From his attitudes and writing style (no punctuation, long sentences, no capitaization, etc.) sound exactly like PC/EU proponent 'Quantauniverse', or 'Jimhenson', who wants us to believe the universe is infinite and has no beginning, all to just to satisfy his crazy electric universe nonsense. I do not know if this is him, but the general behaviour seems very much the same]

Torbjorn Larsson OM January 31, 2011 at 6:54 AM

very young theories which have yet to stand up to the scrutiny of time.

the most cursory of evidence

The standard cosmology is standard because a) it has been tested several times (by supernova results, WMAP, et cetera) b) it sums up _all_earlier evidence. You don’t really know how science works or what it results in, yet you try to argue against.

In similar vein, your “sim with plug-in numbers” is a fair description of all theories (aka testable models with certain parameter values). And so on.

Hon. Salacious B. Crumb January 27, 2011 at 4:59 AM

There is another article on this story similar to this at the New York Times website;

Also note that this z=10 galaxy is as yet to be confirmed, hence the author’s “candidate redshift” in the title of their Nature paper.

ello January 27, 2011 at 7:00 AM

Many thanks to everyone who attempted to answer my question. Although I still don’t understand all the intricacies, one thing is clear: the expansion of the universe is NOT linear.

Cliches like “Hubble looking back in time” have puzzled me for years. I’m pretty sure I am not alone. It is as if an object 10 billion light years away is actually a thing 10 billion years in the past, or (10 billion) x (the speed of light) spatial miles away. In this regard I think astronomers and journalists in astronomy have done a poor job in explaining the concept. Granted certain things probably are too hard to explain to laymen like myself. Still, if mind boggling concepts like the “big bang” can be pushed through the general public, we’ll manage to cope with the 10 billion is actually not 10 billion idea as well :)

Hon. Salacious B. Crumb January 27, 2011 at 8:43 AM

Simply. Distance and time are related to the speed of light. If you feel, say, the sunlight on your skin, the heat you feel has travelled the gulf of 150 million kilometres (93 million miles). Now light travels at a finite speed of 300,000 kilometres (186,000 miles) per second. Basic calculation, shows that light has taken (distance divided by speed) 500 seconds or 8 minutes 20 seconds to you feel the sunlight.
So although the warm of the sun seems instantaneous, it has actually left the sun 8 minutes 20 seconds ago. This was eight minutes in the past. If we see a sunspot on the solar disk, we see the sunspot as it was 8 minutes 20 seconds ago.
Now most astronomical objects lie much further than the Sun. The nearest naked-eye star is Alpha Centauri, whose distance is about 4.4 light-years away. This means light takes 4.4 years to leave the stellar disk and travel to Earth. You see the star, but the light you look at is 4.4 years old. It left Alpha Centauri in about August 2006, which is in the past.
So in the view, astronomy is actually a historical science, because the light we see from every astronomical object is in the past.

When we say “Hubble looking back in time”, that is what we mean.

Now regarding this galaxy. Astronomers have found that if we look at a galaxy its light does something odd. Its light changes colour. The further the galaxy is away, the greater the amount of colour change appears. (this is why it is called red-shift or Doppler redshift.) In the 1929, Edwin Hubble found something curious. If he looked at many galaxies, he found that the further the galaxy was away from us, the faster this redshift (the velocity or speed) became. Hence, the galaxies are, (except for the very closest ones), all seem to be moving away from us. The further they were away the faster they were appearing to move.

Hubble famously plotted a graph and found an important relationship, in that if he could measure the redshift of some unknown galaxy and multiplied it by a constant (the so-called Hubble Constant), he could then workout how far the galaxy was away from us.

This constant is presently found to be about 73 kilometres per second (speed) for every megaparsec (roughly 3.3 million light years). This means for every 3.3 million light years the velocity increases by 73 kilometres per second. Hence at 6.6 million light years, the speed of the galaxy moving away from us in doubled. 73 times 2 or 146 kilometres per second, etc.

The most distant galaxies are moving at a high velocity near the speed of light. I.e 280,000 km per second (or 174,000 miles per second) being 93% of the speed of light.

As astronomers don’t like messing with big number, they use a value called ‘z’ is a way of expressing this redshift. (For our purposes, it is the amount of the observed colour shift seen with a galaxy.]

If z=1, the distance of the galaxy is about 10.5 billion light years. The age of the observed galaxy is 7.5 billion years. (Roughly the age of the solar system)

If z=2, the distance of the galaxy is about 16.3 billion light years. The age of the observed galaxy is 10.0 billion years.

If z=10, the distance of the galaxy is about 30.6 billion light years. The age of the observed galaxy is 470 million years.

[These results will depend on many other parameters, such as the Hubble Constant (which for the value above is 73kps per megaparsec), if the universe is either 'open' or 'flat', etc. These are little corrections made by the cosmologists.]

You can calculate this all yourself with the NASA/IPAC EXTRAGALACTIC DATABASE calculator; http://www.astro.ucla.edu/%7Ewright/CosmoCalc.html

Note: Input the value of ‘z’ (top left corner), push the “General” button, and the results are calculated for you!

Hope this helps.
Cheers :)

Please: I’ve taken some shortcuts to explain the concept simply. I’d recommend you read say ‘redshift’ etc., on Wikipedia for more specific detail.

Hon. Salacious B. Crumb January 27, 2011 at 9:00 AM

Correction: “If z=10, the distance of the galaxy is about 30.6 billion light years. The age of the observed galaxy is 470 million years.”

This should read;
“If z=10, the distance of the galaxy is about 30.6 billion light years. The age of the observed galaxy is 13.3 billion years.”

The 470 million years here is the amount if time after the ‘Big Bang.’ I.e. When the galaxy was 470 million years old.

Also the Solar System’s age is 4.5 billion years. I should have said 1½ times the age of the Solar System! Sorry.) (7.5 billion years is the closest event that we can easily relate too.)

ello January 27, 2011 at 1:08 PM

Thanks so much for your explaination! Now I completely understand where things went wrong for me: I assumed the speed at which the universe is expanding is a constant. But it is actually accellerating. I had no idea galaxies at distance could be moving close to the speed of light. Such accelleration explains why galaxies can travel much longer distance than otherwise moving at a constant speed. When I have time, I’ll try to deduct the distance/time relationship formula myself. It wouldn’t be too hard since we know the accelleration value. The distance would simply be the accelleration times a finite integral of time with respect to time. I’d be proud of myself if my result comes close to distances indicated by the values of ‘z’ :)

Anway, I am so glad to finally understand that there is no fuzzy logic here when we say “Hubble looking back in time”. The time is accurate. So is the distance (light really traveled that many light years to get here).

Hon. Salacious B. Crumb January 27, 2011 at 2:52 PM

One clarification…. You said; “I had no idea galaxies at distance could be moving close to the speed of light.”
In reality, they are not moving at the speed of light they APPEAR to move at the speed of light. If you were on the z=10 galaxy looking back at the Milky Way, we would be moving at close to the speed of light too. It is also as Olaf said;

“The interesting thing is that the aliens at the furthers galaxies would see the exact same thing when they looked towards Earth. Galaxies moving away from them and Earth not existing yet.”

This implies that the galaxies are not just running away from the Milky Way and us, but no matter what galaxy you live in the universe, they are all aged 13.7 billion years old (from their point of view), and see the same expansion of the universe — equally looking back in time to when the galaxies were formed eons ago. Expanding of space is a question of geometry not a phenomena exclusive to one galaxy or another, one place or another..

Why we believe in the Big Bang.

Also you should noted that it is space that is expanding, meaning it is getting larger as it gets older. The reason we believe the ‘Big Bang’ occurred, is that if we wind the clock backwards, we get to a place where space shrinks to nothing — a zero point, if you like — a place where the universe seems to have started. Yet, not only did space start, but so did time. We believe that the Big Bang was the start of everything in the Universe, and before the big bang doesn’t make any sense, because there was no space and no time, and nothing of substance in it.

This is why it was incorrect when you said “So you are saying the big bangsters took a big leap of faith?” Actually, it is based on redshift observations of many many galaxies, based on observational evidence. Many seem to think this is all some contrivance; I.e. Redshift must be wrong or are being caused by something else. It is not. Einstein used it to prove the concept of an expanding universe through relativity, Hubble found the observational proof for it. What astronomers are trying to do is to piece together the history of the universe from when the first stars and galaxies formed and how they evolved to be like the galaxies like the Milky Way and its neighbours.

Hope this helps all your questions and doubts.

Note; if you would like to read more, I suggest you read the excellent Universe Today series of articles under “The Universe” by Fraser Cain and several authors at http://www.universetoday.com/36425/the-universe/

[My explanation here is a bit more simpler than these articles appear to be, but at least it will give you more food for thought. Perhaps Tammy or Fraser might consider doing a 'nutshell' story to piece it all together?]

ello January 27, 2011 at 1:14 PM

I bet the the word is spelled as ‘acceleration’…

powercosmic January 28, 2011 at 11:58 AM

I noticed some intuitive comments that ponder how could it be that the galaxy is being observed as it was 13.2 BILLION years ago, therefore the light has been enroute to us at the speed of light.

This is a problem because it is intuitive that the galaxy would have had to “fly” to its present position at the speed of light, which seems impossible.

But, this “flying” through space is not what happened, instead the galaxy has been sitting in roughly the same position while the “fabric” of space itself expanded, the fabric of space can and is (at this very moment) expanding faster than the speed of light, and this is how the galaxy got to be so far away.

Hon. Salacious B. Crumb January 28, 2011 at 12:09 PM
Daniel Rey M. January 29, 2011 at 3:12 PM

Whenever the Big Expansion is explained someone’s liable to say, as someone has done here, that there was no point somewhere from which it spread, as from a hub, but that “it happened everywhere”, without saying how this can make any sense. Not only…

1) does this make no sense if you don’t add that it happened everywhere because (supposedly) that point of infinite density, a “singularity”, was, theoretically, all that there was, and that once it started then, magically, all of a sudden, there was space and time, and so it makes no sense to ask what came before that because there was no “before”, and the point was not in a state of abeyance or a latent state in any previously existing space to which it expanded, but it invented space as it expanded itself, and this space is not surrounded by anything, but…

2) it still makes no sense even if you go into that additional clarification because…

a) nothing can spring forth from nothing because nothingness is nonexistent by virtue of its own definition, and…

b) you can’t have something spatial surrounded by something that is nonspatial, nonexistent, or whatever.

You can play around, if you like, with the notion of a plane of reality where time doesn’t exist, and claim that on those planes of reality where it seems to exist it is an illusion created by consciousness (sentience), but what you can’t do is try and have it both ways and say that once upon a time there was no time (and space) and then all of a sudden there was time (and space). Every instant implies a previous instant and a following instant. If you want to play the time game then you have to be consistent: you can’t have a state of affairs where there’s such a thing as time and a state of affairs where there is no time unless you’re a mystic.

The notion that a singularity invented time and space is a desperate one that they come up with because they see no other way to explain the coming of the Expansion. That’s why they refuse to discuss the Beginning, and they start out by telling the story as it started to unfold a few instants after the Expansion began.

None of the above is to be taken seriously. It’s a tongue twister with no purpose except to befuddle rather than to enlighten, an exercise in sophistry, so that the errors in logic can be found.

Mr. Muppet Jr.

Hon. Salacious B. Crumb January 30, 2011 at 12:48 AM

No. You’ve seen the observations in the universe expansion from the galaxies, and if you playing the movie backwards, you come to the main conclusion that the universe as we know it had a beginning — the so-called “Big Bang.”
Evidence is also from the microwave cosmic background radiation, that appears in every direction.
If all matter was created in this one singular event that gave substance to the universe, then what happen before it? Logically if there was nothing in the universe, then we cannot have any events to “time.”
We also measure its temperature as 2.7K, the temperature above absolute zero, and again winding the clock backwards, we can conclude that the earlier universe was hotter. Cosmologist suggest at the time of the universe’s creation, the temperature was so high, that matter we see around us to day was in a more primordial state. In the moments after the beginning, all matter and the forces that control matter (gravity, the electromagnetic, and the strong and weak nuclear forces) came into being. (Atom smashes, like at CERN, can even investigate, what likely happened and the relationships between matter and the four fundamental forces.)
Also you mention nothing about quantum mechanics, and the universe creation by a quantum fluctuation. (Who says “That’s why they refuse to discuss the Beginning,”?)

I’d suggest you look a it deeper into the topic before making sweeping claims as you have done here. Many of the things you state in your words above are incorrect. As they say; you can find much beauty in the detail.

Again, just because you don’t understand it doesn’t mean it is wrong.

(From your negative words here I assume you believe in god’s creation in seven days. Equally I could argue in a similar way to what you have said above, and even how more implausible that creation seems.
One counter argument, is if you believe that the universe was created by some omnipotent being, is what did he leave real observational evidence for us humans to discover? Did he not anticipate the humans innate curiosity to find how the creation of his world and universe came about? Frankly if you support some dogma over the observed evidence that we learn and continue to learn, then you have not taken into account the nature and purpose of being human — and that is far sadder than what you’ve said here.)

Hon. Salacious B. Crumb January 30, 2011 at 1:45 AM

I meant; “One counter argument, is if you believe that the universe was created by some omnipotent being, is why did he leave real observational evidence for us humans to discover?”

Daniel Rey M. February 1, 2011 at 9:23 AM

Why are those who dare question mainstream cosmology assumed to be ignorant Bible Belt redneck Creationist Fundamentalists???

” You’ve seen the observations in the universe expansion from the galaxies (…).” That’s some very odd syntax, almost incoherent, but one can infer the meaning behind it: the reddening and the redshift imply they’re all scattering in all directions, so it must be that they were once close together. It could be that the interpretation is only partly correct: the scattering could also be merely a manifestation of the expanding phase of an endless cycle of expansion and contraction similar to the heartbeat, with no Big Bang, no Big Crunch (either one of each or countless ones, as in the Bouncing Universe Theory), no ultimate scattering and going off of the lights, but just a gently throbbing Universe.

Besides, other explanations have been suggested for the reddening and the redshift, like the reddening caused by intervening dust particles and the eventual loss of energy in the electromagnetic waves.

” Evidence is also from the microwave cosmic background radiation (…).” The CMBR seems to be the only the most probable evidence, because the actual measurements by the COBE satellite fall exactly along the curve of the thermal spectrum predicted by the BB Theory, which is eerie. This background radiation could be, not “fossil radiation” from the initial flash, but “spent” radiation. In an eternal Universe electromagnetic waves could be expected eventually to shed energy, and revert to matter temporarily, rather than keep going forever and a day.

As for the other “evidences”, 1) dark skies (Olber’s Paradox) can be explained away simply by saying that, just as there is an infinite amount of starlight in an eternal Universe, so, too, there is an infinite amount of gas and dust clouds that will eventually deflect or absorb it, 2) the fact that if one looks far enough in all directions one sees what seems to be an earlier, more chaotic and violent Universe could mean that there are two clearly differentiated regions, with ours being a “bubble” surrounded by the other type, which would be a matrix full of such bubbles, 3) and the abundance of the two lightest elements agreeing with the predictions, and the fact that there is no known process in the stars that can manufacture them like the BB can, don’t mean that eventually some other phenomenon might be discovered that can explain that.

” Who says ‘That’s why they refuse to discuss the Beginning’?” Moderators at all scientific forums are constantly repeating that the BB Theory is unable to explain what elicited the Expansion and so what it restricts itself to discussing is what happened ever since some instants after that.

For example, this is what Chalnoth, Science Advisor at PhysicsForums, once said:

“(…) while there is a singularity in the math, the theory doesn’t include that singularity.

“One way of understanding it is this: the Big Bang theory assumes General Relativity. But we are quite sure that General Relativity cannot be valid above the Planck density. So we cannot trust the theory in any regime where it states there is a density near or above the Planck density. And the region around the singularity is one such regime.

“So the singularity is excluded from the theory, meaning the Big Bang theory says nothing whatsoever about any beginning of our universe.”

” One counter argument, is if you believe that the universe was created by some omnipotent being, (…) why did he leave real observational evidence for us humans to discover?” I’m not going into the matter of the genesis, but supposing there were a sentient being behind it, why would that being want to abstain from leaving behind evidence of its workings, like a criminal would do? In fact, if there were one such being, it will have left a trail that scientists are diligently following, whatever their beliefs concerning religious matters, and so scientists would have been assigned the task of following it up to the very end, when they might come face to face with the “fons et origo”.

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