How far back in time can we observe with our current technology and telescopes?

[meteor]

http://www.newscientist.com/news/news.jsp?id=ns99994686

The most distant object ever seen - a faint galaxy 13 billion light-years away - has been captured by two of the most powerful telescopes in operation.

The Hubble data suggest the newly observed galaxy lies between redshift 6.6 and 7.1, while long exposures with the Keck telescopes narrow the value to about 7.0.

 

[Orion1]

Genesis Galaxy...

Tapping the powerful Hubble Space Telescope and a rare quirk of cosmic physics, astronomers have discovered the most distant galaxy in the universe, a faint, record-setting smear of light that flared 750 million years after the big bang.

The infant galaxy, yet to be named, was found nestled among a massive galactic cluster known as Abell 2218. Richard Ellis, an astronomer at the California Institute of Technology in Pasadena and member of the discovery team, said the object is roughly 13 billion light-years away. One light-year is the distance light travels in a year, about 5.8 trillion miles.

Reference:
http://www.harktheherald.com/modules.php?op=modload&name=News&file=article&sid=14356&mode=thread&order=0&thold=0

 

[marcus]

Originally posted by meteor
http://www.newscientist.com/news/news.jsp?id=ns99994686

the technical article that goes with this is Jean-Paul Kneib et al
http://arxiv.org./abs/astro-ph/0402319

it is very interesting they could see such a small young galaxy
(only 2000 LY wide) so far back in time z = 7.0
in the article they call it "exploring the dark ages"
only got to see it by a lucky lensing accident
meteor thanks for posting the link!

 

[GerdankenDonuts]

Already replaced by another Abell

Abell 1835 IR1916

http://www.cnn.com/2004/TECH/space/03/01/farthest.galaxy.ap/index.html

 

[meteor]

"This galaxy appears to lie at a redshift of 10.0

Light from this galaxy may have formed a mere 460 million years after the Big Bang, which formed the Universe 13.7 billion years ago, say its discoverers".


http://www.newscientist.com/news/news.jsp?id=ns99994729

 

[marcus]

Originally posted by meteor
"This galaxy appears to lie at a redshift of 10.0

Light from this galaxy may have formed a mere 460 million years after the Big Bang, which formed the Universe 13.7 billion years ago, say its discoverers".


http://www.newscientist.com/news/news.jsp?id=ns99994729

The astronomer quoted is a woman by the name of Roser Pello. Maybe we can find the preprint.
Gedankendonuts and Meteor, thanks to you both for finding this item,
it's certainly exciting news. here's part of the article:
--------quote--------
Far-flung galaxy breaks record
01 March 04
NewScientist.com news service

A small, faint galaxy may claim the title of the most distant object known - breaking a record that was set just two weeks ago.

The new find appears to lie 13.2 billion light-years away from Earth and reveals what the earliest galaxies looked like.

Light from this galaxy may have formed a mere 460 million years after the Big Bang, which formed the Universe 13.7 billion years ago, say its discoverers.

The previous record-holder, reported in February 2004, dates back to 750 million years after the birth of the Universe.

"We are approaching the youngest ages of galaxies," says Roser Pelló, an astronomer at the Observatoire Midi-Pyrénée in France and co-leader of the discovery team.

...
...

The far-flung galaxy was discovered using one of the four 8.2-metre telescopes comprising the European Southern Observatory's Very Large Telescope (VLT) in Chile. Focusing on a single region of sky for an average of three to six hours at a time, the international team used an infrared imager and spectrograph called ISAAC to detect a single telling emission line that appeared to arise from hydrogen.

But the distant galaxy was only visible because of a chance geometric alignment. A massive galaxy cluster called Abell 1835 lies between the new galaxy and Earth. Abell 1835's gravity bent and magnified the distant galaxy's light, making it between 25 and 100 times brighter.

...

This galaxy appears to lie at a redshift of 10.0. The previous record holder for the most distant object is a galaxy at redshift 7.0, reported just two weeks ago by a team led by one of the researchers in this study.
...

However, the researchers themselves acknowledge the galaxy might lie closer than redshift 10.0. That could occur if the emission line arises not from hydrogen but from other elements, such as oxygen or nitrogen. A star-forming galaxy at redshift 2.5, for example, could account for the observed emission - but this would be unlikely to reveal the distinctive spectra seen, they say.
...

Named Abell 1835 IR1916, the new galaxy appears to form stars at the rate of between one and five suns per year and contains ten thousand times less matter than our Milky Way. Such small, star-forming galaxies are expected in the early Universe as they are thought to be the building blocks of the large galaxies seen today.

-----------end quote-----

 

[meteor]

Here's Roser Pello
http://webast.ast.obs-mip.fr/people/roser/

I was one time amazed when a friend of mine that was in a trip to the observatory of Midi Pyrenees told me that there they told him that the lights from my city (Barcelona) were harming the observations of the observatory. The observatory is more than 200 km away from my city!

 

[Nereid]

http://www.eso.org/outreach/press-rel/pr-2004/pr-04-04.html , which includes a link to the Pelló paper (near the bottom, cllick on "EDP web site")

 

[Nereid]

Originally posted by meteor
Here's Roser Pello
http://webast.ast.obs-mip.fr/people/roser/

I was one time amazed when a friend of mine that was in a trip to the observatory of Midi Pyrenees told me that there they told him that the lights from my city (Barcelona) were harming the observations of the observatory. The observatory is more than 200 km away from my city!

Can you find Barcelona and Observatoire Midi-Pyrénées http://earthobservatory.nasa.gov/Newsroom/NewImages/Images/earth_lights_lrg.jpg

 

[Lutherfan]

A question for anyone!

Hi, I just signed on to this forum because I am just at my wits end trying to imagine (I am not a scientist!) how we here on this Earth can see something so near to the big bang.

When I diagram out in my mind the big bang, it just doesn't add up - but I know that doesn't mean there isn't an explanation. Tell me where I am wrong:

1) the big bang throws out all the materials of the universe from one point of time and space at a speed of half the speed of light (for argument's sake - I don't know its actual speed - but surely it is somethin less than the speed of light).

2) It takes 10 billion years for the material of our star to make it out to the place we are at now (5 billion light years from the original point of the big bang.)

3) In my mind the light of any star that formed 450 million years after the big bang would have "passed" us some 4.55 billion years ago if it was located on the other side of the point of the big bang from us, and 5.45 billion years ago if that star was on this side of the big bang...

Another mind bender for you: I would think that if we can see a galaxy formed only 450 million years after the big bang, we should certainly be able to "see" the big bang itself. That would have been such an amazingly powerful event - plain as day to any astronomer... Please tell me where I am wrong on all of this...

 

[Nereid]

Lutherfan wrote: Another mind bender for you: I would think that if we can see a galaxy formed only 450 million years after the big bang, we should certainly be able to "see" the big bang itself. That would have been such an amazingly powerful event - plain as day to any astronomer... Please tell me where I am wrong on all of this...

Welcome to Physics Forums, Lutherfan!

First, the name "Big Bang" is somewhat of a misnomer; it wasn't really an "explosion" - that implies there's something for it to "explode" into - as it's the whole universe which is expanding, including space and time, ...

Next, regarding "seeing" the Big Bang. When you look at the Sun (DON'T DO THIS without proper eye protection!), whether in the optical part of the electromagnetic spectrum, or UV, or IR, or ... you can only see its 'surface', not the core where the energy is generated. Why not? Because the photons are scattered - they are emitted and absorbed, re-emitted and re-absorbed, ... vast numbers of times between when they are created (as hard gammas, in the nuclear fusion process) and finally emitted from the photosphere (as red, yellow, ... blue light).

The same sort of thing happened in the early years of the universe - the universe only became transparent to photons when (most of) the electrons combined with (most of) the protons to form neutral hydrogen. Like the visible 'surface' of the Sun, this part of the universe is called the 'surface of last scattering'.

And you can 'see' it! It's the 'cosmic microwave background' (CMB) or 'cosmic background radiation' (CBR), and was first detected in 1966 (?) by some telecom engineers. The most detailed and accurate picture of this earliest image of the universe has been produced by a space observatory called WMAP, and the study of this 'surface of last scattering' is one of most active areas of research in astronomy and cosmology today.

 

[Lutherfan]

Thanks!

This certainly helps me! The fog is clearing on those points made...

Actually, whole host of OTHER questions come to mind as well:
If we can pinpoint a galaxy so close to the big bang, we should be able to tell that that would be near the "center" of the universe... Do we actually observe that everything is moving away from that point? Why can't we look out to the "opposite" direction (from the center) and see the "leading edge" of the universe? It would seem to me that if the big bang did occur the material of the universe should be not very well distributed - most everything toward the outside edge with hardly anything in the middle. Nothing I have read seems to indicate this.

Now, I know the answers to questions like these probably depend on convoluted theories of time and space which are most likely incomprehensible to me... but maybe there is a website you know of that explains this all for more common folk?

Thanks!

 

[marcus]

Originally posted by Lutherfan
... but maybe there is a website you know of that explains this all for more common folk?

one strategy would be to stick with this website and keep asking questions
I did not see anyone here so far resent it if someone persists in asking about what he doesn't understand----not in astronomy anyway

does your name mean you are a fan of M. Luther?
I hope so, since he was an original and courageous person
if you are a fan do you know the name of his wife and how
they got her out of the nunnery so she could get married?

well, I will shut up so someone can come in and supply
names of introductory astronomy websites

there is no center to the "big bang" expansion, lots of people can explain this better so I won't try.
to me this seems subtle, elegant---a wonderful thing to have an expansion with no special point designated as center----expanding from everywhere at everywhere

just yesterday Nereid was using examples of rising bread to illustrate this----but cautioning that no illustration is completely reliable (any analogy has its limits)

 

[Lutherfan]

Yes!

In fact I am a "fan" of Martin Luther (not King Jr.) and interestingly, I used his wife's name (with a twist) as the password for this forum! A lover of God AND of knowledge and learning. A true "father" of our modern times.

 

[marcus]

Originally posted by Lutherfan
In fact I am a "fan" of Martin Luther (not King Jr.) and interestingly, I used his wife's name (with a twist) as the password for this forum! A lover of God AND of knowledge and learning. A true "father" of our modern times.

you qualify all right
obviously know a lot more than I do about M.L.
so you probabably know the story about the fish barrell


my candidate for the father of modern times would be kepler
who finished writing Harmonice Mundi three days after
the Defenestration of Prague

mother was Katherine Kepler, a contentious woman who barely
escaped burning as a witch

both men had strong writing styles, have to compare quotes
with you sometime. BTW several people here (selfAdjoint, quartodeciman and others) have told me interesting things about classical and renaissance history

this most distant object business is kind of exciting, must get back
on topic and save digression for another occasion

 

[Orion1]

Genesis Galaxy...

The galaxy, dubbed Abell 1835 IR1916, is 13.23 billion light-years from Earth -- beating by a chunk another galaxy that until now was believed to be the farthest known object, said France's state-funded National Center for Scientific Research, a major European research organization.

Because light from the new find took 13.23 billion years to reach us across the vastness of space, astronomers are seeing the galaxy as it was back then.

Reference:
http://www.sltrib.com/2004/mar/03022004/nation_w/144063.asp

 

[marcus]

Originally posted by Orion1
The galaxy, dubbed Abell 1835 IR1916, is 13.23 billion light-years from Earth --

Reference:
http://www.sltrib.com/2004/mar/03022004/nation_w/144063.asp

Ned Wright who teaches the graduate-level cosmology course at UCLA and is one of the scientists in charge of the WMAP project
gives the current distance as 31.5 billion LY to that object.

He gives a light travel time of 13.18 billion years IIRC.

Here's the link:
http://www.astro.ucla.edu/~wright/cosmolog.htm

it's in his "News of the Universe" section.

This is difficult to reconcile with your statement that the galaxy is "13.23 billion light-years from Earth" since it seems to be, on good authority, much farther than that----namely 31.5 billion.

If I remember right it was supposed to be around 3 billion LY when the light we now see was emitted, but the distance has expanded by a factor of 11 or so since then, hence the 31.5.

 

[Nereid]

Originally posted by Lutherfan
This certainly helps me! The fog is clearing on those points made...

Actually, whole host of OTHER questions come to mind as well:
If we can pinpoint a galaxy so close to the big bang, we should be able to tell that that would be near the "center" of the universe... Do we actually observe that everything is moving away from that point? Why can't we look out to the "opposite" direction (from the center) and see the "leading edge" of the universe? It would seem to me that if the big bang did occur the material of the universe should be not very well distributed - most everything toward the outside edge with hardly anything in the middle. Nothing I have read seems to indicate this.

Now, I know the answers to questions like these probably depend on convoluted theories of time and space which are most likely incomprehensible to me... but maybe there is a website you know of that explains this all for more common folk?

Someone in another thread (Russ?) pointed out something profound about the Big Bang and its centre ...

I imagine Lutherfan is sitting at a desk as he (she?) reads this, looking at a computer monitor, just as I am as I write this. Where's the centre of the universe, from which the Big Bang started? Well, both of us are looking at it; if we look up at the stars in a clear sky at night, every point of light up there is the centre of the universe, the origin of the Big Bang, ... and so on.

 

[ranyart]

Originally posted by Nereid
Someone in another thread (Russ?) pointed out something profound about the Big Bang and its centre ...

Nereid care to point (link?) us to this profound insight?

There are some questions of the Big-Bang that do not conform to everyday 'thinking' experience.

 

[Nereid]

I'll have a look ranyart, but it's the same as I just posted - everywhere you look is the 'centre of the universe'; everything you see (today) is where the Big Bang 'started from'.

ranyart wrote: If one was to be at the location of this recent detected 'Farthest Location-Galaxy', and were to look in the direction of our present Milky Way, one would find that the Milky way would not actually exist (on the Horizon of observation that is), the actual age of our Milky Way, I believed is related to the Luminosity function, and for a Galaxy that is say 1-000-000 Light years across, then this should be older by(999-999 lyrs) than a Galaxy that is just 1 light year across, gauged of course by our observations and calibrated to our reference point.

Not sure I follow this; swapping places with ranyart's counterpart in this distant proto-galaxy, looking in our directions (lots of caveats, but for the sake of discussion ... ), ranyart would 'see' the Milky Way as it was ~13 billion years ago. Is this older than the Milky Way itself (did the Milky Way form more recently than ~13 billion years ago)? It depends ... certainly we've not yet found any 'Population III' stars (the first generation, those which formed out of the primordial hydrogen and helium), and very few with very low abundances of heavier elements ... but they'd be difficult to find anyway.

Current thinking on the evolution of galaxies is that they're a bit like WorldCom - they grow by mergers and acquisitions, so the baryonic matter which presently makes up the Milky Way would have been in many small proto-galaxies, each ~1,000 ly in size, and a great deal more 'intergalactic' gas (no dust). One big unknown is whether there was a massive black hole - that is today Sag A*, and much more massive - or whether they came later.

 

[Stellar Tourist]

Didn't they say that the primordial gas expanded for 2 billion years before embryonic galaxies appeared.
The formation of a galaxy is a complex process, for this gas to condense in one area rather than another there had to be differences in density from place to another place. The distribution of matter at this stage was "too uniform" in order for galaxies to be created. This might be a fossil galaxy, fossil traces of inflation left their mark on the young universe and helped create cosmic strings. Tremedously dense matter and energy trapped in massive closed loops. There lumps of closed loops then became concentrated lumps of dense material ready to become a seed which drawed gas amd formed galaxies. The lumps became modified, space was knotted and ecah knot was a tiny region of space where energy was concentrated and distorted the geometry of space-time. That might be why so few galaxies came from the early life of the universe, because of expanisions, heat and inflation in the early life, gas could not cool into large clouds of cold dark matter.
Early Galaxy formations from hot matter has been considered and modeled using super-computers and the results have not been good, they can not explain hierarchical clustering.

 

[Nereid]

Do you have some links?

AFAIK, just about all the modelling is done with supercomputers, and the results are indeed model-dependent.

The proto-galaxy recently observed was certainly much smaller than the Milky Way - only ~1,000 ly.

The models which don't explain hierarchical clustering, IIRC, were hot dark matter ones - they assumed that the dark matter in the universe was 'hot' (moving at relativistic speeds); the cold dark matter models do a much better job of giving hierarchical clustering.

 

[Stellar Tourist]

I was reading some of this the other day

http://www.wkap.nl/prod/b/1-4020-0531-8

http://www.astro.soton.ac.uk/~crk/PH227/node40.html

http://grape.c.u-tokyo.ac.jp/~makino/papers/lscrev2_preprint/node3.html

http://curious.astro.cornell.edu/question.php?number=295

sorry, I've nothing about the modelling is done with supercomputers

 

[meteor]

JFYI, Abell 1835 IR1916 lies in the constellation of Virgo

It could be interesting to discuss when first galaxies formed. This existed 450 million years after Big Bang, but WMAP said that first galaxies formed 600 million years after Big Bang. It only shows that in cosmology, to give exact ciphers is a high-risk business

 

[Lutherfan]

Thanks for the web site!

I don't think that it was meant to answer my particular inquiries, but the Cornell website posted by Stellar Tourist really answered so many questions for me! Thanks guys.

 

[Nereid]

Originally posted by Stellar Tourist
I was reading some of this the other day

http://www.wkap.nl/prod/b/1-4020-0531-8

http://www.astro.soton.ac.uk/~crk/PH227/node40.html

http://grape.c.u-tokyo.ac.jp/~makino/papers/lscrev2_preprint/node3.html

http://curious.astro.cornell.edu/question.php?number=295

sorry, I've nothing about the modelling is done with supercomputers

Quick comments:
- GRAPE is a supercomputer (tho' a rather ancient one by today's standards! Grid computing can give much more grunt, e.g. http://www.zetagrid.net/servlet/service/statistic )
- 2dF and SDSS have given (2dF) and will give (SDSS) far more data on local clustering (etc) than mentioned in the second link.
- here's a http://zeus.ncsa.uiuc.edu:8080/GC3_Home_Page.html "devoted to harnessing the power of parallel computers to explore the origin of large scale structure in the universe and how galaxies form."

The Cornell site is a good one, isn't it!

[Edit: fixed formats]

 

[Orion1]

Universe Vastness...

The galaxy, dubbed Abell 1835 IR1916, is 13.23 billion light-years from Earth -- said France's state-funded National Center for Scientific Research, a major European research organization.

Most Distant Object Record Smashed

1 Mar 2004 - Pello et al. have found a galaxy much further away from us than any previously known. The evidence comes from a single line observed in the infrared which imples a redshift of z = 10. The source is seen magnified by a cluster of galaxies, Abell 1935, acting as a gravitational lens, and the source location is where sources with 9 < z < 11 should be very highly magnified. The colors of the source are also very consistent with z = 10. The technical paper and the press release both give pictures and spectra of this object. My Cosmology Calculator gives for z = 10 and the WMAP cosmic parameters (Ho=71, OmegaM=0.27 in a flat Universe) and age of the Universe of 0.48 Gyr at the time the light we see was emitted, a light travel time of 13.18 Gyr, and a current distance of 31.5 billion light years. This distance is much greater than the speed of light times the light travel time because the Universe has expanded by factors between 1 and 1+z=11 since the light did its traveling.

"13.23 billion light-years from Earth"
"a light travel time of 13.18 Gyr"

There is a general correspondence between the data with a deviation of only .05 Ly. However, the WMAP parameters does appear to be superior.

The Universe is far more dimentionally vast now at this instant in time than what is currently optically viewable through primordial radiation.

Integrating Hubble's Law into the average acceleration theorem yields the following solution:

WMAP H_o = 71 +/- 4 km/sec/Mpc

$$\Delta d_t = (d_f - d_i)$$ (31.5 BLy - 13.18 BLy)
$$a_u = 2 H_o^2 \left( \Delta d_t - \frac{nc}{H_o} \right)$$

a_u = 4.679*10^-10 m*s^-2

n - fractional luminous galaxy velocity
a_u - Universe Expansion Acceleration Rate
H_o - Hubble 'Constant'

$$H_o = \frac{ (V_i + V_f)}{ 2(d_f - d_i)} = \frac{ c(n_i + n_f)}{ 2(d_f - d_i)}$$

$$H_o = \frac{a}{(V_f - V_i)} = \frac{a}{c(n_f - n_i)}$$

According to these solutions, Hubble's 'Constant' is not actually a constant, but a function of the Universe Expansion Acceleration Rate and the differential galaxy velocities which compose it.

Reference:
http://www.astro.ucla.edu/~wright/cosmolog.htm
http://www.sltrib.com/2004/mar/03022004/nation_w/144063.asp

 

[zidane1strife]

I wonder if they'll find any significantly older ones? As in the 100-200 million years range.

 

[Nereid]

Originally posted by zidane1strife
I wonder if they'll find any significantly older ones? As in the 100-200 million years range.

We could do some calculations of our own, and estimate whether earlier objects could be detected or not.

Pello et al observed the Abell cluster, in various bands, using a VLT (8.4m diameter 'scopes?), for 3,000 seconds (V band) to 19,000 seconds (K_s band). The limiting flux $$F_\nu$$ is ~0.1 $$\mu Jy$$ (equiv to ~>28mag in the visible bands, and ~24 mag in the NIR ones).

Hubble's UDF took ~1 million seconds (ACS) in the BViz bands, and ~400k secs in the two NICMOS bands. The faintest objects are ~31 mag. The HST has a mirror diameter of 2.4m.

Assume they both observed z = 10 objects, and that Pello et al's is magnified by ~<100.

How long will the http://ngst.gsfc.nasa.gov/FastFacts.htm have to 'stare' at Abell 1835 IR1916 to detect it? To get at good IR spectrum? What about the faintest HST UDF galaxies?

How much fainter would a proto-galaxy at z = 20 be? What about a supermassive, 200 M_sol star (among the first stars to be formed)? How about such a star formed only 100 million years after the Big Bang?