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The most distant object

  1. Feb 16, 2004 #1
    http://www.newscientist.com/news/news.jsp?id=ns99994686

     
  2. jcsd
  3. Feb 16, 2004 #2
    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/module...article&sid=14356&mode=thread&order=0&thold=0
     
  4. Feb 17, 2004 #3

    marcus

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    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!
     
  5. Mar 1, 2004 #4
  6. Mar 1, 2004 #5
    "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
     
    Last edited: Mar 1, 2004
  7. Mar 1, 2004 #6

    marcus

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    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-----
     
  8. Mar 1, 2004 #7
    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!
     
    Last edited: Mar 1, 2004
  9. Mar 1, 2004 #8

    Nereid

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    ESO PR, which includes a link to the Pelló paper (near the bottom, cllick on "EDP web site")
     
  10. Mar 1, 2004 #9

    Nereid

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    Can you find Barcelona and Observatoire Midi-Pyrénées on this image?
     
  11. Mar 2, 2004 #10
    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...
     
  12. Mar 2, 2004 #11

    Nereid

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    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.
     
  13. Mar 2, 2004 #12
    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 web site you know of that explains this all for more common folk?

    Thanks!
     
  14. Mar 2, 2004 #13

    marcus

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    Re: Thanks!

    one strategy would be to stick with this web site and keep asking questions
    I did not see anyone here so far resent it if someone persists in asking about what he doesnt 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 wont 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)
     
    Last edited: Mar 2, 2004
  15. Mar 3, 2004 #14
    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.
     
  16. Mar 3, 2004 #15

    marcus

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    Re: Yes!

    you qualify all right:wink:
    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
     
  17. Mar 3, 2004 #16
    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
     
  18. Mar 3, 2004 #17

    marcus

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    Re: Genesis Galaxy...

    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.
     
  19. Mar 3, 2004 #18

    Nereid

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    Re: Thanks!

    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.
     
  20. Mar 3, 2004 #19
    Re: Re: Thanks!

    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.
     
    Last edited: May 2, 2004
  21. Mar 3, 2004 #20

    Nereid

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    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'.
    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.
     
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