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VLT Smashes Record of Farthest Known Galaxy

Posted by Hemos on from the smashing-the-records dept.

rduke15 writes "From this press release of the European Southern Observatory : 'Named Abell 1835 IR1916, the newly discovered galaxy [...] is located about 13,230 million light-years away. It is therefore seen at a time when the Universe was merely 470 million years young[...].' More details and pictures here."

4 of 39 comments (clear)

  1. Re:thousand million? by Sidoine · · Score: 5, Informative

    In fact in Europe 1 billion = 1 million millions while 1000 millions is 1 milliard.

  2. It give new meaning to... by SirTreveyan · · Score: 5, Funny

    a long time ago in a galaxy far far away...

    I know...but someone had to do it...

    --

    SELECT * FROM User WHERE Clue > 0

    0 rows returned

  3. It's expanding "Into" itself by rpresser · · Score: 5, Informative

    You can think of it (in mathematical terms) as a mapping of R^3 onto itself which expands distances.

    An analogy that may help:

    Take a circular rubber sheet. Draw some dots on it. Pull the sides of the rubber sheet and watch the dots separate.

    Now imagine your rubber sheet started out as an infinite plane: it is no more infinite after stretching than before, yet all distances have increased.

    Now generalize from an infinite plane to an infinite volume, and you should get the idea.

  4. Re:Only one line detection? by elliptical_boy · · Score: 5, Interesting

    I agree that only one line is suspicious. But the spectral energy distribution --- its optical and infrared colors --- argue pretty convincingly for its idenitification as a high-redshift galaxy (at least for me, as someone who's worked in this subject).

    Moreover, the authors argue in the paper that the object sits on the appropriate gravitational-lensing caustic for a redshift 9-10 object. I.e., if the galaxy in question---Abell 1835 IR1916 --- sits on at the right place relative to the foreground galaxy cluster (Abell 1835), the General Theory of Relativity says that the mass of the cluster should magnify the galaxy by 25 to 100x in brightness (one of the authors, J.-P. Kneib, is a world expert on gravitational lensing).

    Lastly, if the galaxy was at, say, z=2.7, and thus much closer---but consistent with the colors if the galaxy was full of dust---the line would have to be the forbidden doublet of singly-ionized oxygen at 372.62 and 372.89 nm. But this doublet would have been easily resolved by the high resolution of ISAAC, the infrared spectrograph on the VLT used by the authors, but not seen.

    BTW, probably not a quasar --- the IR (restframe UV) colors are too blue compared to the Sloan z=6 clusters.

    The thing that bothers me, though, is the the shape of the Ly-alpha line --- it's asymmetric in the wrong way (too sharp on the red side, too gaussian on the blue side) compared to the z=3 galaxies.

    Still need a lot more data, though --- both deeper NIR spectra to look for the continuum and mid-IR images (perhaps from the VLT, or Spitzer Space Telescope, or eventually the James Webb Space Telescope) to confirm the restframe optical colors.

    Cheers,
    Scott