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Interferometer Spots Galaxy at 40M Lightyears

Posted by michael on from the i-spy dept.

techno-vampire writes "JPL announces that a pair of telescopes used as an optical interferometer have detected a galaxy 40 million light years away, smashing the previous record of 3,000 light years. This feat, using infrared, has given us a far more detailed look into the center of a galaxy, and opened up a whole new field of research."

11 of 60 comments (clear)

  1. Hubble Deep Field Images? by orkysoft · · Score: 3, Interesting

    What about the Hubble Deep Field images that showed galaxies as much as 13 billion light years away?

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    I suffer from attention surplus disorder.
    1. Re:Hubble Deep Field Images? by orkysoft · · Score: 5, Informative
      NGC 4151 is 40 million light years from Earth, far beyond the most distant object previously detected by this type of telescope system, which was about 3,000 light years from Earth.

      Ah, that explains.

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      I suffer from attention surplus disorder.
    2. Re:Hubble Deep Field Images? by lookingup · · Score: 5, Informative

      The important point here is that they were able to use the two Keck "big guns" together to simulate the resolution of a much bigger telescope. Until recently, only bright stars were bright enough to make these sort of observations. The Keck and ESO interferometers are light-years ahead both because of their large mirrors and because they're using advanced image correction via small, flexible mirrors to correct for the distortion caused by our atmosphere. This makes the light train much more coherent and makes it much easier to get good interference patterns. Therefore they can observe much fainter objects.

    3. Re:Hubble Deep Field Images? by inertia187 · · Score: 2, Informative

      It's the deepest detection by interferometer. It's just a spot, though. Hubble's Deep Field images are more fun to look at. And with multiple passes, it's even pretty. These three have a lot to say about this subject.

      --
      A programmer is a machine for converting coffee into code.
  2. Read article, interferometer != telescope by Caractacus+Potts · · Score: 2, Interesting

    I wish I could tell you the difference between the two, but I'm just now looking it up myself. Obviously, we've "detected" objects much, much, much further away. Even more importantly, we even have "Artist's Depictions" of those too!

    1. Re:Read article, interferometer != telescope by hubie · · Score: 2, Interesting

      Keep in mind that a telescope really is an interferometer. It forms an image by combining light from all parts of the primary mirror in phase at the detector. A (two-beam) interferometer combines light from two beams in phase at the detector. You can easily convert a telescope from it's "normal" mode over to an interferometer by putting a mask with two holes on it. This is how Michelson made the first stellar diameter measurements, and the Kecks, operating in interferometer mode, are just using the same technique Michelson did, just on a much much larger scale.

  3. Re:40 million light years? by orkysoft · · Score: 2, Funny

    The galaxy in question is supposedly called the "Beowulf Cluster" ;-)

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    I suffer from attention surplus disorder.
  4. The Devil's in the DETAILS by Makoss · · Score: 4, Insightful

    To hopefully help quell the rush of prople who don't RTFA. Because the post is a bit. . .misleading.

    "NGC 4151 is 40 million light years from Earth, far beyond the most distant object previously detected by this type of telescope system, which was about 3,000 light years from Earth."

    "this type of telescope system"

    They are refering SPECIFICALLY to the technique used to image this. NOT 'most distant object imaged'.

    --
    Building a better backup.
    Zettabyte Storage
  5. Re:so... by Anonymous Coward · · Score: 2, Informative

    Everything in the universe is moving away from everything else. A "two-dimensional" model should help you get this.

    Imagine a balloon. Now, imagine dots on the outer surface of the balloon that represent galaxies and other matter. These objects exist on the two-dimensional plane that is the outer surface. It is curved slightly in three dimensions, but from the point of view of the dots, they don't notice this (they can't percieve this third dimension).

    Now, imagine if I blew the balloon up. The dots move away from each other and space expands between the dots. The balloon universe is expanding, but where is the center? There is no center.

    This holds true for our own universe. The universe is expanding in more than three dimensions. Basically, the space between the stars and galaxies is expanding. Therefore, there is no "center" of the universe.

  6. Just wait for another 10 years by Radical+Rad · · Score: 5, Interesting
    When the MAXIM flys in about another decade, it will be able to resolve images (in Xray) up to a million times better than anything now available. It will allow imaging of blackholes, that is actual visualization of the Shwarzchild radius as well as observing other stars as well as we can our own sun today. To do this the telescopes must be in orbit since the high frequency radiation scatters too easily in the atmosphere. Even at the infrared wavelengths that the Keck used, adaptive optics were needed to make their observations from the ground.

    I would like to see an array of cheap telescopes stationed at the LaGrangian points to do interferometry at any wavelength. Gravity wave detection could also be included in the mix. There would be no need for elaborate vibration damping and not being limited to the simple L shape that current ground based gravity detectors use, we would be able to triangulate gravity wave disturbances in 3 dimensions!

    ...I sense a change in the force...

  7. ?!? That ain't right. by voisine · · Score: 2, Insightful

    Our own milky way is about 100,000 light years across, so
    that 3,000 light year number is at least a few orders of
    magnitude off. WTF?