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Space Science

Interferometer Spots Galaxy at 40M Lightyears 60

Posted by michael 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."
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Interferometer Spots Galaxy at 40M Lightyears More

Interferometer Spots Galaxy at 40M Lightyears

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  • Hubble Deep Field Images? (Score:3, Interesting)

    by orkysoft ( 93727 ) <orkysoft@myMONET ... om minus painter> on Friday October 03, 2003 @09:50PM (#7129861) Journal
    What about the Hubble Deep Field images that showed galaxies as much as 13 billion light years away?

    • Re:Hubble Deep Field Images? (Score:5, Informative)

      by orkysoft ( 93727 ) <orkysoft@myMONET ... om minus painter> on Friday October 03, 2003 @09:54PM (#7129876) Journal
      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.

    • Re:Hubble Deep Field Images? (Score:5, Informative)

      by lookingup ( 563464 ) on Friday October 03, 2003 @09:59PM (#7129902) Homepage
      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.
    • 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 [blat.info] have a lot to say about this subject.

  • Read article, interferometer != telescope (Score:3, Interesting)

    by Caractacus Potts ( 74726 ) on Friday October 03, 2003 @09:57PM (#7129890)
    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" [hubblesite.org] of those too!
    • 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
  • I wonder if that's far enough to find the people who find overlords jokes funny.

  • The Devil's in the DETAILS (Score:4, Insightful)

    by Makoss ( 660100 ) on Friday October 03, 2003 @10:22PM (#7130034) Homepage
    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'.
  • Comment removed based on user account deletion
    • Not quite so simple.

      A more accurate representation is that space is expanding, thus every point it getting further from every other. So wherever you are everything seems to be moving away from you. . .

      I'd give more detail, but it's 8pm, on a friday night, and I'm still at work. It's time to be gone.
      • ...space was supposedly full before it started expanding. It has been cooling, in theory, because of the expansion of space itself rather than the expansion of matter within space.

    • Re:so... (Score:2, Informative)

      by Anonymous Coward
      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 aw

      • Re:so... (Score:1)

        by PD ( 9577 ) *
        The balloon is a bad example. Use the raisin bread instead.

        When you bake a raisin bread and it rises, all the raisins get farther apart from each other. Each raisin sees all the other raisins receeding from it.

        • When you bake a raisin bread and it rises, all the raisins get farther apart from each other. Each raisin sees all the other raisins receeding from it.

          Yes, but a loaf of bread has a definite center. The surface of a balloon doesn't. Ignoring discontinuity at the neck of the balloon, every spot on the balloon's surface has equal claim to be the center, which makes it a better analogy in this case.

          In the real Universe of course, I'm the center. :-)

      • The balloon universe is expanding, but where is the center? There is no center.

        Not far from us, it turns out. The galaxies in our universe are arranged, loosely, in concentric shells. The center about which these shells are con happens to be not far outside our own galaxy.

        Lots of scientists pooh-pooh the idea, not because they've examined the data but because they're allergic to the philosophical implications of this. A few others have made genuine attempts to examine and refute the data, so far withou

        • And the evidence for this is ....?
        • offhand i'd say we've been Trolled. Maps of galaxies, generally thin wedges, show them to be arranged as filaments or sheets around the edges of voids, for example this [nasa.gov] and a higher res version [nasa.gov]. The galaxies are not arranged as concentric shells but as the matrix of an open-celled foam. Any appearance of concentricity is due to the fact that galaxies further away are harder to see [anzwers.org] (see the bottom image).
          • A chap named Halton Arp started making a collection a peculiar galaxies [3towers.com] which seemed to be (and still are) doing bizarre things to our notions about redshift, eventually building his collection to 338 entities (if you follow the links on that page you can see images of every one of them).

            One of the things he noticed was that galaxies happen in statistically significant concentric shells, at least according to the redshifts. One of the less heated discussions I've seen of the consequences is at the Universi [ua.edu]

            • I was hoping for "links to concentric galaxy stuff." Instead it is a discussion of non-cosmological redshift, which is a related topic but not quite what I was hoping for. According to hubblesite.org, "Only a few astronomers still think there is reasonable evidence for noncosmological redshifts," and "An overwhelming abundance of evidence long ago convinced virtually all astronomers that quasars are indeed at the vast distances indicated by their redshifts." Much of this shift in view comes from Hubble's
              • ...from RGB photos instead of spectral lines on a plate.

                Like I said, many scientists object to it from their armchairs (and others too, QED) more because they're uncomfortable with where it might take them than by experimenting themselves or because they've found positive contradictions. Vague handwaving appeals to authority like the HubbleSite wording are almost a hallmark of this approach.
                • "from RGB photos instead of spectral lines on a plate."

                  Yeah, exactly, so why did you supply the link to the photos of the Arp collection of peculiar galaxies? You originally were arguing about concentric shells of galaxies. That's what I'm curious about, and because you are too reticent to post an appropriate link, I still know nothing about this theory.

                  And the hubblesite quotes were taken from a page [stsci.edu] quite relevant to the Arp galaxies. The famous Markarian 205 photos showing a purported link between a

                  • There are plenty of spectra elsewhere - and perhaps more usefully, plenty of tabulations and analyses of said spectra.

                    Also, there is nothing to stop Markarian 205's quasar from being behind the "host" galaxy relative to us, since we are working in 3D here. The unsolved question is how far behind it is. It doesn't make much weight in the argument either way, but if you could show that every case was such an overlay and that there were few cases of near-UV absorption for visually isolated quasars you'd have
                    • Also, there is nothing to stop Markarian 205's quasar from being behind the "host" galaxy relative to us, since we are working in 3D here."

                      No. NGC 4319 has been disrupted by gravitational forces from something massive, as evidenced by the wide flung arms and the dust lanes. These are roughly perpendicular to our line of sight, meaning the galaxy and the massive object are also in a plane perpendicular to our line of sight. Many members of your wacky little group thinks it's the Seyfert, Markarian 205,

                    • No. NGC 4319 has been disrupted by gravitational forces from something massive, as evidenced by the wide flung arms and the dust lanes.

                      Yes, and what does it look like from the side? You've got to admit than an exactly-planar strike is extremely unlikely - unless Arp's theories on the issue are in essence correct (obviously not a palatable outcome for you).

                      Any proof that the Seyfert is not in the plane is proof against this theory.

                      Why? A few thousand or tens of thousands of light-years may not make

                    • Our discussion started with name calling and has gotten worse. I'd prefer to see if we can agree on who believes what and why. The issue is very complicated, so I'm attempting to separate put the numerous theories into a small number of camps.

                      Camp 1: Support the work of William Tifft in '70s, and subsequent work of Napier and Guthrie in '97 showing quantized redshifts, used as proof of geocentric or galactocentric universe, with concentric shells of galaxies around us or our galaxy. Tifft's early work

                    • I'm happy here in the peanut gallery, noting that several cosmologists are grossy upset at the existing theories (I note the recent appearance of another new "white-hole cosmology", for example) and waiting to see how the dust will settle.

                      But meanwhile, please accept a "+1, Reasonable" moderation for your response. (-:
      • There's one thing that I've always wondered about - Does that mean that we are expanding along with it?

        Is the earth further away from the sun than it used to be? So the dot on the ballon that represents the Earth and the dot for the sun are further apart?

    • From things I've read, everything in the universe seems to be moving away from something and expanding. So, where is the "center", what's in it?

      There is no center. Space is either infinite (open universe) or finite (closed universe). If space is infinite, then there is no center because there is no boundary. On the other hand, if space is finite, then the curvature of space means that the universe eventually closes back on itself at some unimaginably distant distance.

      In one case it's like asking "

      • IANA celestial physicist but from what I understand, the definition of open and closed universe is not refering to a boundry, or infinite space. From what I've read, there is a finite amount of "space" (not to mention matter) regardless of open or closed.
        Here's my breakdown:
        The universe was born around 15 billion years ago and it's been expanding ever since. Whether it continues to expand depends on the amount of matter in the universe. If there is not enough matter (i.e. not enough gravity), the univer

        • the definition of open and closed universe is not refering to a boundry, or infinite space. [snip] If there is not enough matter (i.e. not enough gravity), the universe will continue expanding at an accelerated rate [snip] The third option, you didn't mention, is where scientists think we are now....a 'flat' universe.

          OK, I was speaking imprecisely. You're partly correct. A closed universe is often used to mean a universe that will eventually collapse upon itself.

          In all cases, there is (at any m

  • Just wait for another 10 years (Score:5, Interesting)

    by Radical Rad ( 138892 ) on Saturday October 04, 2003 @12:11AM (#7130501) Homepage
    When the MAXIM [nasa.gov] flys in about another decade, it will be able to resolve images (in Xray) up to a million times better [spaceflightnow.com] 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...

  • ?!? That ain't right. (Score:2, Insightful)

    by voisine ( 153062 )
    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?
    • Probably some sort of Einsteiniean relativity whatchamagig.

      Or maybe we're just hosting some really small gallaxies inside our own....

      Or maybe it's a case for a fractal universe...

      or maybe I just need to go to bed (1am here)

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