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NASA

New Sharpened Images From Hubble Telescope Contradict Post-Big Bang Theories (nasa.gov) 98

An anonymous reader quotes NASA: By applying a new computational analysis to a galaxy magnified by a gravitational lens, astronomers have obtained images 10 times sharper than what Hubble could achieve on its own. The results show an edge-on disk galaxy studded with brilliant patches of newly formed stars... The galaxy in question is so far away that we see it as it appeared 11 billion years ago, only 2.7 billion years after the big bang... The resulting reconstructed image revealed two dozen clumps of newborn stars, each spanning about 200 to 300 light-years. This contradicted theories suggesting that star-forming regions in the distant, early universe were much larger, 3,000 light-years or more in size. "There are star-forming knots as far down in size as we can see," said doctoral student Traci Johnson of the University of Michigan, lead author of two of the three papers describing the research.
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New Sharpened Images From Hubble Telescope Contradict Post-Big Bang Theories

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  • starring Traci Johnson
  • How many cubic lightyears of stuff does it take to make a star? I'm not sure why this is surprising. Things were more compact back then, right? :)
    • by Anonymous Coward on Sunday July 09, 2017 @07:46PM (#54775711)

      Within a galaxy, things were not more compact then. On the largest (between galaxy clusters) scale, things were more compact, but within a galaxy orbital dynamics are more important than the primordial distribution. There is some difference expected in the appearance of individual galaxies, but the galaxies themselves weren't much smaller.

      The other thing you're confused about is the concept of "star-forming region". These are clouds of gas and dust (such as the "Pillars of creation [wikipedia.org]") dense enough to allow stars to form relatively rapidly. Within such clouds, dozens or hundreds of stars form. It's not one star per region.

      Because fewer stars had formed 10 billion years ago, it was expected that more gas and dust was available, leading to larger clouds.

    • For a cloud of gas to collapse into a star it has to have a certain mass in a given volume and be below a specific temperature. If the temperature is to high the heat will keep the cloud from collapsing. Clouds that can collapse into a single star are still rare. So you need a much much large cloud and hence you end up with star forming regions where the cloud collapses and as the density increases multiple stars are formed. (as a cloud collapses it heats up but the density increases so that the tempera
    • read this https://en.wikipedia.org/wiki/... [wikipedia.org] Things were warmer only 1 billion years after the big bang so the clouds to form a star forming rejoin should have been larger.
  • by Gravis Zero ( 934156 ) on Sunday July 09, 2017 @06:39PM (#54775447)

    the validity of images they are talking about should be questioned because to see that far the Hubble had to squint as hard as it could. ;)

    • by MangoCats ( 2757129 ) on Sunday July 09, 2017 @09:47PM (#54776139)

      I often wonder how accurate the estimates of the gravitational lensing effect are... I mean, I'm sure there are dozens of PhDs based on methods "to be sure within +/- BS" of what they are seeing, but there are enough variables and unknowns in these methods to easily have a "whoops, missed this one" moment, several times.

      • by Tablizer ( 95088 )

        here are enough variables and unknowns in these methods to easily have a "whoops...

        Researchers do have practice with similar reconstruction techniques. [uchicago.edu] In the linked case there are multiple projections of the same target with varying degrees of distortion, which narrows the range of possible of mistakes. Any proposed lens model used on such has to account for multiple (distorted) copies of the same object.

        Thus, they can re-use the model on single-copy distortions with some degree of confidence.

      • Maybe 18 months ago, they were able to accurately predict the lensing, even accounting for dark matter, and position themselves exactly right to intercept photons that were billions of years old.

        It's pretty good, actually.

  • The light spots look a little too clean and consistent to me. There's a lot of stretching of an already resolution-stretched area. To come out that clean is not realistic.

  • Interpolation is interpolation. Extrapolation is extrapolation. Calling it enhancement does not change the facts.

    You could "upscale" plain old DVD to 4K. It is not 10 times sharper than DVD.

    • You're right and that's exactly why this interesting. This is the equivalent of someone using a digital camera to record an image being enlarged by an external lens. The camera normally wouldn't have the resolution to resolve the image, but something else is enlarging the image for it.

      Same thing is happening here. Without gravitational lensing the image would take up, say 10x10 pixels on the Hubble CCD (total guess) and not be well resolved. But with gravitational lensing that image is now taking up 20x200

  • A sample size of ONE doesn't mean squat.

  • We obviously have to make educated hypothesis on the age of the universe, but I don't think anyone is surprised we got it wrong (or still have it wrong). In the famous words of Albert Einstein: "Only two things are infinite, the universe and human stupidity, and I'm not sure about the former."

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