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Galaxies Twice As Bright As Previously Thought

Posted by Soulskill on from the intergalactic-dust-buster dept.

Astronomers led by Simon Driver of Scotland's University of St. Andrews have discovered that interstellar dust shades us from as much as 50% of the light emitted by stars and galaxies. The scientists compared the number of galaxies we could see "edge-on" against the number which were "facing us," reasoning that dust would obscure more of the former, since we already receive less light from them. SPACE.com notes, "In fact, the researchers counted about 70 percent fewer edge-on galaxies than face-on galaxies." A NYTimes report provides some additional details: "Interstellar dust absorbs the visible light emitted by stars and then re-radiates it as infrared, or heat, radiation. But when astronomers measured this heat glow from distant galaxies, the dust appeared to be putting out more energy than the stars. 'You can't get more energy out than you put in, so we knew something was very wrong,' said Dr. Driver. The results also mean that there is about 20 percent more mass in stars than previously thought."

3 of 139 comments (clear)

  1. Re:So there's more dust than previously thought... by Vectronic · · Score: 3, Insightful

    "except to bend the light through gravitious pull"

    hence, "obscure" ... :P

  2. Tail wagging the dog... by msauve · · Score: 4, Insightful

    Science is about explaining observations (evidence) with testable theory, not claiming a theory to be evidence.

    The emperor has no clothes.

    --
    "National Security is the chief cause of national insecurity." - Celine's First Law
  3. Wrong... by msauve · · Score: 3, Insightful

    ...We know that dark matter can't be accounted for by large mass objects (like planets, asteroids, dust, etc) because CMB measurements tell us that the total amount of baryonic matter ('normal' matter made up of protons and neutrons) is a small fraction of the total matter
    What you mean to say is that the theory of life, the universe and everything which you subscribe to breaks if there is no exotic dark matter. There is no proven "upper limit on the amount of baryonic mass in the universe," there are only theories and hypothesis which make that claim as part of their model. I won't try and prove a negative by saying that theory is necessarily wrong, but the onus is on you to prove that portion of it correct by finding some of this imaginary non-baryonic mass. Myself, I'll claim that the Flying Spaghetti Monster plays with the gravitational "constant" to fool with us. Prove me wrong.

    Your circular logic fails to prove that dark matter exists.
    --
    "National Security is the chief cause of national insecurity." - Celine's First Law