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NASA Sees Glow of Universe's First Objects

Damek writes with news from NASA's Spitzer Space Telescope, which has captured light from what may have been the first glowing objects in the universe, light generated 14 billion years ago. From the article: "'We are pushing our telescopes to the limit and are tantalizingly close to getting a clear picture of the very first collections of objects,' said Dr. Alexander Kashlinsky... 'Whatever these objects are, they are intrinsically incredibly bright and very different from anything in existence today.' Astronomers believe the objects are either the first stars — humongous stars more than 1,000 times the mass of our sun — or voracious black holes that are consuming gas and spilling out tons of energy. If the objects are stars, then the observed clusters might be the first mini-galaxies..."

7 of 327 comments (clear)

  1. Looks like this is already being refuted by Anonymous Coward · · Score: 5, Informative

    by some more powerful equipment. From New Scientist Space: "Because Hubble's mirror is larger than Spitzer's, it turned up dwarf galaxies too faint for Spitzer to resolve. "Once we remove pixels in the Spitzer images corresponding to the locations of these galaxies, the background infrared light level mostly disappears," Cooray told New Scientist. 'We think, therefore, the infrared light seen in Spitzer images is mostly due to the faint infrared glow from these dwarf galaxies.'" The full article

    1. Re:Looks like this is already being refuted by khallow · · Score: 4, Informative

      I've looked over the EM/plasma theories before. The cosmological scale theories might have a grain of truth, but the Solar System scale theories (eg, that comets are highly charged objects) contradict both what we see and our models of electromagnitism. Comets formed from existing material. It's quite possible that pre-solar system collisions and supernova created the features seen in the above comet material. But it's not plausible to explain this with an exotic theory that has stable highly charged objects (immersed in the solar wind which would drain away the charge) and huge, unobserved voltage potentials (the Earth and Moon vary enough in their orbits that we should experience some of this phenomena, but we don't).

      And then there's the Stardust mission -- which when combined with the results of the Deep Impact mission indicate quite clearly that our early assumptions about comets were quite wrong. Scientists are now apparently trying to invent scenarios for how it could be that comets would contain exotic meteorite particles as well as particles that have clearly been formed under intense heat. Perhaps they should consider that these initial speculations were wrong in the first place. I doubt we'll see any such sanity though. More likely, we'll see additional new speculations to support the earlier unsupported speculations.

      No, this is relatively modest disagreement with the models of comets and their origins.

      We have already observed objects with enormous mass packed in a very small location. Maybe our "black hole" models of what happens when that much mass is packed into one place is inaccurate, but these objects do exist. And multi-dimensional models are one approach for understanding models involving forces other than gravity. For example, the first Kaluza-Klein model was a five dimensional model which was able to explain general relativity and the electromagnetic force. However, in the process it introduced a scalar field which we've never seen experimentally. So that likely indicates that the model is incorrect, but that's the only significant cost of the model. It otherwise models gravity and EM pretty well.
  2. Re:Please explain by Gospodin · · Score: 5, Informative

    A good way to think of it is to imagine us as living on the skin of a balloon as it is being blown up. You are moving away from every other point uniformly, but you aren't near the "edge".

    In more physics-friendly language, there are only two possibilities - either the universe is open or it's closed. If it's open, then it's infinite in all directions and there is no edge (we don't think this is the case, but it's still technically possible). If it's closed, then there simply is no edge because as you travel in any direction you curve around to head back where you came from.

    It might also help to realize that while the visible universe may be "only" 14 billion light years or so in radius, the longest dimension of a closed universe could be several times this number due to inflationary expansion. So we may not be seeing everything that's actually out there.

    --
    ...following the principles of Heisenburger's Uncertain Cat...
  3. Re:1000 Times the mass of the Sun? by neurostar · · Score: 4, Informative

    The Sun is a pretty small star compared to others...

    Right, but the 1000 times the mass would be a huge star. The most massive stars known today are on the order of 100 times the mass of our sun. So these might be stars that are ~10x larger than the largest currently observed stars.

  4. Re:Please explain by LionKimbro · · Score: 4, Informative

    Ah; Excellent question.

    If you look at the "known universe," it appears that we are in the exact middle, dead center, of the known universe.

    When we see the Cosmic Microwave Background Radiation, we are seeing "the edge" of the visible universe, that we can see.

    As you look further and further away from where we are, you see deeper and deeper into the past, until you see back as far as we can, where we see only the cosmic microwave background radiation, uniformly, like a sphere, in all directions.

    Most astrophysicists doubt that we are at the exact middle.

    The reason we can't see things beyond the visible universe, is simply because light hasn't existed long enough to get to us, from things that exist beyond the edge of our light cone of vision.

    Right? If light has only existed for, say, 14.7 billion light years, then you're not going to be seeing something that's 20 billion light years away. Or 100 billion light years away.

    It makes sense that, at the very edge of our vision, we see the genesis of the universe, in all directions.

    Astrophysicists today do not know how large the universe is, and it may well be infinite, in all directions. Astrophysicists take this idea very seriously, as far as I understand. That said, they also take seriously the idea that it is smaller than the observable universe, and just has a wrap-around effect.

  5. Re:Almost there... by MillionthMonkey · · Score: 5, Informative
    RTFA FIRST- in reality they're looking at stuff only 13.2 billion light years away, not 14 billion- which would indicate light that was older than the universe itself at 13.7 billion years old
    The actual horizon is 53 billion light years away, not 13.7. Consider a photon emitted very early, when the universe was still small, that reaches Earth today. During the first year of that photon's life, it would crossed only one light year of space on its trip to us- the first one.

    13.7 billion years later, that first light year has expanded like a rubber sheet to have a disproportionate contribution to the 53 billion, compared to light years that the photon covered later on, just before reaching us. You can't just multiply the total elapsed time by c. You have to actually do an integral over time for the entire trip to get the 53 billion, where the integrand is the product of c by the "stretch factor" S(t) at that point on the trip: the factor by which the space that a photon was flying through at time t has expanded by now (as considered relative to a frame where the Earth is at rest). I don't know what this function would be, but I do know it's a function of time (or more specifically, time since the Big Bang in a frame at rest with respect to the microwave background radiation).

    If S(t) were fixed at 1.0, you'd expect an integral of 13.7 billion light years. But it isn't fixed at 1.0; it is always greater than that and only approaches 1.0 at the end since light years at the end of the trip haven't had much time to expand. At the start of the trip S(t) could have been very high, depending on the age of the universe at the time.
  6. State of the Art by jd · · Score: 4, Informative
    The state of the art is that the Universe is a shape. That's about as much agreement as we're likely to see for some time. Current theories range from soccer-ball shape (which would explain the extreme uniformity of the microwave background radiation without needing Inflation Theory) to a strange 12-dimensional ultra-sausage (3 dimensions are circular, time is flatish, the other 8 are curled up to almost zero size - this gives us String Theory, one of the better bets for a Grand Unified Theory but difficult to prove and in definite violation of the Keep It Simple philosophy) to a perfectly normal sphere that expands indefinitely (currently the best explanation for the calculated value for the Hubble Constant) to a dimple that will expand into a flat plane (which is the best explanation for why none of the constants seem to be, well, constant).


    The current belief is that more than one of the theories is likely to be wrong, although it is entirely possible that they are all correct depending on the observer and/or universe. (In the Many Worlds theory, there is one instance of the Universe for every possible permutation of valid events that could ever occur. If this theory is correct and the shape of the Universe is dictated by events, then the shape of the Universe is determined by which branch you happen to be on at the time you do the observation. If branches can interact, this may vary between observations.)

    --
    It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)