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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..."
Once the have a telescope that can peer past that glow, they find the number "42" at one of the cosmos and a hitchhiker thumb at the other end.
Focusing on glowing objects...
"Ahhhh, I can see what it says!"
"What is it?"
"Its a sign of some kind!"
"A sign?, what does it say?"
"Look out behind you!"
liqbase
Since when is a star of 1000 times the mass of the Sun a humungous star? The Sun is a pretty small star compared to others...
I suffer from attention surplus disorder.
... 'cause 14 billion years is about as old as news can get. Literally.
Thank you, I'll be here all week, enjoy the sushi!
Stressed? Me? Of course not. Stress is what a rubber band feels before it breaks, silly.
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
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...
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.
I don't understand how even if we are on opposite sides of this expanding balloon (or whatever other expansion analogy you want to pick) how this can exceed the speed of light. I can't see another way for light from the birth of our universe to reach us only now.
*thinks about it more*
Nope, doesn't make sense to me.
Technically, you could triangulate the origin of the light by using two separate cameras. From that distance calculation you do the math. We know the speed of light (Roughly 300 MegaMeters Per Second), from this we know the distance light travels in one year (A Light Year - Measurement of Distance, not time). So, we could figure out that a source of light is 14 Billion Light Years Away, Which also tells us that the Light originated 14 Billion Years ago.
The error margin is low, based on our ability to accurately determine the wavelength of the radiation in question (I'm pretty sure it's awfully accurate). It was described to me this way (from Trefil's Reading the Mind of God): We are able to recreate in laboratories the conditions in the universe to within 10e-33 seconds of the Big Bang. Therefore, we know the exact temperature of the radiation emitted from the Big Bang. Assuming no other variables which could increase the temperature of the background radiation and knowing the current wavelength of the background radiation around us (it's in the Microwave range), we can tell the light is 14 billion years old by its wavelength. I hope I didn't screw that up :)
mandelbr0t
"Please describe the scientific nature of the 'whammy'" - Agent Scully
OK. Been meaning to have this conversation with someone in the know, but I'll have to make do with slashdotters (I keed, I keed!)
I understand what you are saying, mostly. But, define this concept of infinite space. To me, anything that exists 3 dimensionally must have physical measurements, and thusly, a point in which it ceases to geographically exist. Saying the universie is infinite seems (respectfully, I'm not trying to troll here) like trying to finish that science paper early so you can go to sleep. Plus, the theory that the universe is expanding, to me, immediately brings to mind that it is going from a smaller size to a larger size, in which case, the previous argument begs more attention. I always try to imagine, or ask myself, what is beyond the universe.
That's usually about the point I go crosseyed, say to hell with it, and go play video games.
Raging in an online forum won't do anything for the world around you. To see change, you must take action.
Obviously. If you go back far enough in time, of course you'll see the glow from when the dimmer switch is just being turned up. I can't believe we waste perfectly good Science Money on wacky alternative theories, when the EUDS explains this perfectly.
Don't disappoint your bird dog. Go to the range.
Cool!
The journal articles that go along with the story:
New Measurements of Cosmic Infrared Background Fluctuations from Early Epochs
On the Nature of the Sources of the Cosmic Infrared Background
(These were posted in the article, but only under a tiny "More info" link at the bottom that is easy to overlook.)
And before anyone jumps in about this :-) ... The universe can do this without violating known laws of physics because it's not really the boundaries of the universe that is "moving" in the normal sense, see also here: http://en.wikipedia.org/wiki/Metric_expansion_of_s pace
Beware: In C++, your friends can see your privates!
You can read the technical papers on which this press release is based:
http://arxiv.org/abs/astro-ph/0612445
http://arxiv.org/abs/astro-ph/0612447
The basic idea is that the astronomers used an infrared
space telescope to take very deep images. They then tried
to remove all the obvious sources of light, and examined
the resulting "blank" images very carefully. They claim that
there are very faint sources of infrared radiation which
remain, and that the spatial correlation of these sources
is roughly what one would expect if they were young galaxies
in the very early universe.
There are limited opportunities for other astronomers
to examine the same regions with other telescopes and
at other wavelengths; that could provide evidence that
might support the claim, or weaken it (if, for example,
radio telescopes detect some of these sources and
show that they are ordinary galaxies in the relatively
nearby universe, that would weaken the claim in
the press release).
We can also just wait a decade or so for JWST, a more
powerful infrared space telescope, to observe the same
field.
Michael Richmond "This is the heart that broke my finger."
mwrsps@rit.edu http://stupendous.rit.edu
Alternatively, I think that it doesn't make much sense to think about space in terms of space. That's kind of like thinking of lollipops in terms of lollipops. I mean, sure, they're delicious. If I tell you about lollipops, you may think, "Mmm, those are delicious." But I don't know that I could say anything useful to you about lollipops strictly in the language of lollipops, whatever that means. Frankly, there's a lot of ways to mess with space (dilation, anyone?), and it doesn't seem as static a thing as I once thought it was. What happens when you stretch out space? Hmmm, more space.
My gut intuition (not that it means much) makes me think that the universe is closed and probably looped back into itself. The main reason is that it seems like a weird concept to have space just "end". If it were shaped like a balloon, for instance, maybe there's a way to avoid some disturbing delta functions of vacuum to nothingness.
Oh yeah, sorry I couldn't help. I'm done rambling now.
Think of it as the difference between how fast an ant can crawl across the surface of an expanding balloon, vs. how fast the balloon itself is being inflated. The two speeds are not related to each other, and there can be a limit on the former when there is not on the latter.
This might help you understand what people generally mean. ( I might be totally wrong here, so anyone more knowledgeable feel free to correct me. )
You talk about a thing that exists 3-dimensionally needing to be measured. That's fine for a thing, but space is not a thing. Space sort of *is* the measure of things. If you imagine an x-y-z axis, space *is* that axis. And in the case of infinite space, those axes go on forever. Space is not a thing; it's the, uh, space in which things exist. It's just the distance between things. It's abstract -- not really a thing, but the relationship between things.
Maybe reading some philosophy or metaphysics about 'space' would help you understand, rather than physics that already assume you understand the concept.
Computers are useless. They can only give you answers.
-- Pablo Picasso
I found this hard to visualise until I realised that dodecahedrons tessellate perfectly in 3D space. So just picture a bunch of glass dodecahedrons stacked together with invisible seams, stretching to infinity, except there's only really 1 of them, and the rest are just reflections.
*If* the universe is closed like this, it *could* be a lot smaller than it looks. We'd only know for sure if we could see a few more Milky Way's (or some other obvious structure) in our vicinity.
09F91102 no, 455FE104 nope, F190A1E8 uh-uh, 7A5F8A09 that's not it, C87294CE no. Ah! 452F6E403CDF10714E41DFAA257D313F.
Keep in mind that my understanding is that of a lay person keeping track of things by wikipedia, and occasional conversation with live scientist. But here's what I understand, so far.
Space is expanding, but it's expanding in the sense that the distance between galaxies is growing larger. Not that it's expanding out "into" something, or anything like that.
Imagine an infinite universe, existing in all directions, filled with galaxies.
Now, take the same space, but multiplying all (x,y,z) coordinates by, say, 1.2. (Note that, this transformation works the same, regardless of where you pick your origin!)
Now, the various forces hold atoms and planets and stars and galaxies together, so the galaxies, stars, planets, people, plants, themselves, don't get bigger. Only the space between galaxies.
This is a model of an expanding, infinite universe. It would have no "edge," it would just keep going.
The objects in the infinite universe have finite dimensions. But the space itself, may be infinite. Again, we don't know, but it's a possibility.
I ask myself: "Did the big bang necessarily occur out of a single point?" Because, you can have incredible densities, and a "bang" (by expanding universe,) but not necessarily have everything coming out of a single point. Mathematically, too, you can actually map all of the Real numbers, 1:1, in the space between 0.0 through 1.0. "Is it possible that the universe began with super-high density, in all directions?" I need to ask an astrophysicist this question, don't take my thoughts on this one.
It's a very long series of conjectures basically. You measure the redshifts from known close star and "fixed" stars (star that don't appear to move). You come up with a series of ratios, you interpolate the distance based on redshift.
I am simplifying vastly here but you get the gist. It's about measuring close things and then using what you know about them to measure far things.
evil is as evil does
the speed of light is thought to be decreasing
Thought by whom?
That would imply that our matter had exceeded the speed of light to arrive here.
Essentialy, it has
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)
I've never understood this. If light from the beginning of the universe started traveling at the speed of light 14 billion years ago, how can we be out ahead of it to see it? At what point did the particles that became us move out from the beginning of the universe faster than light, so we can now turn back to the direction from which we came and see what should be very far ahead of us. No this is not a troll. It's a real question. Thanks in advance.
San Francisco Photographers
Do not stare into universe with remaining eye.
"Let's face it, it's a good story. Accuracy would kill it."
If light existed only for 14.7 billion years, then objects couldn't be farther than 14.7 billion light years, in fact, much less. As the maximum speed they could have (relative to us) is the speed of light.
No; There's no reason to believe things didn't start beyond us. Furthermore, there is the expansion of space.
That is, at the time of the big bang, my understanding is that there may have been plasma that was billions of light years away. My understanding is that the big bang refers to initial density, and to expansion. But not necessarily to a beginning in a single point.
In my defense, I refer you to a NASA site, "WMAP Cosmology 101," the part that begins with: "Please avoid the following common misconceptions about the Big Bang and expansion..."
Everyone knows the universe is only 6,000 years old.
Ah shit, the salesman said the trilobite fossil was 7,000. I want my money back.
Table-ized A.I.
Matter falling into the black hole, before it reaches the event horizon, gains an immense amount of energy in the falling in, and reradiates some of it. Also, black holes do evaporate through quantum tunneling (which is why there aren't any small ones around - they go BOOM that way).
mark
We can't observe the hole itself but we can observe the effect it has on matter that hasn't fallen into it's event horizon. Matter will not fall straight into a hole; it will spiral in. As it is spiraling in, it will emit X-rays as a sort of death cry. Also black holes have magnetic fields and spin. A black hole actively feeding will ionize matter and some of this charged matter can be caught in the holes magnetic field and ejected from its poles as bright jets. It is a misconception to think of a black hole as a sort of cosmic vacuum cleaner that will suck down everything. A black hole has no more gravity than the mass that gave birth to it. A black hole can be safely orbited for instance. But the mass of a hole is so intensely concentrated that very exotic tidal effects are caused closer in to the hole. Get too close and yes even light will not escape. Get almost too close and very very weird (but predictable and observable) things happen.
Since there can never truly be such a thing as a true vacuum black holes can even evaporate. Since absolute zero can only be approached (but never reached) any given volume of space has a quantity of energy available within it. This energy can give rise to pairs of particles once thresholds are reached. The particles are formed in pairs because properties like spin and charge are conserved. This matter does not come from nothing! It is formed at the expense of available energy in the vicinity. If a pair of particles forms in the vicinity of a black hole's event horizon then one of the pair can fall into the hole while the other sluggishly makes it's way away from the hole. This happens at the expense of the energy of the hole itself so if the black hole isn't being fed with other sources then it will shrink a trifle. Large black holes have event horizons that appear barely curved at subatomic scales; this means that large black holes lose mass very slowly in this way. Even a hole with a few times the sun's mass will last far longer than the universe has existed to date. Smaller holes have more curvature on local scales and lose energy very very quickly. This is why the prospect of forming a hole in a particle accelerator isn't particularly scary.