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The 1st Generation of Stars
Andy_Howell writes "Astronomers may have found members of the first generation of stars in the universe. Using the Hubble Space Telescope and the Keck I telescope, they observed a faint red blob that had been magnified into a double image by a gravitational lens. The blob was found to be a cluster of stars 13.6 billion light years away, seen when the age of the universe was less than a billion years old. The clump appears to contain only about a million stars, and is less than a few million years old. It is thought that swarms of these clumps came together over the age of the universe to create the galaxies we see today."
...that this article did not mention the Big Bang.
If you are interested there is a spectacular book entitled _The_Big_Bang_Never_Happened_ that describes an alternate (and far more rational) cosmology...it posits that the universe is ruled by elecromagnetically active plasmas, and that the behaviors of our universe need not be explained by increasingly unlikely constructions.
Writers imply. Readers infer.
What if the universe were to wrap around itself, and we were actually staring at our backs? If there were some ultra-ultra-mega-super-densely packed gravity well or something in the center of our universe, we'd be going, "Man..thats an old ass.." but we'd be staring at our own and stuff.
Job? I don't have time to get a job! Who will sit around and bitch about being broke and unemployed then?
U GOTS TO B KIDDING ME..........BRITNEY SPEARS IS LIKE THE FIRST AND BESTEST EVER ... THERE AINT NO STARS B4 HER IN MY BOOK!!!!!!!!!!!! I LUV BILLY!!!!!!!
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The blob was found to be a cluster of stars 13.6 billion light years away, seen when the age of the universe was less than a billion years old.
Perhaps I've been out of touch with my astronomy studies for too long, I know there are a lot of discoveries being made. However I was under the impression that there was still a great deal of uncertainty about the age of the universe. It was generally agreed that it was somewhere between about 13 billion and 20 billion years old but exactly how old wasn't/isn't clear.
Is there something I don't know about or is this age prediction just an assumption? Have there been some consensus on this recently that I didn't hear about? Anyone know for sure? I'm always suspicious when I see "discoveries" like this whose results depend on something that hasn't been definitely proven.
Because it's not relative *constant* motion. Reputedly, due to the expansion of the universe, things father away appear to be moving away from use faster than things closer to us. This also means the light itself is being expaned -- shifted towards the red.
Go not to the Elves for counsel, for they will say both no and yes
Is there any application for this kind of astronomy?
If I were a director of federal astronomy I would enthusiastically fund near-galactic research that searched for wormholes, civilizations, planets that could support life, etc -- any kind of knowledge we need for a feasible star economy.
Basic science is nice, but erstwhile star captains probably wouldn't find the universe's origins very relevant.
Goat sex free since 2001
The blob was found to be a cluster of stars 13.6 billion light years away, seen when the age of the universe was less than a billion years old.
How is this possible? When the universe was less than a billion years old, then any two particles in it would have to be within two billion light years of each other, assuming the "big bang" model is true. It could not take light from one of them 13.6 billion years to reach the other.
What's wrong with my reasoning?
Each dot on that image is a galaxy/star/something. The color of the dot is what's interesting -- the redder it is, typically the further away it is. If you look at the big image, there are a lot of dots, but they're only slightly reddish. The two "interesting" ones are extremely red, indicating that they're very far away. Astronomers have shown that, since the universe is expanding, things further away from us are moving away from us faster and faster. The end result is that the doppler shift caused towards the red end of the spectrum gives us a quick indication of how old things are, and hence, how interesting they might be.
Is your boss an astronomer or something? Or are you just finding yourself strangely attracted to men with big telescopes?
It is by observing the doplar shift, or "red shift", in the wavelength of a stars light that the length to almost every distant object is measured.
Think of yourself as being on the surface of an expanding baloon: relative to other objects that are close to you on the surface, you are moving very slowly. Relative to objects at the center of the baloon or halfway around the surface, you are moving a little faster (remember this is as the crow flies). Relative to objects clear on the other side of the baloon, you are moving the fastest of all.
On the scale of the universe, objects on the other side of the galaxy are moving extremely fast (relative to you). I'm not sure exactly how fast, but I remember reading somewhere that it is getting close to the speed of light (after all, they have had to cover a huge amount of space to get so far away). This is easily fast enough to have an affect on the wavelength of the light - even a small relative speed will have a small (but probably unmeasurable affect).
IANAAstroPhysicist, so whether this explains the visibly red shift (since scientific spectrographs are much more sensitive than our eyes ), I cannot say. Another explaination might be that the stars are young and therefore cool, but I couldn't say that for sure either.
I don't recall the actual length of visible light waves, but I think it's in non-microscopic units. At extreme distances, the expansion of the universe probably means our relative speed to those objects is extremely high. What we see as the red light may have started in the ultraviolet at the source . . .
Am I the only one who finds Gravitational Lenses to be kind of creepy? Photons leave a star on different paths, eventually become separated by many thousands of light years so that entire galaxies separate them, then get deflected so that they eventually converge to within inches of each other just as they hit the surface of planet earth. Those are are some tall odds.
The other question is if we are peeking over into the backyard of the next universe over, where stars may be burning out. [smile]
but seriously, all of the stars of about the same age. and there is some red shift going on there.
But they may just be sufficiently small that they never reach bright blue. They may be just big enough to for the reactions to catch, without blowing them apart. and wind up being red.
"It is a greater offense to steal men's labor, than their clothes"
Maybe this is a stupid question but...
How does a galaxy cluster bend light that started out before the galaxies were born?
I'm assuming that the light from the 13 billion year-old stars is travelling at light speed and that the galaxy cluster lenses are younger than 13 billion years. So how does the lens get ahead of the light and bend it? Has the light has been slowed down?
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You cannot wash away blood with blood
In a later press release the scientist were quoted as saying, "Ooops! We thought we saw starts BILLIONS of miles away that had been magnified through a gravitational lense, but what we actually saw were some stains from an interns habit of dribbling coffee."
Excuse my cynicism (and my poor spelling), but they're trying to tell us that they're capturing light that was generated billions of years ago. Enough light to charge an optical receiver. I'm currently working on a project that has to generate laser light down a fiber, and pick up the signal after on a few miles, and we're having problems doing that. Occam's Razor applies here, and in my mind there are a mountain of explanations that fit better. Simple noise would be the first one. A body that is much closer but shrouded by some sort of haze is another. Even if space were nearly completely empty, wouldn't there be enough dust after a few zillion miles to make it opaque.
Just how much can we trust people claiming to see ghost (things that may very well be there, but no one else can see them)?
Aah, change is good. -- Rafiki
Yeah, but it ain't easy. -- Simba
"It is a profound and necessary truth that the deep things in science are not found because they are useful; they are found because it was possible to find them." -Robert Oppenheimer
Robert Moody from the Department Mathematical Sciences, University of Alberta illustrates the importance of curiosity based research in his paper using lasers as an example of why curiosity based research is necessary.
Carl Sagan in his book, The Demon Haunted World, also stresses the importance of curiosity based research using James Clark Maxell's discoveries as an example of how it effects our lives today by providing the necessary building blocks for radio, television, computers, lasers, etc.
Basic science is nice, but erstwhile star captains probably wouldn't find the universe's origins very relevant.
It may not seem very relivant at first, but there are those who would argue in order to even begin to piece together data for a theory of everything (which may be vital to even approach the idea of star captains), we need to gather as much data as possible to reduce our error bars of knowledge.
All in all, Good question... I'm sure some of you have better answers...
"Communism is like having one [local] phone company " - Lenny Bruce
A trivia point, for those interested. Helium was named for the sun, helios, first discovered when spectroscopy was very young. This element was not yet discovered on the earth and was thought only to be a "heavenly" element. That is until some researcher was told that if a piece of pitchblende was placed underwater, bubbles would form. He collected these gas bubbles in an inverted flask and analyzed them with the new spectroscope and found it to be helium.
Helium today mostly comes from mines. They are called mines and not wells because they produce a mineral but are essentially just like natural gas wells. This gas comes from radioactive decay which produces alpha particles---helium ions---which then capture electrons from its surrounding and becomes helium gas.
The stars WERE hot and blue when the emitted
the light we are now seeing; if you had looked
at the spectrum of the starlight back then
(because you were floating in space close to
the stars), it would have peaked in the
ultraviolet.
However, the light has travelled a long way
to reach us, and the universe has been expanding
since then. The redshift of these objects is
around z=5.58, which means that we observe photons
to have a wavelength (z+1) = 6.58 times longer
than their rest wavelength. The peak of the
spectrum has moved from the near UV to the near
infrared. Hence, the stars would appear red
if viewed by a person.
The pictures were formed by combining images
taken through several different filters with
HST. Each filter was in the visible range.
The astronomers who made the picture set the
Red plane of the image to correspond to the
picture taken in the reddest filter,
the Green plane to the filter of intermediate
wavelength, and the Blue plane to the bluest
filter. It's false color, but reasonably
like a person would see.
Michael Richmond "This is the heart that broke my finger."
mwrsps@rit.edu http://stupendous.rit.edu
Great photo!! (Be sure to click on it to see the higher-res copy.)
It amazes me that there are so many galaxies that each of us could own one. If we each owned a galaxy, then each of us would own more stars than there are people on Earth.
There's plenty of energy in the universe, it's just not always where you need it.
ABC News article: "Abu Sayyaf
Bush's education improvements were
Most astronomers had previously ignored these stars, which had been modded down heavily for posting annoying "First star!" messages.
When all you have is a hammer, everything looks like a skull.
Strom Thurmond.
In Soviet Russia, Chuck Norris will still kick your ass.
The problem with "The Big Bang Never Happened" (which I have read) and other alternative cosmologies is that they don't even attempt to go deep enough to prove their points. There's a reason for this. All of modern cosmology is based on General Relativity. If you are going to say that the Big Bang Never Happened, then your alternative cosmology has to not only come up with an alternative explanation for the Universe, but also explain everything that GR does without having a Big Bang. This is a very tall order.
It isn't enough to point out the contradictions in the standard model. It is also necessary to build a new model that explains all observations. To date, no one has been able to do this without having a Big Bang at the start.
A well-crafted lie appears unquestionable - Dama Mahaleo
No, I think you'll find those stars are actualy quite hot. Well, were. I guess they're cool -now-.
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)
Thank you. It's been awhile. I think I was thinking about sound waves and light waves at the same time. Audible sound waves (at least the bass ones, which are all I care about) are all in feet and inches . . .
No, we have a small number of poorly designed studies that seem to show that prayer unknown to the patient has an impact, and a number of better-designed studies that show no such thing. Every major "double-blind" study which has shown an effect from prayer on healing has later turned out to be unblinded indeed, with the personnel conducting the study having discarded evidence which didn't fit their hypotheses. Irwin Tessman, among others, has shown this quite thoroughly.
As far as the subject of this article goes: astronomers (and biologists, and geologists) are under no more obligation to consider the beliefs of creationists than historians are to consider the beliefs of Holocaust-deniers, or geographers are to consider the beliefs of the Flat Earth Society.
The correlation between ignorance of statistics and using "correlation is not causation" as an argument is close to 1.
Anyhow, assuming you're serious:
- Try radio astronomy data. For example, pulsar searches (related to what I do, forgive my bias) use simple time series data I(t) which would seem to be ideal for your work. Try this:
http://www.atnf.csiro.au/research/pulsar/pmsurv/
- HST data is always available for download,
once the proprietary period has expired, from the HST archive.
You don't care what the data is from, right? Note, though, that this is a 2-dimensional image, so it might have some "fake" compressibility due to redundant information. Radio data does not have this weakness, so I recommend that instead.
- For most astronomy data, you'll need to learn to read FITS format: try this.
Hope this helps - if you're serious and need help, feel free to drop me a note. (shami at astro dot cornell dot edu)"I will take the Ring," he said, "though I do not know the way."
Don't forget that the image is actually a visual representation of extremely complex data. Those "little red dots" are just the result of reducing the usefulness of the information to create something pretty to look at. The signifigant parts of the image are picked out by computer algorithms specifically designed to pick out the signifigant parts. Eyeballing it just doesn't cut it.
No. but they found the progenitor Twinkie molecules...
It doesn't mean much now, it's built for the future.
Hello? See the adequacy.org link in the .sig? Don't feed the trolls.
"The question of whether a computer can think is no more interesting than that of whether a submarine can swim" -EWD
In the first stage you have some phenomena that you want to try to 'explain' (in scientific parlance 'explain' actually means 'predict through use of appropriate mathematical formulae). The scientists will come up with hypotheses that yield testable formulae for predicting the phenomena in question.
In the second stage you gather lots of empirical data and see if the predictions of your hypotheses agree with the data you have gathered. You may gather data specifically chosen to prove your hypotheses false (since it should be easy to predict what measurements are most likely to disagree with your hypotheses) or you may just use whatever data comes easily to hand (there may be a large mass of existing data, as with Tyco Brahe's astronomical measurements used by Kepler to derive the shapes of the planets' orbits).
Once you have gathered enough data you can see where your hypotheses disagree with the measured data and adjust the hypotheses accordingly. Eventually your hypotheses agree to the measured data to within the current error bounds, at which time you have an official theory.
Importantly, you never actually have access to truth. Nothing is ever proven (though many things may be disproven) and everything is open to some level of doubt. It's just a matter of how much doubt you find acceptable for any give application. For common, everyday tasks, the precision required of most measurements is very low:
- speed of light = faster than anything else
- speed of sound = not as fast as light but faster than most other things
- age of the universe = age of the earth = older than we care to think about
- mass of a subatomic particle = as close to zero as makes no odds.
For specific applications you will require greater precision, but still not perfect precision:The real problem with your use of the terms 'truth' and 'proof' is that they don't mean the same thing to a scientist as they mean in common english. In common english Truth is absolute and Proof is irrefutable. To a scientist, however, truth simply means that the formulae yield answers close enough to measured values that we can't tell the difference (modulo the accuracy of our measuring devices), and proof simply means that no data has been found that clearly contradicts a specific set of formulae (aka, an hypothesis).
Just because science isn't accessing some cosmic Truth doesn't mean that sceintific theories are really just opinions. An opinion is a though in someone's head that has no concrete basis in fact. A scientific theory, on the other hand, is a set of formulae that serve to predict objective, measurable values for physical phenomena to within some specified error range. It may not be too similar to what most people think of as Truth, but it is pretty far from the common definition of option as well. It is certainly a damn sight more reliable that the assorted forms of propaganda, superstition, and outright ignorance that have passed themselves off as Truth for most of history.
It's probably the case that these are very hot stars with peak emission at blue or uv wavelengths. The reason for the red color is probably almost entirely due to the red shift of the objects, and possibly a small amount of interstellar dust (depending on how much intervening dust there is).
More often you see H-alpha emission from the gas clouds surrounding newly formed stars in star forming regions and such, it's somewhat rare (although not unheard of) to see strong hydrogen emission in a stellar atmosphere.
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D'oh! Had reddening on the brain, and the word "red" came out instead of "blue". :-)= Thanks for noticing that oops.
;-)
If only we were talking about X-rays, what I wrote would have actually been right.
[TMB]
Bingo! The article mentioned that this star cluster was found at a redshift of z=5.58 I believe. The formula of interest here is that
1+z=(Lamda_em - Lamda_ob)/Lamda_ob
This means that the light we observe from this star cluster is arriving at a bit less than a quarter of its original wavelength -- the red light seem in the picture was emitted as hard ultraviolet radiation from young massive stars! Yes, young stars are really hot.
If you think that's impressive, consider the quasars the Sloan Digital Sky Survey keeps finding out at z>6. We see them as faint red dots, but they are actually outshining entire galaxies, mostly in the form of hard X-rays. And then there's the cosmic microwave background, sitting out there at z~1300. That was once a sea of energetic photons, just slightly too cool to ionize all the hydrogen in the universe; now it is a 2.7 degree Kelvin hiss in your radio.
Executive summary: you'd better believe you can see cosmological redshifts.
Oh, and PS -- don't ever call it a "doppler shift", that really pisses off cosmologists (or at least the ones in my department). Doppler shifts are the result of objects moving toward/away from you emitting photons that are a different wavelength in your rest frame. In the case of cosmological redshifts, the objects in question are not only not moving away from us, but general relativity doesn't even have a concept of "relative velocities" on these scales. Instead, the photons are actually arriving with a different wavelength, because space expanded underneath them en route.
If you aren't sure there is a difference, try this thought experiment: an observer and an emitter are at relative rest in a static universe, when a photon is emitted. While the photon is in transit, the observer and emitter move farther apart, then come to rest again. The observer sees the photon at its original wavelength, since the motion occurred totally independantly of the photon. Now imagine that, while the photon was en route, the universe expands for a little while. The observer and emitter are in the same end state (i.e. farther apart and at relative rest), but the photon arrives with a reduced wavelength, because this time space expanded underneath the photon.
Quantum mechanics: the dreams that stuff is made of.
No, they don't move faster than the speed of light. The light from those stars moves at the speed of light, naturally. But when the star is billions of light years away, it takes billions of years for that light to reach us. Hence, the light we see from these distant objects is light that is only now reaching us after billions of years traveling through space. We can't see what they look like in the present, only the past.
You had me at "dicks fuck assholes".
Another explaination might be that the stars are young and therefore cool, but I couldn't say that for sure either.
It turns out that there are certain spectral features (element emission/absorption lines) that occur at the same frequency no matter what temperature the object producing them is at. If this pattern of lines is shifted, you know that the colour is due to a real redshift and not a temperature difference.
I suppose that if something like Planck's constant was different at the time and location of the stars, that would also produce an emission line shift, but it's far more likely that the light has just been redshifted.