Most Distant Object in Universe Discovered 229
The_Jazzman writes, "Using the 200-inch Hale Telescope at Mt. Palomar Observatory in California and the 157-inch Mayall Telescope at Kitt Peak, Ariz., astronomers, it seems, have disocvered the ">most distant object in the known universe: a quasar in the constellation of Cetus the Whale." The beastie is about 13 million light years away, making it quite old as well, of course. Update that's 13 billion. Stupid typo :)
Re:13 billion - yay! (Score:1)
Where in the heck did you get this idea? As someone who has done a little extragalactic astronomy, I can say that nobody has ever, claimed that they could close the book on the age of the universe problem. In fact, most astronomers, if pressed, will say that the age of the universe is somewhere between 10 and 20 billion years, but none will give a definitive answer, but may point you at a lot of research that will claim ages from as little 6 or 7 billion to as high as 20!
By the way, the figure of 13 billion lightyears has absolutely no bearing on the age of the universe either. The 13 billion comes about by calibrating the redshift against H0, which is a number that still has a great deal of uncertainty in it. A better value of H0 will pin down the age of the universe, not the observation of high redshift quasars.
Re:13 billion - yay! (Score:1)
Well, newer, more recently derived values of the Hubble variable are better! Aren't they? :)
I know what you mean. I think it's part of the side effect of scientists being human, and wanting their own latest wiz-bang efforts to be better than all the previous ones to date, whether they really are or not.
As for press releases, I know couple of "editors" that I would love to string up in various painful ways for what they've done to some of my press releases. :)
redshift != distance, necessarily (Score:1)
HUH?
How about this?
How about a universe so huge that its collective mass at a distance produces a black SPHERE that makes everything near one seem to be sucked away into a void? Mathematics don't disargue a model like this.
Run the numbers. Try it.
More sane than entropy is, without a doubt.
Re:infinite or just too big to understand ? (Score:1)
He lands squarely in all 3 categories at the same time. The lecture I mention above is a good example of this.
You see some scientists after spending a lifetime examining the universe arrive at the conclusion that something is missing and scientists are hammering square pegs into round holes. Mathematicians are especially prone to this because when they apply probability to "The Big Bang" and it's sister theory "Evolution" they get the same odds I got.
Too close to impossible to have happened this way. That leaves the door wide open for Theology. No other theory actually matches all the observable evidence.
This "most distant object" for instance opens to question the idea that the universe is 12 to 15 Billion years old. After all, the Light from this thing spent 13 Billion years traveling towards us. If we are traveling in opposite directions at less than the speed of light the existence of something anywhere near to that far away in the opposite direction would imply that we are at the center of the universe.
On the other hand maybe scientists have missed the estimates of the cosmos' size and age by an order of magnitude.
Finally the notion of Theologians and Philosophers not observing the universe is in itself preposterous. They do. Sometimes it's by direct observation (Telescope time etc..) Other times it's by reviewing the reports of scientists.
Finally on the matter of "Dogmatic Books". It is worth noting that most theories exist for years before anyone figures out how to test it and then another long wait until the technology exists. See the "WIMP" story for an example. Those areas of the Bible which have been tested have held up.
I.e. There is a single layer of silt well above the layers that hold dinosaur bones that occurs across the entire surface of the planet. It's the only bit of sediment that dose. Geologists say it means we had one big ocean for a very short while. This matches up with Flood. Arguably the most far fetched story in there.
Re:infinite or just too big to understand ? (Score:1)
well they have and the argument has been split every way you care to name. I.e. just because you are in one grope doesn't decide what your opinion on this is.
Dogmatic. Closed mind. Uninterested in other points of view. It looks like being an Atheist and believing in Evolution is a religion for some people.
Neither can astronomers or dentists. All we can do is pile up evidence and try to make sense of it.
This is one theory. Another is that the background radiation has a current source. We won't even have a proper clue until we can check if it exists in space two galaxies over and find the same pattern.
This is some of the reasoning that makes this so fascinating. What if the universe is simpler than everyone likes to think ? I.e. a massive 3 dimensional cloud of stuff. This stuff includes all we can see and a billion times more that we can't. It isn't however infinite. Just too big for us to see the edge. It dose have an age but a lot farther in the past than visible objects suggest. It may be so broad that the light from some objects just hasn't gotten hear yet.
The theories may all be wrong. The measurements may not show what we think they do. Remember when all the Scientists thought the earth was flat and the center of the universe ?
Re:Greatest Living Mathematician?!?! (Score:1)
He made up "Supper K" partly because the audience wasn't all Mathematicians. I am not and yet I could follow the calculations anyway. Also it was his creation and had made it into the Guinness Book as "largest defined number" or something like that.
As for his greatness. Tex is one of the very old pieces of Free Software. There has been a reward out for finding a bug for some years now. The last winner was 1/2 a decade ago.
Re:a pre-FAQ FAQ (Score:1)
The much talked about Cosmic Microwave Background started out as UV, when hydrogen atoms deionized a few thousand (? might be a few million, not sure) years after the Big Bang but has now red-shifted all the way to microwaves
Re:i.e. It's older than the universe... (Score:1)
It is this point that has been contested by recent findings that suggest the expansion of the universe is actually accellerating rather than decellerating. This makes the universe older than it would have been with a decellerating expansion rate. I believe the explanation given for this was 'the pressure exeryted by quantum fluctuations', causing the vacuum of deep space to have a pressure, or something line that.
Re:So the universe is really 14.1 billion years ol (Score:1)
Just a thought.
kabloie
Re:X-Ray observation from ground? (Score:1)
I would agree that the picture is a false color composite, probably infrared through the visible light range.
Re:Something I never understand (Score:1)
But the second part of your question.... hmmm. If this object, that we see now was 13 billion light years away when it emitted the light we see now. Then.... umm.. the Universe was at least 13 billion light years across and is at least 13 billion years old. But I see a (your) problem... if everything started out much closer together then it must have taken quite a bit more time than 13 billion years for an object that is now 13 billion light years away to get there. Ummm... I'm sleepy. Good morning.
13 billion years... (Score:1)
Ok, so if the universe has been expanding for 16 billion years, and this star is 13 billion light years away, that means we're seeing it 13 billion years previously -- which means it must have travelled to the point it was at when we're seeing it in 3 billion years, ie 4 times the speed of light...
?
Re:Ground based to boot (Score:1)
tim
Re:Interesting Link on the story page. (Score:1)
The HST Key Project you're refering to was a project to determine the Hubble constant, H_0. Lots of people have measured H_0 and get a variety of values. The Key Project people got theirs. If you combine a value of H_0 with other cosmological parameters that you think are correct, you can get an "age of the universe". That's what Slashdot and the NY Times like to report, but it's not the fundamental quantity that was measured.
Now, you've got Dan picking out quasars on the 200-inch and he gets a spectrum at Keck. The photons don't land on the detector and announce, "Hey! I've been flying for 14 billion years! It's nice to finally excite an electron!" No, you get a spectrum that tells you the redshift. Dan converts the redshift into a distance using his favorite value of H_0, which might not be the same as the Key Project's.
You used to hear about problems because stellar astronomers would believe that the ages from globular clusters (based on stellar physics) were older than the age of the universe (from measurements of cosmological parameters). That's not what's happening here. Here, you just have people favoring different values of H_0, because they think one value was obtained more reliably than the other.
Re:Ground based to boot (Score:1)
No. There is a testbed optical interferometer at Palomar, but it's used for things like binary stars. It's an engineering test for the Keck interferometer.
You want interferometers and space telescopes to look at small detail, better than the 0.5 to 1 arcsecond you get through the atmosphere. But that doesn't matter here! You still get basically all of the light from the quasar on your mirror (as the atmosphere is pretty transparent), and it doesn't matter if it's smeared out a little. There's no detail to see, anyway.
Agreed, but note that the spectrographic followup was at Keck. That's a common mode of operation these days: If you can image it on the 200, you can get a low-resolution spectrum at Keck.
I think that previously, the most distant objects were quasars found by the Sloan Digital Sky Survey folks.
Re:a pre-FAQ FAQ (Score:1)
Must be a different Palomar than I use, then. The one I know is on the ground, and is an optical telescope. The mirror is polished to optical tolerances, and operates at normal incidence instead of grazing incidence. The atmosphere there is not magically transparent to X-rays, and in fact it's probably not transparent to much at all today, since it's raining.
If it's at z=5.5, then 1500 A in the observer frame is 230 A in the rest frame, which should give you quite a nasty sunburn.
Re:What was that URL again, Bob? (Score:1)
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Re:Something I never understand (Score:1)
It describes real increase in distance faster than the speed of light, not apparent speed. What is important is that this is not travel: two stars can move apart faster than light, but you cannot move from one star to another faster than light. (But as the document I referred to describes, "faster than light" is a tricky term; you can move from across universe in 13 years [in your own frame of reference, not that of an observer])
The paragraph about the moon revolving around your head is the next one in the document; the URL I posted had an anchor but perhaps your browser didn't show you the correct part of the document.
Re:Something I never understand (Score:1)
That accounts for part of this paradox.
See: http://math.ucr.edu/home/baez/physics/FTL.html#13
Re:So the universe is really 14.1 billion years ol (Score:1)
Re:Furthest away? (Score:1)
Wow - that thing really IS old - it even still has an original compuserve address.
Wrong: super-inflation (Score:1)
including one called super-inflation,
to reconcile certain kinks in the distribution
of matter and energy.
However, in a pragmatic sense, the knowable part
of the universe is limited to lightsphere the
age of universe.
Re:Greatest Living Mathematician?!?! (Score:1)
I believe that would have been Bjarne Stroustrup [fatbrain.com].
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grappler
Re:while we're being nitpicky... (OT) (Score:1)
<P>
<I>apenootjes</I>
Re:while we're being nitpicky... (OT) (Score:1)
Re:while we're being nitpicky... (Score:1)
Sometime in the past someone in the States did not do his math right.
Historically a 1000 million is called a milliard.
This is still so in "the rest of the world" but about 20? years ago the UK decided to adopt the US "slang" of billion, yet educated Brits do see the potential for error and now prefer "1000 million".
The international way:
million : 1000,000
milliard : 1000,000,000
billion : 1000,000,000,000
billiard : 1000,000,000,000,000
trillion : etc,
trilliard : etc,etc.
Hmmm, why do my HTML tags not work?
Re:Slashdot should show some forward thinking... (Score:1)
An Inch is <B>exactely</B> 2.54 cm,
That's how the US and British governement institutions have "standardised" this obsolete system.
For accuracy I prefer to use the system in wich something is designed.
Re:Something I never understand (Score:1)
Re:Something I never understand (Score:1)
An earlier post helped explain with a balloon example, and I know that such an example is often used to try to demonstrate the "inflation" of the universe; and perhaps that explains this all. It just is a bit tricky for me to grasp. I get confused when astronomers talk about such distant objects as being "young", and that the farther away we see, the closer to the big bang we are looking (ie. perhaps just a couple billion years after it happened). The "inflation" is supposed to explain how things can get to be 13 billion light years away, while only being a couple billion years old. If something is 13 billion light years distant, why is the universe not at LEAST 26 billion years old (since if it were receeding at the speed of light, that is the minimum round trip time.)
Drawing black dots on a balloon shows how, as the balloon inflates, the dots move farther apart, and yet the dots themselves aren't moving across the surface of the balloon. Okay fine... Does that mean what we see as receeding matter is still an artifact of an expanding space, while in reality, we are not really moving (much) on the surface of our balloon (ie. space-time)? Is our local movement, due mainly to the coalescing effects gravity, just a minor perturbation of a continually expanding space? Rather than thinking of everything being blasted apart from a single point, is everything really just staying more or less in the same place, but shrinking at such a fast rate that the density of space it continually decreasing, and distorting our scale to make it appear that everything is actually moving away from us?
Ummm, sorry for so many questions...
what is going on? (Score:1)
[ c h a d o k e r e ] [dhs.org]
Re:Greatest Living Mathematician?!?! (Score:1)
Re:Something I never understand (Score:1)
Re:So the universe is really 14.1 billion years ol (Score:1)
knowns (Score:1)
So, what about the unknown universe? well, we don't know about it because it's unknown!
Re:question (Score:1)
Asking what is outside the universe is like asking what is to the north of the north pole. Universe is defined as being "everything" just like the north pole is defined as being "here in this spot".
Q: Age (Score:1)
So does this point us in the direction of the center of the universe?
Q: Search for things (Score:1)
Re:Q: Age (Score:1)
now in terms of why vaccuum has a finite, non-negative energy density...thats an interesting question!
Re:question (Score:1)
my Dept Chairperson (he is an experimentalist) was expressing distain for an intermediate expression in a derivation I was doing, saying, "thats like asking which direction is north when you're standing on the north pole".
I replied, "exactly".
He said, "so its meaningless, standing on the north pole there is no direction north".
I said, "Of course there is! The north pole is an abstraction, a singularity. Standing on the north pole most of your body will be surrounding the point in question. One must then go at right angles to our space-time into the singularity. This way is north"...I pointed to my chest..."when standing on the north pole".
Re:Question to all: Do you think it is _still_ the (Score:1)
So the universe is really 14.1 billion years old? (Score:1)
Re:Q: Age (Score:1)
Imagine a balloon, or a globe if you prefer. Never mind expansion at all. Consider the surface only, not the interior. Now, where is the center of the surface? There isn't one in two-dimensions. The center of the globe is inside of it, not on the surface at all. Now just add a dimension, and you understand (kinda) why we can't say where the center of the universe is in three dimensional space.
Re:"The Most Distant" is Misleading (Score:1)
Good point. Hadn't thought of it from that angle. Of course, no one can say where the unknown universe is hiding.
dTinkrer
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Have you ever seen a gruntled employee?!
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Re:Something I never understand (Score:1)
This assumes that the object is moving at light speed. I am not sure how fast it is moving, but I am fairly certain it is not moving away from us at the velocity of light.
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Re:Something I never understand (Score:1)
What the article at the URL you posted [ucr.edu] describes is apparent motion as measured by an observer from a third frame of reference. See the paragraph with the heading of "The moon revolves round my head faster than light!"
We are measuring the distance between us and a very distant quasar so the case of special relativity you mention actually does not apply.
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Re:Something I never understand (Score:1)
That's a thought provoking question. Perhaps the calculation takes into account the distance the object has traveled since it emitted the energy. If so, the quasar is currently 13 billion light years distant.
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Re:"The Most Distant" is Misleading (Score:1)
The "known" universe is also a vague term.
Calculating that the light from an object has traveled for 13 billion years does not mean that we now "know" the universe within that span of 13 billion light years. We just know that, based on our current model of cosmology, the universe apparently has a span of at least 13 billion light years in that direction.
See what I mean?
It is more accurate to report that it is "the most distant object yet discovered".
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"The Most Distant" is Misleading (Score:1)
It is a remarkable find, though.
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Re:Will we ever see the big bang? (Score:1)
Uhm, that requires infinite engery. Now unless you can pack a nuclear station in your pocket, we won't be colonizing the universe anytime soon.
Cheers
Re:Ground based to boot (Score:1)
You do realize that trying to "cover" all the directions away from the earth is darn near infinite.
Analogy: Pretend you wanted to build a spehere around the earth, but you only had one type of object: a interconnecting square tile with dimensions of only 1 meter by 1 meter (or foot for the Imperialists
Hope that made sense.
Cheers
Re:Will we ever see the big bang? (Score:2)
Well, speaking as a layman, yes.
One of the predictions that is made by the Big Bang theory is that there should be background radiation in the microwave segment of the electromagnetic spectrum all around us in space. And as it turns out, that prediction is correct. There is a cosmic microwave background radiation that is observed. Now you might be wondering what this has to do with the Big Bang. That's a good question, and as a layman, I can only answer it to the best of my ability. So here goes.
When we look at distant galaxies, we know that they are rapidly receding from our own galaxy. How do we know this? It's the redshift. Think about it; light is being emitted from objects in the form of waves. If an object is moving swiftly away from you, then when that object emits the next "wave crest" of light, it is further away, therefore the wavelength is longer. When you look at the emission lines of distant galaxies, you find that the light is "shifted to the red"; it is shifted because the galaxies are receding so quickly that the light has been shifted towards the "red end" of the electromagnetic spectrum.
Now the same thing applies to the Big Bang, only on greater scales. If we are talking about the event that began the universe, then it would be (by definition) at the beginning of time. Now, the same processes that shift the light of a galaxy into the red would presumably be working for the "light" of a "big bang." In fact, the "light" would be so far red-shifted that it would be outside of the visible spectra and redshifted well into the microwave. Why? Because it is "so far away", in terms of both distance and time.
And that is what we see. We see a cosmic microwave background radiation pretty much uniformly in every direction in space. And that is what the CMBR is
Re:question (Score:2)
I'd suggest you read Mikio Kaku's book _Hyperspace" for an introduction to the concept of higher dimensions and how they work into modern physics.
That depends... (Score:2)
If, as some have suggested, it's the shell around a Black Hole, then the shell is unlikely to have survived to the present day. The density of matter in the Universe is far too low to sustain such a beast.
Could a Black Hole have survived to the present day? Hmmm. Black Holes evaporate, with time, which is a big relief to the rest of the Universe. (If they didn't, I'm not sure there'd be much of a Universe left.) However, whether it's survived depends on how large it got and at what point the mass intake was exceeded by the mass evaporation.
There =is= an interesting possibility, here. Galaxies have formed around Black Holes - this much is now reasonably certain. Galaxies could therefore be the remnants of Quasars. You have a super-massive Black Hole, already made for you, and it =would= explain why there aren't any nearby Quasars at all. They are ALL extremely distant (and therefore extremely old), prior to, and only a short while after galaxies start appearing.
infinite or just too big to understand ? (Score:2)
For years scientists, Philosophers and Theologians have been arguing over weather the Universe is infinite in size an age or if it's just very big and old.
What dose the greatest living mathematician and possibly best programer have to say on the subject ? Well he starts by cooking up an equation that will generate a number so big as to not make sense to us. With so many digits that it would fill volumes if printed out. He calls it "Supper K".
Then he goes on to say "I would give up immortality to live for "supper K" years. After all how would I know the difference ?
So what's the point ? My guess is that each time the engineers build a better telescope the Astronomers will find a farther and older item. Eventually they may get to something that's past the alleged age of the universe and start to revise the Big Bang theory.
This won't necessarily mean the universe is infinite however. Just that we can't see the end of it. The next question of course; Is there a difference ?
URL for Knuth Lecture (Score:2)
http://www.technetcast.com/tnc_program.html?progra m_id=50
Re:i.e. It's older than the universe... (Score:2)
Furthest away? (Score:2)
Too bad Zaphoid really /is/ the center of the universe....
Re:while we're being nitpicky... (Score:2)
A wormhole? Shortest path, perhaps....but Wormholes do not change the distance from one object to the next. They just get you there a hell of a lot faster by bending and shifting spacetime. (Physicists have been trying for a long time to mathematically construct wormholes that won't collapse on on themselves, fly apart, or break other laws of physics....but it hasn't been done yet.)
Also, wormholes are theoretical. So until they're proven, 13 billion light years it is.
-- Give him Head? Be a Beacon?
Speaking of Bacon - (Score:2)
I think the only differance between Theologians and Scientists is they both try to understand the big picture, they both get inspired flashes of 'insight' and understanding, but the Theologian claims it was a telegram from God (and some realizations can be VERY powerful and life changing, as if it were) and writes it down in the one true book of facts, while the scientists isn't quite so trusting and faithful and devises experiments to test the validity of this 'hypothesis' - or you could say that ancient religious texts are 'great ideas' that have survived the test of time.
Anyway, when Copernicus or Kepler or whoever it was pouring over the record of observations and *finally* saw the simple pattern of elipses and realized what was *really* going on, I'll bet it was a powerful experience, it matches the data - whereas other people may get powerful inspirations that just leads them to do crazy things. Sometimes just to survive you HAVE to do crazy things!
The edge of everything (Score:2)
adamp
Not that surprising, actually. (Score:2)
Re:Q: Age (Score:2)
I'm no expert, but I don't think the expansion of the universe is accelerating. Rather, it may not be decelerating fast enough for gravity to ever pull it all back in (ie. it may expand forever, since gravity gets weaker between more distant objects), which is what is called an "open" universe. "Closed" is if gravity eventually will be able to reverse it all. Either way, the rate of expansion should be slowing due to gravity...
But maybe someone else will correct me. :)
Something I never understand (Score:2)
Alternately, if the light *started* towards us 13 billion years ago, and the emitter is almost as old as the universe, then isn't that object now about 26 billion light years away? And if so, how can the universe only be 15 billion years old?
But Big Bang is Further still (Score:2)
Re:Q: Age (Score:2)
Re:The edge of everything (Score:2)
Re:So the universe is really 14.1 billion years ol (Score:2)
Re:infinite or just too big to understand ? (Score:2)
Re:infinite or just too big to understand ? (Score:2)
Re:infinite or just too big to understand ? (Score:2)
Re:infinite or just too big to understand ? (Score:2)
Re:Slashdot Accuracy? (OT) (Score:2)
I'm not criticizing the model, I'm criticizing it's implementation. I think it's good that Slashdot is quick, but honestly: how much longer would it take if they checked for grammar and spelling errors? Maybe 5 minutes; BFD. And if they did a little research on the actual subject they were posting, to make sure it wasn't being misrepresented? Maybe 30 minutes?
Well, as it is, I know they are swamped with submissions, so an extra 35 minutes per story would actually add up real quick. But guess what? They're part of VA Linux! They can afford to hire a staff of editors! There's just no excuse anymore.
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"You can't shake the Devil's hand and say you're only kidding."
Re:Slashdot Accuracy? (OT) (Score:2)
What they need to do is have a staff of editors. It's not like they can't afford it. C'mon Malda - get on the ball here.
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"You can't shake the Devil's hand and say you're only kidding."
Since when... (Score:2)
Chris Hagar
Re:Question to all: Do you think it is _still_ the (Score:2)
The reason why this is relevant is that matter + antimatter = lots of energy, whereas matter + exotic matter = nothing, thus preserving conservation of energy.
What actually happens is that everywhere in the universe, pairs of particles with positive and negative energy are constantly appearing, as a consequence of quantum mechanics. Normally these particles immediately annihilate eachother, leaving nothing, but near a black hole, the negative half of the pair sometimes falls past the event horizon before it can find its mate. Once it does that, there's nothing that can get it back out again, so the positive particle becomes "real". (And the black hole, having "gained" negative mass, becomes smaller.)
The thing is, larger black holes take longer to evaporate than smaller ones (maybe because of tidal forces?), and for all but the very smallest (hypothetical) black holes, the leftover radiation from the big bang is more than enough to offset the evaporation and keep them growing. So yes, the quasar in question is definitely still around, although I have no idea whether it's still a quasar or not.
(IANA cosmologist. Or a quantum mechanic.)
Re:Q: Age (Score:2)
An epicenter is a point on the surface of the earth to which the distubance of an earthquake can be traced back.
epi- = surface
epicenter = surface-center
It's the point that matters when it comes time to assess damages and make predictions for aftershocks and the like. The actual center of an earthquake could be 500 meters down and two steps to the left
IF somehow the big bang (great sex?) theories hold out, and we are actually on the surface of a 3+1 dimensional (3 space + 1 time) hypersphere, then we still wont be looking for an epicenter of the big bang. We'll be looking for the actual center - which I've heard rumored is actually a time warp away, a jump to the left, and a step to the right.
However, if you wish to postulate an epicenter, I'd be really interested in the hypothesis. Heck, I'll postulate that there is one and it's our sun...oh great, there's a call on line 1 from Mr. Torquemada. Got to run!
Re:Q: Age (Score:2)
So:
Earth : 3d -> surface of earth : 2d -> epicenter : (x_0,y_0)
Universe : 4d -> now : 3d -> epicenter : (x_0,y_0,z_0)
You were right about the epi- part, wrong about calling all of now the center.
BTW: There are 360 degrees (2 PI radians) in a circle and 4 PI steradians in a sphere. I don't know how to describe parts of hyperspheres, but I'll guess it's sterochronoradian, (stero- solid; chrono- time; -radian like radius, meant ray or spoke). There are probably 16 PI of them in a hypersphere, but that's just a guess.
Re:Slashdot Accuracy? (OT) (Score:2)
'No, Mr. Malda, 13 billion cannot be expressed in Gazillions, nor is it only slightly more than you made last year. Now let's discuss that story you posted while I was out for lunch. Wasn't there a better way of describing the new AIBO add-on than 'Your cyberpet can new give the fire hydrant stiff compitetion' from the '40,000-PSI-cant-be-wrong dept.' For crying out loud, if you're going to say something crass, at least use appropriate punctuation and ispell!'
Re:Slashdot should show some forward thinking... (Score:2)
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Re:The Final Word on English VS Metric (Score:2)
A Cup is 0.237 liter. I happily use either 0.2 liter (a glass) or 0.25 liter (a "metric" cup) measurements.
A Pint is 0.473 liter. I'm happy with half-liter beer servings. My wife prefers 0.33 liter -- half-liter (or pint) is too large and quarter-liter (or half-pint aka cup) is too small.
A Gallon is 3.78 liter. (US gallon, that is; British is more like 4.55 liter.) Dunno; I buy milk in one liter quantities as I hate the taste of "long-live" milk.
A Mile is about 1.6 km. Well. Speed limits are usually posted in increments of five. Smaller unit allows for finer granularity.
You see, every coin has two sides.
I happily admit that binary fractions used in Imperial system are much more appealing to hacker/nerd types like me :)
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Re:Stupid question (Score:2)
Imagine a sphere. A balloon. Earth is a spot at the surface of the sphere. (The sphere is actually 4-dimensional, but its easy to visualize the picture in 3D.)
For simplicity we'll say that both quasars are 13 billion LY away, and the universe is 13.1 billion years old.
The first quasar is almost diametrally opposite on to the Earth on the balloon's surface. So is the second. The distance between them is more like 0.2 billion LY.
Or rather they were that close 13 billion years ago, right after the Big Bang -- which is the time their light needs to reach us. Actually, everything was that close. As our balloon inflated, the distances scaled accordingly.
This is of course very simplistic but more or less correct (I think).
IIRC we're prevented from seeing past the diametrally opposite point, because time needed by light to reach us from there is greater than the age of universe. Or something like that.
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Re:Will we ever see the big bang? (Score:2)
Just turn on your television :)
10 percent of that black/white static you see is caused by photons left over from the big bang.
sorry to rain on the quasar parade (Score:2)
"We have identified nearly 3000 faint galaxies, of which nearly 1000 galaxies are of redshift z > 2 and more than 50 galaxies are of redshift z > 5 (ranging up to and beyond z = 10)."
Now, I should caution you that these are photometric redshifts, somewhat more speculative than those derived from matching spectral lines (as was done with the quasar atz=5.5). But in principle with large enough telescopes we can go back and do the spectroscopy and verify these redshifts, they won't all be correct but most of them will.
Another interesting possibility that you should look at if you are interested in having a clever answer to the question 'what's the furtherst thing in the universe' are gamma ray bursts. Though redshifts for these are hard to get it is possible to make speculative arguments about their redshift distribution based on the idea that some of them may appear to 'last longer' due to cosmological time dialation.
Finally, as several others have already pointed out the Cosmic Microwave Background estimated to be at z of about 1500, is about as far away as we are going be able to see. Farther off, you are looking back into the universe when it was so hot and dense that it was 'opaque'. The CMB represents the point in the evolution of the universe when things cooled enough for neutral atoms to form. It turns out that electrons running around without a proton make it really hard for photons to get anywhere in a straight line. At z=1500 those free electrons got used up to make neutral hydrogen and the universe suddenly became 'transparent'.
Incidentally, the universe had to become transparent for the gas to ever cool and form galaxies, stars, planets, and people. In this way and many others the cosmic microwave background represents the beginning of all of the structure that we see around us.
Ground based to boot (Score:2)
I'm assuming they used interferometry, though the article didn't say so?
And it was Mt. Palomar and Kitt Peak to boot. I've been expecting this stuff to come from Hawaii. Kudos to the scopes on the continental US!
I guess this officially beats the Hubble Deep Field which WERE the most distant objects found in the universe.
Re:a pre-FAQ FAQ (Score:2)
This is completely wrong. yes, it is "red" in that its very redshifted towards the radio part of the spectrum. since its moving away from the earth, its light wavelength gets "stretched out" and redder depending on how fast its moving. Far away galaxies are moving away from the earth faster, so they are "redder" . If they were moving towards us their light would be shifted in the opposite direction and would be "bluer" since x-rays are way towards the "blue" end of the spectrum, this galaxy cannot be emitting light in the blue end of the spectrum, unless it were moving towards us at a fantastic rate, which in and of itself would be an important discovery. Secondly, since this galaxy was found using earth based telescopes, theres no way in hell it could be in the x-ray part of the spectrum, because the atmosphere acts like about 3 feet of lead to any x-rays trying to get through it. And all you have to wear as an x-ray technician is a quarter inch, you do the math. thats my two bits
Re:Will we ever see the big bang? (Score:2)
You can be a little more precise than just saying it's a relic of the Big Bang, though. The CMB is basically the remnant afterglow of the moment when the Universe became transparent to its own radiation -- before that, for various reasons, photons couldn't get very far. There's a lot more going on here than I really want to go into, but a couple important points: the CMB is a very important reason why we like the Big Bang theory. It has the spectrum of a perfect blackbody (to within one part in 10^5 or so) at 3 K (and yes, that apparent temp. is a result of the redshift); that fact alone imposes pretty fundamental limitations on what could've happened in the early stages of the Universe. (It turns out, for instance, that you can't have had energy injection by spooky other particles, because we would see a non-Planckian CMB.) Furthermore, one particular property of the CMB -- that it looks the same wherever we look (once you have accounted for the motion of our galaxy relative to it) -- is one reason we like inflation, which suggests that one very tiny region of the initial Universe underwent a period of unimaginably speedy expansion. (Again, this can get arbitrarily complicated. But the point is that in a simple uniform expansion, the stuff to our left and the stuff to our right would never have had the chance to equilibrate with each other; hence, they should look different. Inflation "solves" this by requiring that everything we see came from one very very tiny region in the initial Universe.)
Re:sorry to rain on the quasar parade (Score:2)
As you mention, the "most distant" things that have been observed (to my knowledge) are so-called "blue drop-out" galaxies. (You're probably aware of this, but: You take an image in several wavelength bands, and find some galaxy that is definitely present in the longer-wavelength ones but gone in the short-wavelength images. By figuring out the point where the galaxy disappears, you can in principle determine its redshift. Less precise -- and also much less time-consuming -- than spectroscopic redshifts, for obvious reasons. :-))
13 billion - yay! (Score:2)
The problem? It came out to be 8 billion years.
So a bunch of extra-galactic types dusted off their hands and said "well, that's done" and completely ignored that for years stellar evolution models had the lifetime of stars like the Sun to be on the order of 10 billion years, with lower-mass stars having older life times. There are lots of halo stars whizzing by near the Sun that are definitely older than 10 billion years, and the CMD's for globular clusters place their ages over 10 billion years.
I just like seeing things overturned. :-)
Re:"The Most Distant" is Misleading (Score:2)
That *would* make it the most distant object in "the known universe", or more accurately, "the observed universe". The "known universe" now has a maximum extent of 13 billion light years.
If you can't figure out how to mail me, don't.
Scientists, save your time... (Score:2)
Duh.
13 billion (Score:2)
Re:Slashdot Accuracy? (OT) (Score:2)
And slashdot is very quick, even when posting old stories. I guess if you want accuracy in your stories, you must go to some (very few) specialized usenet groups. Is there some sci.astrophysics group?
Unfortunately, to be able to participate in some of the sci groups you need to be an expert. I really miss those Isaac Asimov's essays in the Fantasy and Science Fiction magazine, where he explained things in clear language for interested laypeople.
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Re:Will we ever see the big bang? (Score:2)
Question to all: Do you think it is _still_ there? (Score:3)
Thirtenn Billion Years is a Very Long Time [tm], even for a quasar, it is _still_ a very long time.
So, do you think that quasar is _still_ there? It it is not a quasar now, what will it be? A white dwarf? A blackhole? What?!
Re:Will we ever see the big bang? (Score:3)
The microwaves are (part of) the initial energy, they've been streched as the universe has expanded. It's like drawing a wavy line on a balloon and inflating. The wavelength increases as the surface gets larger because (somehow) it's 'connected' to that surface. (wavelength increase = frequency decrease = redshift)
Light from receding emitters is redshifted in the same manner as a sonic doppler shift. (A train whistle lowers in pitch once it passes you.) This is easier to show with pictures and I think it's probably understood, so I'm leave it at that.
There are still other sources of redshifts. As light is emmitted from a massive body, it loses energy to escape gravity. A loss of energy is the same as (or causes?) a redshift. (Energy per photon is greater at greater frequency.)
There are still other sources of redshift, but I don't remember all of them. Technically, these examples can be seen as manifestations of the same thing, but that's for some other time.
ATCT = According To Current Theory
NPI = No Pun Intended
Re:Something I never understand (Score:3)
Expansion Rate of the Universe. (Score:4)
Type Ia Supernovae are known to have a specific luminosity peak. From this you can determine its distance. From its spectral redshift, they determine its recessional velocity. Using this information, they determine that the Universe is between 12.5 and 15.6 Billion years old. It puts H0 at 64km/sec/mpc.
The Supernova used for this paper was SN1998bu.
typo alert! (Score:4)
Slashdot Accuracy? (OT) (Score:5)
OK, I just have to say this - and I have the karma to burn, so...
Why can't you guys do even some basic proofreading of your stories? So far, out of the past, maybe, 20 stories, probably 18 of them have had SOME kind of error in them. I'm not expecting perfection, but Rob, you said yourself in "Geeks in Space" that you are now a journalist. Journalists check their facts and journalists proofread.
I mean, come on. You can make a few mistakes here and there, that's fine. I'm not going to go screaming about every single one. But, really.
BTW, Who's jimjag?
If you can't figure out how to mail me, don't.
a pre-FAQ FAQ (Score:5)