As Hubble Breaks a Distance Record, We Learn Its True Limits 53
StartsWithABang writes: You might think that, when it comes to finding the most distant objects in the Universe, all we need is a good telescope, to leave the shutter open, and wait. As we accumulate more and more photons, we're bound to find the most distant, faint objects out there. Sure, Hubble just broke its own cosmic distance record, but it's certainly not the most distant. Thinking so misses an important fact: the Universe is expanding! And with that expansion, the wavelength of the light we can see gets redshifted. Ultraviolet light winds up in the infrared, infrared light winds up in the microwave, and the most distant galaxies that are out there are invisible, even to Hubble. Here are Hubble's limits, and how the James Webb Space Telescope will overcome them.
Enticing RSS (Score:2, Funny)
As often happens, my RSS feed display chopped off the end of the headline, and my overactive imagination supplied a much more interesting conclusion:
As Hubble Breaks a Distance Record, We Learn Its True ...
Purpose.
It's a radio... for talking to God!
Re:Enticing RSS (Score:5, Funny)
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Purpose.
It's a radio... for talking to God!
What does God need with a radio?!
Re: Enticing RSS (Score:2)
He doesn't, of course. But the people who gather together and try to talk to him prefer to do it indoors, with the lights on, heat or A/C as appropriate, and sometimes they even pay people to lead these sessions, so they don't have to work at McDonald's to maintain their lives and be somewhat distracted. All that takes money.
It's really very simple. Just think it through.
Re: (Score:2)
Purpose.
It's a radio... for talking to God!
What does God need with a radio?!
Or money, from weekly tithes, for that matter...
Re: (Score:2)
Because putting fist sized gold nuggets in the flower gardens of the churches hasn't worked out so well.
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hush you, plundering church gardens for those has been working out GREAT for me. what the churchgoers don't know, won't hurt them
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Purpose.
It's a radio... for talking to God!
What does God need with a radio?!
see Ancient Aliens theory...
Re: (Score:2)
Because to anyone looking in the other end, they'll seem tiny and far away.
Exclamation marks (Score:1)
Any science article that insists on shouting at me... sucks. I HATE HATE HATE this writer.
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Because using capitals to indicate an exclaimation rather than an exclaimation point makes you look more intelligent?
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Please quit shooting all caps are worse than of what you are complaining, unless they have four in a row in which case fuck that guy there is never an excuse for four exclamation points
(briefly skims blogpost)
nope only one used at a time
Stop with the autoplaying videos, Slashdot! (Score:1)
What were you thinking, putting an autoplaying video on the front page????
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What were you thinking, putting an autoplaying video on the front page????
(Sorry for going offtopic) ... or something.
Strange that video's never autoplay on my computer. Maybe you should install adblock+, ghostery, muter,
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What were you thinking, putting an autoplaying video on the front page????
(Sorry for going offtopic) Strange that video's never autoplay on my computer. Maybe you should install adblock+, ghostery, muter, ... or something.
Yes, because everyone reads slashdot on their infinitely customisable home computer, and not at work.
Emphasize the security aspect (Score:2, Insightful)
Then maybe you should promote these extensions to work's IT department as security tools, citing the use of Flash ads as drive-by Trojan droppers.
Logical (Score:1)
No offense to the awesomeness that is Hubble, but isn't it logical for it to break distance records on a regular basis as more "old" light reaches it simply as a function of time?
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the distance to the visible horizon - the most distant object we can see - isn't growing, it's *shrinking*.
Not yet.
We have a much more firm limit in the form of the image of the Big Bang and it's still within the Hubble Sphere. We technically *could* see past it, but even if we had the hardware, it's pretty much opaque.
Yes, as the universe ages, the image moves away from us at c + expansion rate, and eventually it will vanish behind the cosmic event horizon forever, and since then its acceleration will begi
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Re:Logical (Score:5, Informative)
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What's absorbing in the x-ray region? Certainly not hydrogen, taking a 1s to free would not absorb that much energy.
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That's only if our telescopes could reach the Hubble Sphere. That way light speed + space expansion would be our distance limit and only time would allow us to see objects between the Hubble Sphere and the Cosmic Space Horizon.
But so far with our best equipment we are barely reaching a third of this distance and our limits are still of technological nature - or more accurately of economical nature (we *know* how to build better telescopes that would reach farther, but we don't have the budget).
The scale is backwards (Score:2)
Note TFA has a redshift(z) scale that is backwards. They have z=1 at 6 billion years, and z>20 at 200 million years.
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I puzzled over that for a moment, too. What the time scale shows is age of the universe, or (as the scale is labeled) years since the Big Bang. So z>20 = universe at 200 million years old, not years ago. It's confounding and, to my eyes, counterintuitive, but perhaps that's how cosmologists work.
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I've heard it joked that this is the difference between astronomers and physicists. Astronomers put the observer at the 0-point of the coordinate system, hence larger redshifts are further away. On the other hand, physicists put the 0-point at the "beginning" of the universe: the initial conditions, and mark time after that.
an important fact! (Score:2, Insightful)
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"an important fact: the Universe is expanding!" : Actually, this is not known, only theorized. It's based on the notion that red-shift / blue-shift relate to distance. But that's never been proven, and there are others out there that think it isn't about motion at all. Although we have a consensus opinion that uses it as fact, it isn't a proven fact.
Why is the parent modded down when the post is correct and politely stated?
In my opinion, this is one of the biggest secrets (hidden in plain sight) present in astronomy today. It's highly relevant to every article about space outside our galaxy yet I have never seen an unbiased article in layman's terms discussing the implications of the ubiquitus redshift-distance relation being wrong.
Maybe we have too many professional astronomers with mod points?
Re:an important fact! (Score:4, Informative)
Why is the parent modded down when the post is correct and politely stated?
The GP, at this time, is not modded down. The GP has a history of down modded posts causing bad karma and a low score on new posts.
And looking at the GP's history, this seems to be one of the few times where the post mentions red shift in open-endedly, instead of proposing the idea that red shift is caused by different star ages, something that runs completely against basic physics of how red shift works in both observation and the lab.
It's highly relevant to every article about space outside our galaxy
Red shift is not the only distance measure outside of our galaxy. Stories, even on Slashdot, have discussed subtle changes to those other distance measurements and the impact it has on Hubble's law. And while it is relevant to every article, shouldn't be expected to be in every such article, just as not every article that mentions Newtonian mechanics isn't going to discuss the limitations of using an approximation to relativity.
Maybe we have too many professional astronomers with mod points?
Considering how often the first people to post something using large words around here get modded up, even if failing at intro level astronomy stuff, or how people get modded up for dismissing astronomy theories with no actual basis or content in their post, I don't think it is astronomers with mod points we have to worry about.
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. But that's never been proven, and there are others out there that think it isn't about motion at all
The only two known ways to produce a consistent, wavelength independent red shift are through motion and general relativity effects, both of which are part of the currently accepted theory of the red shift vs. distance relationship.
Or we could have areas of space with greater for lack of a better term "density of volume" where a given space is bigger on the inside than it would appear from out.
http://arxiv.org/abs/1308.6731 [arxiv.org]
(yes the scientist who purposed it called tardis space)
CSI to the rescue (Score:1)
Maybe they should ask CSI for some help. Those guys have tech that can magnify any image to infinity.
StartsWithABang gets an editor? (Score:2)
Wow. Instead of StartsWithABang's usual EndsEveryOtherSentenceWithABang, it's down to EndsEveryThirdParagraphWithABang. Progress!