'Long Time Ago' and 'Far, Far Away' records broken by new GALAXY With the power of Hubble and Spitzer combined, NASA has spotted the most distant galaxy ever pictured, around just 420 million years after the Big Bang. Most distant galaxy MACS0647-JD A new programme, known as the Cluster Lensing and Supernova Survey with Hubble (CLASH), uses the Hubble and Spitzer space telescopes and the …
If I was a gambling man and thought I would live that long I would happily risk a few quid at the bookies betting that mankind will have a working FTL drive before the end of this century, I suspect I wouldn't get very good odds though.
Still wouldn't bet that in a million years a voyage of 13.3 billion light years would be feasible, although I am not going to down vote you because I admire optimism, however misplaced.
It just assumes that the light emitted by [some object] has travelled for 13.3 billion years through expanding space and was appropriately redshifted. We thus see the given redshift of [some object]. I do think that the relationship between "distance travelled" and "multiplier of the original wavelength" is linear, so does not take into account slowdown (due to self-gravity) or speedup (due to dark energy) effects, but then again, I'm a cat.
"The galaxy is so small, less than 600 light-years wide, that it may be in the first steps of expanding. "
Hang on a sec..... 13 billion years ago, (ie. our observation of it) it was 600 light years wide. Nowadays, it's probably as big as, er, well, possibly pretty big. Or it may have shrunk to something the size of a pin head.
Anyway, I still think that picture is a speck of dust on the lens.
Top marks to the astro-boffins who do this kind of thing. It still fires my imagination just like when I was a child.
"Hang on a sec..... 13 billion years ago, (ie. our observation of it) it was 600 light years wide. Nowadays, it's probably as big as, er, well, possibly pretty big. Or it may have shrunk to something the size of a pin head."
That's kind of the point of it being so interesting...
Even presuming that the universe is spherical (as opposed to a closed-circuit geometry where everywhere goes back on itself), no-one appears quiet sure if the edge of the observable universe IS the edge of the universe or:
the edge of the OBSERVABLE universe (i.e. light vanishes after this point, due to speed etc...).
Of course (just to clarify); if it's the edge of the universe completely, we take it to mean that matter "runs out" at that point. That it is the farthest to which galaxies have expanded period.
Hmm. It's almost certainly one of these three; just to recap:
Non-relevant geometry. Actual physical limit of matter. Light "fall off" point.
Or (d); something we hadn't thought of?
"the edge of the OBSERVABLE universe (i.e. light vanishes after this point, due to speed etc...)."
Actually the light we see in the scopes was originally produced by the big bang and its remnants - so light (as we know it) didn't exist before the big bang.
So based on current science the big bang (or technically a bit after it) is the limit of what we can see by detecting light.
Sure; I'm aware of that, and many other explanations. It is a most reasonable one. Based on that, eventually the observable universe will be greater than when before. Only given the slow (relative) rate of expanse, we are unable to see either things moving beyond this limit, nor anything "dropping out of the field of visibility" (again; obviously if indeed that were possible...).
But; is it not also of some coincidence that the objects at the periphery of the observable universe are travelling at a significant proportion of the speed of light? Many are convinced this is not a coincidence. We do not know of matter at what point in such massive acceleration that light ceases to be "transmitted backwards." Leading many scientists to keep an open mind as to whether this speed is linked to a physical phenomena which is limiting at this point. So; I digress (back to where I started). It would indeed be a bit of coincidence if the universe had "happened" to just expand to this speed, at it's maximum distance from us, just now?
"eventually the observable universe will be greater than when before. Only given the slow (relative) rate of expanse, we are unable to see either things moving beyond this limit, nor anything "dropping out of the field of visibility""
Yeah the universe is expanding at an accelerating rate, that was established a long time ago. But the only way something can "drop out of our field of vision" is if it is travelling faster than the speed of light. Any speed below the speed of light and light would continue to be "transmitted backwards" or towards us to observe.
According to physics nothing can exceed the speed of light without warping space or such. If that assumption is wrong, then agreed we can't be sure where the edge of our universe actually is. But so far all evidence points to that being right.
Of course there could be more universes beyond the edge of ours, where light hasn't made it to our neck of the woods.
The concept of horizon in cosmology is a bit misleading. It is true that nothing can travel at a speed larger than the speed of light, however very distant galaxies are observed having a recession velocity larger than c. This is congruent with general relativity because its the space itself that is expanding. In fact, due to the accelerated expansion, in a distant future we will be able to see only objects in the local supercluster.
https://en.wikipedia.org/wiki/Cosmological_horizon#Particle_horizon
http://arxiv.org/abs/astro-ph/0310808
"Sure; I'm aware of that, and many other explanations."
There are no other explanation, chap: The observable universe IS as far as we can see. That's it's very definition. So of course the observable universe gets larger every time we get a better telescope, or discover particularly far away. And of course the universe is larger than that.
http://en.wikipedia.org/wiki/Observable_universe
The *actual* universe has been estimated at 78 billion LY... but nobody knows for sure.
"But; is it not also of some coincidence that the objects at the periphery of the observable universe are travelling at a significant proportion of the speed of light?"
Not as far as I'm aware. Citation, please?
"Many are convinced this is not a coincidence."
Citation?
"We do not know of matter at what point in such massive acceleration that light ceases to be 'transmitted backwards.'"
Huh? Einstein write a bit about this, didn't he?
Genuinely looking for an explanation and citations here.
Call me stupid, but wouldn't it be possible to travel faster-than-light through the same area through which they are using gravitational lensing? Although doubtless a long, long way away; yet, it can't help you getting but a little bit excited, no? And; if in the affirmative, what factor of c is attainable? Hmm. Perhaps warp speed IS possible, after all...
For a few moments I thought Samsung had released yet another version of the greatest smartphone around today!
Given that this discovery involved the aged Hubble Telescope, we have to grateful that the engineers fixed the wrong formula optics and that NASA has always found enough funds to send the maintenance crew up there.
How many other investments have returned such a bang for the government buck as has Hubble? The US Government deserves a hat tip for this one.
"How many other investments have returned such a bang for the government buck as has Hubble? The US Government deserves a hat tip for this one."
And the Hubble deserves a better fate than burning up in the upper atmosphere, it's one of the few things that really deserves to be returned to the earth upon completion of it's mission, to be displayed for all to see in the Smithsonian.
Sure, there would be a specially designed and build return system that needs to be launched but the cost of recovery would be well worth it for the inspiration and answers Hubble has provided over it's lifetime.
"NASA has spotted the most distant galaxy ever pictured". Got some spare time? Why not try find some more:
I mean seriously...
Perhaps you could take up a hobby of counting all the grains of dust in the world.....
And like.. what then?
These scales are just SOOOOOOOOOOOOO huge.... that is distance, time, velocities, the amount of deadly radiation between here and there....
Travelling to there at the speed of light - that's fine if you can actually GET there, and SURVIVE the trip and somehow can live 14 billion years and a few more, and then transmit the signal back... if it ever gets detected...
Some 30 billion years later.....
I mean it's great that this is being done, but I watched the first 6 videos on the scale of the universe, in the Khan Academy and it just fucked my brain.....
www.khanacademy.org/science/cosmology-and-astronomy
I am not saying that you should not see it, and I am not saying it's bad, but your getting fed great information in a very mentally digestable form - and that is the problem.......
I mean it's GOOD to see, but it's just too much to take in.
This whole "size of the universe" business - there is just too much of it, both what is within the observed universe, and how big the actual size of the observed universe actually is.
Brilliant tho, bit it IS just too fucking much.
>I mean it's great that this is being done, but I watched the first 6 videos on the scale of the universe,
>in the Khan Academy and it just fucked my brain.....
>www.khanacademy.org/science/cosmology-and-astronomy
>I am not saying that you should not see it, and I am not saying it's bad, but your getting fed great
>information in a very mentally digestable form - and that is the problem.......
>I mean it's GOOD to see, but it's just too much to take in.
I've never seen that Khan Academy stuff before. I know things are utterly huge, I know times and distances are too vast to really contemplate properly, but this stuff is very good for giving a numpty like me some sort of understanding of the scales involved.
You're right, it's far too fucking much, but brilliant all the same.
You sit in work thinking "I'll never meet this deadline, the customers will go nuts, my boss will go into meltdown, I'm fucked" and then you look at this and realise how completely and totally irrelevant your own miniscule problem is. Even if my work-related fuckup somehow resulted in the earth flying into the sun, it wouldn't even be a noticable event.
People fighting in the middle east and stuff should be sat down in front of things like this, and then asked at the end "what the fuck are you bothering for?"
"meaning its light has travelled 13.3 billion years to reach Earth" - or in God-speak a little under 6000 years.. If you do the maths and reach the logical conclusion that the speed of light is actually 2.28 million times faster than so-called physicists keep trying to convince us it is, then the universe is of course 6000 years old.
Because a sky fairy gives *control*. It's essentially benign and anthropomorphic in it's whims, which means that the universe is a 'safe' place and someone is looking after it, and there is a meaning to life, you don't just die and that's the end of it ,and 'everything happens for a reason' (so the rich can justify their wealth, and the poor can kid themselves that it's their fate and for the best).
It makes people feel safe.
The idea that it's all just luck and matter, with no 'great plan' and no afterlife is frightening in comparison.
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