Oldest Space Object To Date 33
Wind Walker writes "CNN has an excellent article regarding a recently-discovered galaxy that's more than 14 billion light years away. "So what?", you're probably asking. Well, this galaxy (unnamed at the time) is said to have formed during the cosmic Dark Age (between 500 million and 1 billion years after the Big Bang) when no galaxies should have been giving off light."
Huh (Score:2, Interesting)
Or maybe galaxies just formed faster than we thought.
Re:Huh (Score:2, Insightful)
Re:Huh (Score:2)
Oh wait, that's Scientology. Never mind.
Re:Huh (Score:1)
Re:Huh (Score:1)
The bible's estimation is grossly inaccurate. At least science's 14.5 B year old universe was in the ballpark. But I see you point. However, the scientific method almost always produces results that are either very close or exact. You certainly can't claim that the bible gets scientific stuff anywhere close to right. Like the Flood, creation, etc, etc. It's grossly innacurate.
Re:Huh (Score:1)
The speed at which a galaxy forms has nothing to do with its distance from us. Light travels 299,792,458 m/s (in a vacuum) no matter how fast the galaxy forms.
Re:Huh (Score:1)
Yeah. I know that. You misunderstood me. I was just saying that maybe the universe was still created 15 billion years ago. To account for this very old (14 byo) object found, I was just saying that maybe galaxies formed faster than we thought. Maybe they only took 1B years to form, instead of 3 billion, which could account for this 14 billion year old object.
However, I really think that the universe is just older than we thought. I doubt a galaxy would form in 1 billion years. The universe is probably 17 B Y O.
Re:Huh (Score:1)
Damn... so do I
Somebody sneezed (Score:1)
I'm serious - I wonder how many of these images are accidental defects in the photo plates etc.
Anybody ever head of a news relezse and then retracting it?
Re:Somebody sneezed (Score:1, Troll)
Re:Somebody sneezed (Score:2)
Charge coupled devices (CCDs) like those used in modern video cameras, digital cameras, web cams, etc. are what's used. Usually they're supercooled so as to mitigate emission in the IR region by the detector itself.
So this new galaxy is actually frozen snot. How does this affect the age measurements?
Measuring distance of the stars (Score:5, Informative)
Extracted from http://benps.benallaps.vic.edu.au/Science/Earth/s
How far to the stars?
On a clear dark night, the stars can seem to be very close indeed and they all seem to be simply hanging in the sky. Measuring the distances to the stars has been virtually impossible without modern telescopes and measurement techniques.
We now know that the stars are at incredible distances from us. Not only is there a considerable range of distances to all of the different stars and other objects within our galaxy, but there are also billions of other galaxies. In this topic we shall investigate how to measure the distances to the stars.
Measuring how far to nearby stars - the parallax technique
The distance to a nearby star can be measured using its apparent change in position against the far distant stars over six months. During a six month period, the Earth travels halfway around the Sun. By sighting a nearby star when we are on one side of the Sun and again sighting it against the background of stars six months later, an estimate of how far it is to the star can be made.
More distant stars - using absolute brightness
The farther a star is from us, the smaller the angle through which it will seem to move as the Earth orbits the Sun. Stars that are approximately 1% of the distance across our galaxy are too far for their distances to be measured using the parallax technique.
However, astronomers have devised other methods of distance measurement, which typically rely on analysing the light of stars - or clusters of stars - to find how bright they really are, then inferring their distance by observing how bright they appear to us. This could be likened to finding how bright a torch globe really is, and then shining it towards an observer. Armed with knowledge of the real brightness, the observer could find the distance to the torch by measuring its brightness as seen from his location (the farther away it is, the fainter it would appear to him).
Very distant objects - the red shift technique
When astronomers peer toward distant galaxies, they can see very few - or none at all - of its individual constituent stars. Another technique is used which relies on an important discovery made early in the 20th century. Astronomers found that, on a large scale, the galaxies are moving apart from one another due to the overall expansion of the Universe. In addition, there is a connection between the distance to a galaxy and the speed at which it is moving away from us: the more distant galaxies are receding more quickly.
The speed of recession from us can be found by observing the galaxy's light: by measuring how much the light is shifted toward the red end of the spectrum, it is possible to find its speed (a galaxy with blue-shifted light would be approaching us). The distances to galaxies can therefore be inferred using this technique.
Light years
Stars and other distant objects are so far away that we do not measure their distances in kilometres or even billions of kilometres, but in "light years". A light year is the distance that light can travel through space in one year. Light travels at 300 000 km/sec and over a year this is equivalent to 9.5 trillion (thousand billion) km!
The nearest star Alpha Centauri, is 4.3 light years from Earth. The furthest object yet found is a quasar, 12 billion light years away. That is, the light has taken 12 billion years to get to us! This quasar probably does not even exist any more. Astronomers like to say that they are not looking though space at these distant objects, but back in time.
Re:Measuring distance of the stars (Score:1)
>
>The furthest object yet found is a quasar, 12 billion light years away. That is, the light has taken 12 billion years to get to us! This quasar probably does not even exist any more. Astronomers like to say that they are not looking though space at these distant objects, but back in time.
The other interesting implication is that if you want to know what that quasar looks like today, look around.
The centers of our galaxies may merely be the burned-out cinders that were once quasars. A lot can change in 10-15 billion years.
I missed something (Score:1)
Re:But what I don't understand is.... (Score:1)
Re:But what I don't understand is.... (Score:1)
On the subject of the universe... (Score:4, Interesting)
Where did everything come from? Don't say, "the Big Bang." To say that everything came from the Big Bang is like saying babies come from maternity wards--true in a narrow sense, but it hardly goes back far enough. Where did the stuff that went "bang" come from? What was it? Why did it bang?
Re:On the subject of the universe... (Score:1)
Plasma Universe (Score:2, Interesting)
Essentially, their theory says that the universe is criss-crossed with plasma strings, which celestial objects cluster around. This forms groupings of galaxies, clusters, superclusters, etc. Its advantage in regard to this article is that this theory allows for objects older than the 'Big Bang', since it never occurred.
For more information about Alfven: http://public.lanl.gov/alp/plasma/people/alfven.h
Re:Plasma Universe (Score:2, Informative)
Re:Plasma Universe (Score:3, Interesting)
Overall the plasma cosmology theories are scientific failures. They cannot explain Olber's paradox ("Why is the sky dark?"), which is a pretty damning failure. They do not predict the existence of the cosmic microwave background, nor explain it's spectrum and uniformity. They do not explain the Hubble redshift. They do not explain why distant galaxies look different than nearby galaxies. They do not predict or explain the ratios of the primordial elements.
Re:Plasma Universe (Score:1)
1) Olber's paradox: According to plasma theory, the universe is filamentary. We live in a relatively dense area of space, so there will be more light nearby than far away.
2) Cosmic microwave background: Plasma sources can absorb and reemit microwaves. Since the direction is random, it will quickly reach uniformity.
As for the others, the Big Bang does no better.
Re:Plasma Universe (Score:2)
In case #1, the universe cannot be finite unless we are at its very center with extremely high precision. This is very unlikely, verging on divine intervention.
For case #3, the necessary physics to rework the cosmos on a grand scale has never been observed. Thus we can rule it out.
This leaves case #2: creation in the recent past, followed by expansion.
This is completely wrong. For two regions of space to reach thermal equilibrium, they must have been exchanging photons for hundreds of times the lightspeed travel time between them. For the opposite sides of the visible universe--at least 10 billion light years--they would have had to be thermalizing with each other for at least hundreds of billions of years. Since no objects appear to be that old, we can rule out that possibility. A hot/dense genesis + expansion makes many quantitative, testable predictions. It predicts that the universe should have been in good equilibrium in the past, and thus that its composition should be fairly uniform in all directions: this is observed. It predicts that photons that brought about thermal equilibrium should have been expanded into a low-energy radiation field with high uniformity and a perfect Planckian spectrum: this is observed. It predicts that if you look a particular distance in any direction, that the galaxies you see will have the same apparent age: they do. It predicts that nearby galaxies should look older, while distant galaxies should look younger: they do. It predicts that isotopes should have particular relative abundances from the epoch of thermonuclear equilibrium: they do. It predicts that stellar and fluorescent nebula light will not be highly polarized: it isn't. (In contrast, plasma cosmology predicts extremely large magnetic fields that would strongly polarize nearly all light sources.)The magnetic field problem is one of the more damning flaws in plasma cosmology. The theory holds that stars and galaxies are moved as strongly by electromagnetism as by gravity. Such magnetic fields would have a variety of trivially observable consequences: those consequences are not observed even slightly. Moreover, galactic collisions would be *spectactular* events, akin to a solar flare on a galactic scale, and no observed galaxy collision has shown appreciable magnetic phenomena.
Plasma cosmology is simply unphysical on every scale, predicting things that are not observed, and failing to predict things that are observed.
Article (Score:2, Interesting)
The preprint of their article is available here [lanl.gov] if anyone wants to take a look.
Shape.. (Score:1)
I don't know how we got to estimate universe age (I'd like someone to tell me btw).
But if it is not based on geometric obervations but rather.. I don't know.. actual background radiation or something...
Than maybe the universe age isn't the only thing to consider if we see an apparently 'too old' galaxy, but rather a funny shape issue.
I was precisely trying to find some clues as how to find 'observable evidences' for a funny shaped Universe that 's why I thought this might be one.
If our Universe is like a 3d surface bending on a 4th (geometric, not time) dimension (it's still 3d but it is closed over itself like a sphere for example). then I expect som funny things to happen:
A star could glow, its wave front should expand sphericaly ad infinitum to the point its energy density is so low it's undetectable (too far) losing a lot of energy on its way (because of objects on its way), but then, it should a t a time of its travel reach the universe 'equator' (if Universe doesn't expand faster than light, but I don't think it does since i can see stars) and then starts to contract again until it reaches its oposite point on the surface. there, it should interfere with itself and continue its way but inverted.
On its way back, it could then appear to be a regular star, although it would in fact be a 'mirror image' of it.
Wouldn't that image lie on its age/distance ? (not sure how we really know its age/distance right now, so it might be a dumb supposition.. I really don't know). Anyway... it could be interesting toobserve such a star because it would contain information of the whole universe