Pristine relics of the Big Bang spotted

[Vulagr]

For the first time, astronomers have discovered two distant clouds of gas that seem to be pure relics from the Big Bang. Neither cloud contains any detectable elements forged by stars; instead, each consists only of the light elements that arose in the Big Bang some 14 billion years ago. Furthermore, the relatively high abundance of deuterium seen in one of the clouds agrees with predictions of Big Bang theory.


Just after the Big Bang, nuclear reactions created the three lightest elements – hydrogen, helium, and a tiny bit of lithium. Stars then converted some of this material into the heavy elements such as carbon and oxygen that pepper the cosmos today.



But no-one has ever seen a star or gas cloud made solely of these three Big Bang elements. Instead, all known stars and gas clouds harbour at least some "metals", the term astronomers use to describe any element, even carbon and oxygen, that is heavier than helium.

http://physicsworld.com/cws/article/news/47769

So my questions are this; why does it have to be a "Relic" of the big bang? Couldn't these gasses have gathered together just recently, so to speak? If they were true "Relics" of the big bang, wouldn't we be able to date the clouds back to the time of the big bang and if we are able to date the clouds, would that dispel that they've existed since the big bang?

 

[sojourner]

1) you quoted the part that explains why they think these clouds are remnants of the big bang. To recap: no contaminants.
2) why would being able to date the clouds dispel the fact they originated with the big bang???

 

[Vulagr]

2) why would being able to date the clouds dispel the fact they originated with the big bang???

Because couldn't it be possible that these clouds just came into existence relatively recently and are far younger than the universe?

 

[MANT!]

Damn I thought they'd found a prehistoric atomic bomb...

 

[sojourner]

2) why would being able to date the clouds dispel the fact they originated with the big bang???

Because couldn't it be possible that these clouds just came into existence relatively recently and are far younger than the universe?

The article explains why they don't think this is the case. If they had formed later there would be more trace elements.

 

[Lindley]

2) why would being able to date the clouds dispel the fact they originated with the big bang???

Because couldn't it be possible that these clouds just came into existence relatively recently and are far younger than the universe?

Keep in mind that in astronomy, distance is directly related to age. The further away something is, the longer ago it emitted the light we are now seeing.

That's why we have an observable universe. There's more to it, but anything further away has not had time to get any light to us since the Big Bang.

 

[RoJoHen]

That's why we have an observable universe. There's more to it, but anything further away has not had time to get any light to us since the Big Bang.

At the risk of this being a stupid question, does this mean that new things could potentially start appearing in the sky the more time that goes by? Does that question even make sense?

 

[Finn]

^Yeah, but they would be really dim....

 

[sojourner]

That's why we have an observable universe. There's more to it, but anything further away has not had time to get any light to us since the Big Bang.

At the risk of this being a stupid question, does this mean that new things could potentially start appearing in the sky the more time that goes by? Does that question even make sense?

only in the sense that your watching a movie of what happened billions of years ago.

We won't go out tomorrow night and suddenly see a galaxy in the night sky.

 

[RoJoHen]

That's why we have an observable universe. There's more to it, but anything further away has not had time to get any light to us since the Big Bang.

At the risk of this being a stupid question, does this mean that new things could potentially start appearing in the sky the more time that goes by? Does that question even make sense?

only in the sense that your watching a movie of what happened billions of years ago.

We won't go out tomorrow night and suddenly see a galaxy in the night sky.

But what if tomorrow night is when the light gets here?!

And no, I don't mean we'll see a bunch of crazy stuff popping up in the sky. But say, for example, tomorrow night the light from a galaxy reached us for the first time...would there suddenly be another little white dot amongst all the other stars and galaxies we already see?

 

[Nerys Ghemor]

I may be wrong, but it doesn't seem likely to me that could happen with objects visible to the naked eye. (This is assuming ideal atmospheric conditions--so probably an observatory at high altitude, or better yet, one of our space-based telescopes.)

That said, it would be interesting to train a telescope on a specific spot in the sky--particularly one of those long-range ones like the one that picked up these remnants--and see if at any point anything new becomes visible. But I would think that would take hundreds of years of observations if not more.

 

[RoJoHen]

Oh, I'm sure it could probably take millions of years for such a thing to happen. I was just wondering if I was getting the science right, or if everything currently visible in the night sky is all that will ever be visible.

 

[sojourner]

And no, I don't mean we'll see a bunch of crazy stuff popping up in the sky. But say, for example, tomorrow night the light from a galaxy reached us for the first time...would there suddenly be another little white dot amongst all the other stars and galaxies we already see?

No, because that would mean that galaxy just appeared where it is fully formed. It's not like someone turned on a light bulb millions of lightyears away. You would first see (if you had a powerful enough telescope) someone bringing in the lamp, plugging it in, screwing in the light bulb and then flipping the switch. So to speak.

Your question is like asking if the sun suddenly appears in the noon day sky.

 

[YellowSubmarine]

But if the galaxy is moving at warp 9, it might make a Picard Manuever and appear in the sky before we see it forming!

 

[Kai Winn]

That's why we have an observable universe. There's more to it, but anything further away has not had time to get any light to us since the Big Bang.

At the risk of this being a stupid question, does this mean that new things could potentially start appearing in the sky the more time that goes by? Does that question even make sense?

only in the sense that your watching a movie of what happened billions of years ago.

We won't go out tomorrow night and suddenly see a galaxy in the night sky.

Maybe a nova sometimes. The number of visible far away galaxies should decrease over time however, if the universe is actually expanding faster than the speed of light, and they vanish one after another behind the light horizon. I've got a problem with the expanding universe however, if a 13 billion light years away galaxy is redshifted, does it not mean it was withdrawing 13 billion light years ago, and we don't know where it's moving to right now? And why is Andromeda an exception moving towards the Milky Way?

 

[Lindley]

And why is Andromeda an exception moving towards the Milky Way?

Galaxies aren't really rushing away from each other per se. The space between them is expanding; thus, the more space between two galaxies, the faster they appear to be moving away from each other. But on a more local scale, galaxy movement is not so dramatic.

As you blow up a balloon, the atoms in the rubber on one side rush away from the atoms in the rubber on the other side of it. But a collection of atoms right next to each other will still interact in fairly random ways, bouncing off each other etc.

 

[Manticore]

And why is Andromeda an exception moving towards the Milky Way?

Galaxies aren't really rushing away from each other per se. The space between them is expanding; thus, the more space between two galaxies, the faster they appear to be moving away from each other. But on a more local scale, galaxy movement is not so dramatic.

As you blow up a balloon, the atoms in the rubber on one side rush away from the atoms in the rubber on the other side of it. But a collection of atoms right next to each other will still interact in fairly random ways, bouncing off each other etc.

As well, Andromeda is part of our local cluster, so we're all in the same local system. IIRC, it's the clusters, more, that are moving apart.

 

[Silvercrest]

But if the galaxy is moving at warp 9, it might make a Picard Manuever and appear in the sky before we see it forming!

It can't do that. We're a prewarp culture, so to perform a visible Picard Maneuver would violate the Prime Directive.

 

[Davros]

For some reason, when I saw the thread title I could not help but think of Galactus's space ship.

 

[Lindley]

And why is Andromeda an exception moving towards the Milky Way?

Galaxies aren't really rushing away from each other per se. The space between them is expanding; thus, the more space between two galaxies, the faster they appear to be moving away from each other. But on a more local scale, galaxy movement is not so dramatic.

As you blow up a balloon, the atoms in the rubber on one side rush away from the atoms in the rubber on the other side of it. But a collection of atoms right next to each other will still interact in fairly random ways, bouncing off each other etc.

As well, Andromeda is part of our local cluster, so we're all in the same local system. IIRC, it's the clusters, more, that are moving apart.

And on a larger scale, the clusters would appear to be in the same local system; it's the superclusters that are moving apart.

It's all about scale. Be thankful the "rushing away" effect is only really observable on cosmological scales so far....one End of The Universe theory, the "Big Rip", suggests that someday it could become observable on smaller scales, until finally our very atoms would be rushing apart.