Hubble Telescope

[jbh186 0]

http://www.cnn.com/2010/TECH/space/01/05/hubble.new.galaxies/index.html

This article got me thinking. If Hubble is looking "back in time" 13 billion years, with a little more advanced technology, what happens if it looks back 13.8 billion years? Would it be possible to see the big bang?

This astronomy stuff makes my head hurt...

I don't want this to go to SC, so lets keep the Big Bang vs creation out of it.

[cocheese 0]

Would it be possible to see the big bang?

Yes but like scrambled porn, it's hard to differentiate between an ear and what you really want to see.

[AggieDave 6]

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what happens if it looks back 13.8 billion years?

It might catch the birth of Airtwardo?

--"When I die, may I be surrounded by scattered chrome and burning gasoline."

[dzdiva 7]

"It's not just a daydream if you choose to make it your life..."

[billvon 3,006]

>This article got me thinking. If Hubble is looking "back in time" 13
>billion years, with a little more advanced technology, what happens if it
>looks back 13.8 billion years? Would it be possible to see the big bang?

We can see it now; we call it "cosmic background radiation." We're inside the sphere of expanding timespace that is the universe, so we can't see it from outside (of course.) But from inside we can see the afterglow of the edge, and it's pretty uniform in all directions.

[lawrocket 3]

I've got some questions, bill:

If the universe was static, then the 13 billion years would be the distance 13 billion years ago.

But since the universe is expanding, we can work out an estimate. Hubbell's constant being measured by Hubble scientists at roughly 70/km/sec/mpc - a megaparsec being 3.26 million light years, we'd see about 4,000 megaparsecs in 13 billion light years.

This would put the expansion of these items being at 280000 km/sec, right? The speed of light is 299792.458 km/sec. This means that the 13 billion year old light is expanding at .934 the speed of light - at an ever increasing ratio.

Now - being not mathematical enough to work out the differential equations (I admit it), when the light being received was sent, couldn't that distance have been, oh, 8 billion light years away when it was emitted but thanks to expansion take 13 billion light years to get here?

Also, could we be seeing the other side of the universe?

Finally, I do not believe that Hubble's constant is limited to the speed of light. This means that at, say, 6000 megaparsecs, the light from those objects (hypothetically on the other side of the universe) will NEVER reach us.

Am I wrong in these questions?

My wife is hotter than your wife.

[Jbag 0]

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>This article got me thinking. If Hubble is looking "back in time" 13
>billion years, with a little more advanced technology, what happens if it
>looks back 13.8 billion years? Would it be possible to see the big bang?

We can see it now; we call it "cosmic background radiation." We're inside the sphere of expanding timespace that is the universe, so we can't see it from outside (of course.) But from inside we can see the afterglow of the edge, and it's pretty uniform in all directions.

wouldnt that be an interpretation of what we think we see? although i like the thought of seeing the end of the world, it makes me smile :)

IHYD

[lawrocket 3]

It's neat that people were looking for it but couldn't get any clear readings because of the background static. Then they figured out the static was what they were looking for. I think that was the story...

My wife is hotter than your wife.

[warpedskydiver 0]

No in the greater sense you are correct, you might want to refer to;

When we are looking at the age of universe we don't actually need any velocity because the Hubble constant itself is in the units of inverse time.

So, t=1/H. Of course, it can't be that simple ;) because the units of the Hubble constant are quite strange.

km/s/Mpc???? Well, if we know the number of km in a Mpc, we can change units. Like Sara said, 1Mpc = 3.09x19 km

So, if we multiple the Hubble constant by the number of Mpc in a km (Mpc/km) we will be left with units of s^-1.

If H=35km/s/Mpc = 35/3.09e19=1.13e-19 s^-1
If H=71km/s/Mpc = 71/3.09e19=2.3e-18 s^-1
If H=142km/s/Mpc=142/3.09e19=4.6e-18 s^-1

Now, t=1/H

For H=35: 1/H=8.85e19 s
For H=71: 1/H=4.35e18 s
For H=142: 1/H=2.17e17 s

Finally, we can divide by the number of seconds in a year to have a reasonable answer. Like Sara (classmate) mentioned, there are 3.16e7 seconds in a year.

For H=35: T=2.8e10 years = 28 billion years
For H=71: T=1.37e10 years =13.7 billion years
For H=142: T=6.9e9 years = 6.9 billion years


The important thing to notice here - as H increases, the age of the universe decreases.

Hubble's Law, used to find the distance of a galaxy if its recession velocity can be measured, uses the recession velocity (measured in km/s) and divides it by Hubble's constant (measured in Mpc) to attain the distance to the galaxy.

in other words:
d = v/H = 10000 / 70 = 142.86Mpc


Yes, I wrote the above

[warpedskydiver 0]

All due to a pair of stoners in New Jersey, go figure...

[SkyBastard 0]

clearly this is wrong.

do it again but different. 6/10 for effort.

Dude #320
"Superstitious" is just a polite way of saying "incredibly fucking stupid".
DONK!

[warpedskydiver 0]

[warpedskydiver 0]

I was only a "B" student, I scored 0.70pts under an "A"

So out of 1000pts I only scored 899.30pts

I guess I should have tried harder.

That was a pretty tough class.

[warpedskydiver 0]

I was waiting for the usual suspects to tell me how wrong I am, so I could laugh at them.

Dammit!

[jbh186 0]

As much as I appreciate that answer, WTF does all that mean?

[warpedskydiver 0]

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As much as I appreciate that answer, WTF does all that mean?

That Hubble's constant was not as precise as needed.

He did a great job given the tools and previous work done by others, but now we know it is just not good enough to use it alone.

We are talking about distances that are so mind blowing that a simple but slight error compounds to a distance that is immense.

I could try and explain it further but I really don't want to write that much.

If you really need more information I can refer you to some excellent texts and resources.

[warpedskydiver 0]

That the universe is in excess of 13.8 Billion years old.

Probably closer to 15 billion.

[wolfriverjoe 1,523]

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As much as I appreciate that answer, WTF does all that mean?

#1 The unuverse is really really big.

#2 The universe is really really old.

#3 Astrophysics is really really complicated.

#4 Warpedskydiver isn't dumb

"There are NO situations which do not call for a French Maid outfit." Lucky McSwervy

"~ya don't GET old by being weak & stupid!" - Airtwardo

[SkyBastard 0]

i'm sitting in my little studio flat now, it's a small flat at the best of times, but now, thinking about it in relation to the rest of the universe, well, it sure hasn't got any bigger.

Dude #320
"Superstitious" is just a polite way of saying "incredibly fucking stupid".
DONK!

[billvon 3,006]

>when the light being received was sent, couldn't that distance have been,
>oh, 8 billion light years away when it was emitted but thanks to expansion
>take 13 billion light years to get here?

Yes, definitely.

>Also, could we be seeing the other side of the universe?

Yes, that's the most likely explanation; the background radiation is fairly consistent throughout the visible universe, implying that we're seeing all of the 'sides' of the expanding wavefront that is our universe.

>Finally, I do not believe that Hubble's constant is limited to the speed of
>light. This means that at, say, 6000 megaparsecs, the light from those
>objects (hypothetically on the other side of the universe) will NEVER reach
>us.

To a static observer, though, the light still propagates normally through any given section of space. So we'll eventually always see it - but it may be so red-shifted that we can't detect it any more.

[ryoder 1,590]

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i'm sitting in my little studio flat now, it's a small flat at the best of times, but now, thinking about it in relation to the rest of the universe, well, it sure hasn't got any bigger.

Or perhaps your flat really is expanding,
but you are expanding at the same rate, so it seems the same size.

"There are only three things of value: younger women, faster airplanes, and bigger crocodiles" - Arthur Jones.

[lawrocket 3]

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As much as I appreciate that answer, WTF does all that mean?

That Hubble's constant was not as precise as needed.

He did a great job given the tools and previous work done by others, but now we know it is just not good enough to use it alone.

The Hubble telescope had some research back ten years ago that attempted to narrow down the value of Hubble's Constant. That's where I got the 70/km/sec/mpc figure (though the scientists themselves agreed that it could be between 50 and 100 - still, they view it as a narrowing to 10%, a substantial increase.

There is something of note, however, is that the team that sought to quantify the constant measured that the age of the universe could be as little as 12 billion years. If the universe had expanded rapidly at the beginning, then the universe would be younger. On the other hand, if the acceleration was fairly constant then the universe may be far older - up to 15 billion years old!

It seems notable to me that there may now be objects up to 20 or 30 billion light years away at an opposite edge of the universe. Or maybe these objects 13 billion light years away were already a couple billion years old when the light we see now was created.

Fascinating things!

My wife is hotter than your wife.

[lawrocket 3]

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To a static observer, though, the light still propagates normally through any given section of space. So we'll eventually always see it - but it may be so red-shifted that we can't detect it any more.

At that distance, though, the universe is expanding at greater than the speed of light. Doesn't this mean that the light source there is never seen because light is being expanded away more quickly than it can move toward us? Kind of like an airplane traveling at 100 mph airspeed into a 120 mph headwind - it will never be able to move forward relative to a static ground observer.

My wife is hotter than your wife.

[quade 4]

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At that distance, though, the universe is expanding at greater than the speed of light.

That's probably an incorrect assumption.

quade -
The World's Most Boring Skydiver

[shropshire 0]

Let me put it like this [clears throat].....

Just remember that you're standing on a planet that's evolving
And revolving at nine hundred miles an hour,
That's orbiting at nineteen miles a second, so it's reckoned,
A sun that is the source of all our power.
The sun and you and me and all the stars that we can see
Are moving at a million miles a day
In an outer spiral arm, at forty thousand miles an hour,
Of the galaxy we call the 'Milky Way'.
Our galaxy itself contains a hundred billion stars.
It's a hundred thousand light years side to side.
It bulges in the middle, sixteen thousand light years thick,
But out by us, it's just three thousand light years wide.
We're thirty thousand light years from galactic central point.
We go 'round every two hundred million years,
And our galaxy is only one of millions of billions
In this amazing and expanding universe.

The universe itself keeps on expanding and expanding
In all of the directions it can whizz
As fast as it can go, at the speed of light, you know,
Twelve million miles a minute, and that's the fastest speed there is.
So remember, when you're feeling very small and insecure,
How amazingly unlikely is your birth,
And pray that there's intelligent life somewhere up in space,
'Cause there's bugger all down here on Earth.

THE END

(.)Y(.)
Chivalry is not dead; it only sleeps for want of work to do. - Jerome K Jerome