i know what i know if you know what i mean

[MyHeadHurts]

i dont know if i can explain what it is i dont know....you know?
but here goes
i read recently that it has been determined that the milky way was among the first galaxies to form. now astronomers look at objects very far away and say that galaxy is 13 or 14 billion lys away. if the milky way was formed at about the same time and the universe was a good bit smaller at that time, then that galaxy was alot closer then 13 or 14 billion lys. would not the light from 13 or 14 billion years ago have already passed us by? in other words....how can you see light 13 or 14 billion light years ago if when that light turned on the universe was just a few million lys accross?
does that make sense?

[antoniseb]

Originally posted by MyHeadHurts@Aug 24 2004, 08:55 PM
how can you see light 13 or 14 billion light years ago if when that light turned on the universe was just a few million lys accross?
does that make sense?

Suppose that when the light was emitted, we were moving away from the source of the light at nearly the speed of light...

[StarLab]

Space stretches...photons don't.

[aries_4_5_48]

....I'm not certain, but I get the impression from your question that when you say 'formed', everything stopped, formation occured, light was emitted, and things took off again. If this happens to be the case, rethink remembering that everything is......

[David S]

well, those galaxies are constantly emitting light. So even if the first photons that galaxy emitted have passed us by (and they undoubtedly have), the galaxy is still generating photons continuously.

[aries_4_5_48]

.....to think about, but lose the headache first: 1) get a balloon, 2) put a little mark on the end opposite of where you blow it up, 3) 1/2 way down one side of your balloon make another mark, 4) you are sitting on the first mark you made, your brother is on the second mark, he can ride his bike from where he is, to where you are in X-amount of time (he's ridden THAT distance before), 5) at the same instant he starts riding you start blowing up the balloon, 6) will he get home in the amount of time (X) that he said he would, or will it take him longer?

"Understanding is of a higher order than accuracy." :unsure:

[xXxDarkSkyNitexzxXx]

i agree with what antoniseb says

[MyHeadHurts]

ok so you guys have no idea either
anton.....we're not moving away at nearly the speed of light from the source
starlab...space dont stretch that fast...not even close
aries...what the heck are you talking about?
astro.....yes the galaxies are still generating photons....duh
aries...i hate that balloon example...but its a good way to look like you know what your talking about...not that i do...but i aint faking it
seems to me that you could never see to the start of the age of light or the end of the age of darkness...only to the age of the milky way plus the distance between us and it minus the years between then and now

thou shall not add thy speed to that of light
:blink:

[antoniseb]

Originally posted by MyHeadHurts@Aug 26 2004, 03:37 PM
anton.....we're not moving away at nearly the speed of light from the source

Actually, we are. Why else would there be a red shift that increases the wavelength of light by a factor of seven or eight when we view these objects?

[StarLab]

Good point, Anton!
Score: Anton, 1, MHH, 0
But, Anton, redshift, as it applies to galaxies rather than stars, is coming under serious doubt these days...people are starting to rethink Einstein's Cosmological Constant...so I will subtract half a point.

[antoniseb]

Originally posted by StarLab@Aug 27 2004, 12:09 AM
redshift, as it applies to galaxies rather than stars, is coming under serious doubt these days

Not outside the alternative theories section. Also, Einstein's cosmological constant does not cause non-velocity cosmological redshift. Where did you get the idea that it does? I'm not looking for any points you might be awarding, but I do want the record set straight, and junk ideas to be rapidly debunked. Otherwise naive younsters like yourself might take them seriously.

[StarLab]

I do not take anything seriously until I find out whether it's right, or wrong, or undecided. So go ahead, lecture me; I wanna hear this.

[antoniseb]

Originally posted by StarLab@Aug 27 2004, 01:57 PM
I wanna hear this.

This is a broad topic. I am pressed for time. If you want to take a look at a non-velocity cosmological redshift theory, try looking through the papers pointed to in the CREIL thread. I think even someone as new to all of this as you will see holes in their theories.

[aries_4_5_48]

.....I'll never use the balloon example again I swear. The question I asked was: would it arrive as expected, or later, period. That's a concept, not an answer, I think..... :blink:

[bunny]

I see what you mean but there are a lot of assumtions being made.
Here is how I see it.

Say a star is 4 light years away.

Q:Has the light taken 4 years to reach us?

A: Only if the distance between us and the star is exactly 5.85*10^12 miles away and that the distance has not changed. In fact what we see is an image of the star as it was fours years ago in the place it was four years ago.

( c=constant 186000miles/sec I am only using rough figures here)

The two bodies are moving away from each other, say at 0.1 of a lightyear/year

Q: How long has the light taken to reach us after a year?

A: we are now 6*10^13 miles away and the light has taken a tenth longer to reach us. in a year we are now 4.1 lightyears away.

If you plug in the numbers for the actual rate of expansion and the apparent distance between them you should be able to work out the distance the bodies were apart when the star started shining.

[Bosco D. Gamma]

Originally posted by MyHeadHurts@Aug 24 2004, 08:55 PM
i read recently that it has been determined that the milky way was among the first galaxies to form. now astronomers look at objects very far away and say that galaxy is 13 or 14 billion lys away. if the milky way was formed at about the same time and the universe was a good bit smaller at that time, then that galaxy was alot closer then 13 or 14 billion lys. would not the light from 13 or 14 billion years ago have already passed us by? in other words....how can you see light 13 or 14 billion light years ago if when that light turned on the universe was just a few million lys accross?
does that make sense?

i read recently that it has been determined that the milky way was among the first galaxies to form. now astronomers look at objects very far away and say that galaxy is 13 or 14 billion lys away.

13 or 14 billion lys away is both the distance and estimated age of the universe.
They do NOT say "that galaxy" is THAT far away since the age of galaxies didn't start until AT LEAST 1 billion yrs after and perhaps 2 or 3 billion.

You forgot red shift. Quasars are some of the most distant objects known and their red shifts are indeed close to speed of light.

Can you give a URL for the story about the age of the Milky Way ?

"..if when that light turned on the universe was just a few million lys accross?"
the universe was NOT a "few million lys across" The age of light begain a few million years after the big bang. The age of galaxies began 1 to 3 billion years after the big bang.

Then there is Big Bang / Inflation theory. Which summed up = big bang, universe expands at superluminal speeds, slows down and continues to expand at much more sedate rate.

Even without that explaination, objects are moving away from each other as the very fabric of space expands, the accumulated effect of that is the more distant objects are expanding away at a faster rate ... and they are constantly emitting photons .. soooooo... I don't see the problem, perhaps if you can phrase your question differently.