Olbers paradox

[robinson]

Why do we not observe any of the obscuring dust ever glowing as bright as the stars the dust obscures?

And yes, this has been splained many times, but never answered

[robinson]

It’s this part that has bugged me for like a decade now

While dark clouds could obstruct the light, these clouds would heat up, until they were as hot as the stars, and then radiate the same amount of light.

[robinson]

There are no images from the Universe that show any obscuring dust ever glowing as bright as stars

In our own Galaxy the obscuring dust has been absorbing star light for a very very long time, but none of it is glowing with light like the stars behind the dust

I don’t expect you to know the answer, but I enjoy thinking about this sort of thing

[robinson]

Olbers paradox was explained away by the Big Bang expanding Universe theory

But none of that matters to our local and very bright Milky Way

Why isn’t the Milky Way glowing as bright as the sun?

The answer is the obscuring dust

In the paradox that dust is presumed to glow as bright as the stars it obscures, meaning the dust can’t be the reason for the dark sky

But at the same time the dust is explained as the reason the Milky Way looks dark

It doesn’t add up

[Bruce]

Each particulate of dust can only emit a tiny fragment of thiny fragment of light it absorbs, so why would you expect it to be as luminous as a star?

By the same logic, the moon should be a bright as the sun because it's been absorbing and reflecting the light of the sun since its formation, so it should be super hot, right.

Space is could and vast. Plenty of time, distance and emptiness for light to disperse and fade.

[robinson]

Or maybe the universe just plain isn't infinite and is on the average rather sparse?

That may be, but it isn't what is bugging me. Olbers paradox really isn't the issue, it's the assumption contained in it, mentioned in post #2

While dark clouds could obstruct the light, these clouds would heat up, until they were as hot as the stars, and then radiate the same amount of light.

Here's another version of it

obscuration by dust ===> distant stars are blocked out and appear fainter. Turns out this won't work because dust, if it absorbs energy will heat up and re-radiate the energy. This means that the Universe will still be filled with the same amount of radiation, the dust acts simply as a go-between so to speak.

https://web.archive.org/web/19990506085 ... lbers.html

So one reason explaining the dark sky is handwaved away by saying dust can't be the cause of the dark sky, because (see above)

Space is could and vast. Plenty of time, distance and emptiness for light to disperse and fade.

Again, that may be the case, but I am talking about something right here at home, that has nothing to do with vast distances, the expanding Universe, the Big Bang or a lack of stars. The Milky Way is so dense along the plane of it, especially near the center, that it should glow as bright as the sun. It should be visible during the day. Looking along the galactic plane meets the condition of a star at every point of sight, it's literally a wall of solid starlight.

Infrared isn't blocked by dust so here is an image of what I mean

mw in infrared.png

https://www.scientificamerican.com/gall ... -infrared/

It doesn't look like that in the visible, because of dust obscuring the light. In fact there is no dust in the Milky way glowing like starlight, no matter how much light is being absorbed. Dust shows up as dark obscuring matter.

Is it a time thing? Not enough time has passed for any dust to start glowing? (Olbers paradox again)

Of course not. So what is it?

[ed]

Robinson, you keep this up I'm going to hunt you down and kick you in the nut-sac.

Are we clear?

[Fid]

Goddam bro all your weaponry and all you threaten is a kick in the most likely non-existant ball sack.
Cannons...I'm pretty sure you've got one.

[robinson]

Ed, if you spent just a tiny amount of your infinite life learning about interstellar dust, you might get an aha!

Instead of raging like an impotent deity

[Bruce]

I don't know what else to tell you except maybe that astrophysics doesn't work the way you think it works? Also, Olber lived during a time when everyone thought the universe was static and finite. In fact his paradox was an argument against the thinking of the day.

Do have any other concerns about outdated ideas?

Do you worry about what might happen if Atlas shrugged?

[ed]

Ed, if you spent just a tiny amount of your infinite life learning about interstellar dust, you might get an aha!

Instead of raging like an impotent deity

Let me be crystalline clear on one point ...

I created fucking dust precisely so I COULD ignore it.

That is a divine truth: Ignore the goddamn dust.

And here you go and what do you do?

Start a thread about the dust.

And the nut-sac kick is because it is far more gratifying to make foot to nut-sac contact than it is to shoot someone.

[robinson]

Olber’s paradox is considered one of the most interesting physics problem in science

https://www.gregschool.org/gregschoolle ... 6hj4-pzpcf

No less than Edgar Poe and Lord Kelvin both “solved” it, and it has interested generations of astronomers and philosophers of natural science

All of it, every last bit of the solution involves dismissing the obvious answer, which is the source of the paradox itself

For the barely interested, the obvious answer is the light is dimmed by dust and gas (and ions and cold plasma) that is everywhere in space. That’s why the sky is dark at night, not blazing with the light of 1,000,000,000,000,000,000,000,000 stars, or a "1" with 24 zeros after it (1 septillion in the American numbering system; 1 quadrillion in the European system).

(This is considered a gross underestimate)

That’s just the stars we can see, nobody has any idea how many are out there that the light hasn’t reached us yet

[robinson]

The paradox comes from the assumption that “obscuring dust would glow as bright as the stars”, which is the source of the problem. If dust dims the light so the sky is dark, there is no paradox.

Looking at the local galaxy, the one we are in, it’s quite obvious it is dark because dust obscured the light.

If you explain this by saying there hasn’t been time for the dust to be heated up by all the star light it is blocking, this just raises another question.

[robinson]

Our galaxy is between 10 and 12 billion years old, though the oldest stars in it might be 13 billion years old.

If the obscuring dust is going to glow as bright as the stars, it’s taking it’s sweet time about it

[robinson]

When they zoomed in with the Hubble telescope, the center of our galaxy is not only solid with stars, there are so many the stars are blocking the stars behind them. It’s a solid field of stars, no empty spaces at all. (Even if it was only 10% full it doesn’t change the problem, it would be 10% as bright as the sun, which is really bright)

So just 30,000 light years from us is a solid wall of bright stars, no expanding Universe or “the light hasn’t reached us”, or any of the solutions to the paradox proposed are causing it to be very dim

It’s simply dark cold gas and dust blocking the starlight

But the assumption about star light is if it was just obscuring matter, that would glow as bright as the stars, which it doesn’t

No where do we see dust glowing like that, even after 10 billion years

So what’s up with that?

[robinson]

To be crystal clear about it

My wonderment is over the claim “it can’t be dust because it would glow as bright as the starlight”

Which is fucking absurd

[robinson]

Robinson, you keep this up I'm going to hunt you down and kick you in the nut-sac.

Are we clear?

[robinson]

Cosmic fart

[robinson]

Well, I guess nobody cares, which is par for the course

Of course

[ed]

welcome to my world

[Fid]

~~Sigh~~Such a waste of cannon. Ya know they filled the barrels of the cannons with concrete.

[ed]

Concrete can be removed.

[robinson]

The answer to my question is actually known. But learning of it changes nothing.

[Bruce]

Robinson, you keep this up I'm going to hunt you down and kick you in the nut-sac.

Are we clear?

Did anyone notice toward the end of the clip, after the particulates started to slow down, the clouds appeared to become gravitationally pulled in by the surrounding stars? Is this an optical illusion? How far away are those stars from each other? How fast was the cloud moving?

[robinson]

This might help explain what you are seeing

https://en.wikipedia.org/wiki/V838_Monocerotis

https://upload.wikimedia.org/wikipedia/ ... 9-2006.gif

[robinson]

[robinson]

If it wasn’t for the dust and gas obscuring the light, the center of the andromeda galaxy would be far brighter that the moon

[robinson]

Dust and gas absorbs visible light, but radiates in infrared

Which is why it will never “glow as bright as the stars”

The claim that the sky is dark because of the expansion of the Universe, or because it is too young, does not explain why our galaxy is so dark

[robinson]

Dust and gas absorbs visible light, but radiates in infrared

Which is why it will never “glow as bright as the stars”

The claim that the sky is dark because of the expansion of the Universe, or because it is too young, does not explain why our galaxy is so dark

[robinson]

If dust and gas did not absorb light the sky would look like this




Except it would blind you instantly

[robinson]

Both the high energy photons, and most of the infrared are absorbed by our atmosphere

Most of the visible from distant stars is absorbed by cosmic dust and gas

[robinson]

[robinson]

The reason all the light absorbed by gas and dust never shows up, is exactly the same reason fog and a haze from pollution never glows as bright as the sunlight it blocks


Visible light that is absorbed by matter is radiated away as infrared, which we can’t see

No matter how many billions of years dust blocks starlight, it’s never going to glow as bright as starlight

Olbers paradox is based on a false idea