Size and Scale of the Universe
Discussion
So, consider this.
The observable universe has a diameter of roughly 93 billion light-years and contains around 2 trillion galaxies.
If each of those galaxies contains an average of ~200 billion stars, then the total number of stars in the observable universe is approximately 4 ×10^23. We also know that the average star in the universe is roughly half the size of our Sun, giving it an average volume of about 1.685×10^17
Multiplying the total number of stars by the average star volume: 4 ×10^23 x 1.685×10^17 = 6.74×10^40 cubic miles. This gives a rough estimate of the total volume occupied by all stars in the observable universe.
The volume of the observable universe itself is roughly: 8.5×10^70 cubic miles
Dividing the stellar volume by the total universe volume gives the fraction of space actually filled by stars:
6.74×10^40 divided by 8.5×10^70 = 1.98×10^-54
In other words, all the stars in the universe occupy an unimaginably tiny fraction of the universe’s volume — about:
0.000000000000000000000000000000000000000000000000000000198%
Even if we included planets, gas, and black holes, this fraction would barely change.
To put this in perspective: if we shrunk the observable universe down to the size of Earth, all the stars clumped together would occupy roughly the size of a proton. And even that proton would be broken up and scattered evenly through the Earth-sized volume.
Going further, atoms themselves are mostly empty space. An atom could be compared to a football stadium with a tiny pea at the centre representing the nucleus, surrounded by a thin cloud of electrons.
The universe is a gigantic empty bubble, with all the matter — stars, planets, and gas — making up an almost infinitesimal fraction of the space.
The universe is overwhelmingly empty, and the matter we see is just a tiny, tiny wisp floating in a vast void.
I've checked all these numbers and my reasoning with AI and yes, I believe it to be correct. 0.000000000000000000000000000000000000000000000000000000198% this number is absolutely mind blowing. Anyone want to critic my reasoning?
The observable universe has a diameter of roughly 93 billion light-years and contains around 2 trillion galaxies.
If each of those galaxies contains an average of ~200 billion stars, then the total number of stars in the observable universe is approximately 4 ×10^23. We also know that the average star in the universe is roughly half the size of our Sun, giving it an average volume of about 1.685×10^17
Multiplying the total number of stars by the average star volume: 4 ×10^23 x 1.685×10^17 = 6.74×10^40 cubic miles. This gives a rough estimate of the total volume occupied by all stars in the observable universe.
The volume of the observable universe itself is roughly: 8.5×10^70 cubic miles
Dividing the stellar volume by the total universe volume gives the fraction of space actually filled by stars:
6.74×10^40 divided by 8.5×10^70 = 1.98×10^-54
In other words, all the stars in the universe occupy an unimaginably tiny fraction of the universe’s volume — about:
0.000000000000000000000000000000000000000000000000000000198%
Even if we included planets, gas, and black holes, this fraction would barely change.
To put this in perspective: if we shrunk the observable universe down to the size of Earth, all the stars clumped together would occupy roughly the size of a proton. And even that proton would be broken up and scattered evenly through the Earth-sized volume.
Going further, atoms themselves are mostly empty space. An atom could be compared to a football stadium with a tiny pea at the centre representing the nucleus, surrounded by a thin cloud of electrons.
The universe is a gigantic empty bubble, with all the matter — stars, planets, and gas — making up an almost infinitesimal fraction of the space.
The universe is overwhelmingly empty, and the matter we see is just a tiny, tiny wisp floating in a vast void.
I've checked all these numbers and my reasoning with AI and yes, I believe it to be correct. 0.000000000000000000000000000000000000000000000000000000198% this number is absolutely mind blowing. Anyone want to critic my reasoning?
Running Through Space. Or….. The Universe in Perspective.
Got a minute? Good. Then you can understand the big picture, the Universe, once and for all, which is normally bloody difficult. The clever men from Oxford have been trying for ever and they wind up confusing us as comprehensively as the clever men from Cambridge. But I have it, we are going to run through it!
It’s easy, we don’t need any theories like Archie Medes making his bathroom floor wet or formulas from Einstein.
I will bring the Universe into easy comprehension for all, and it has never been done before. You see, IT ALL DEPENDS ON HOW BIG YOU ARE. To us humans, being too small you see, between five and six feet tall, (This is not an exact science, it doesn’t need to be.) the Universe is a vast gobblydegook of light years, and parsecs and red shifts. Only God, (If he made it) knows what it’s all about and how far it goes. Imagine now how big it would all seem to you if you were a cat, say one foot tall. Five to six times larger than it seems now, five to six times more passing the understanding, however clever a cat you were. Imagine now you are an ant, a microbe. It’s too much, it’s no go the anty-man, it’s no go Blavatsky.
Right, on we go. Microbes, ants, cats and people are all too small to understand the vastness of space so let us do a ‘thought experiment.’ No test tubes, no sparks on shiny balls, no hair all over our face. Einstein did them all the time and are we going to admit he would be any better at it than us. No.
How big is space? That’s our experiment.
Here we go. Put on your running shoes. The sun is one hundred million miles away from Earth. Near enough. If you want exact there are special books you can get, take a large bag to carry them.
WE BECOME HUGE GIANTS, now we can understand the vastness of space, at last. So we imagine we are two hundred million miles tall, and every long step we take is one hundred million miles long. It’s a familiar distance, we don’t do it every day but it’s roughly the distance from the Earth to the Sun. What a stride! What huge trousers. Now to start running around the Universe.
We step out from Earth, bonk, one step and we are on the Sun. Bit hot, let us trot off to the furthermost planet in our Solar System, namely Pluto. Forty steps, a half minute stroll, not so far as the paper shop, and we are standing, smiling broadly on the planet Pluto.
Fine view from here, lots of stars, all over the place, they are our gang. The Galaxy of which the Sun is a member. We are called collectively The Milky Way. There are none very close, bit off-putting, might be in for a bit of a long walk here. We spot the closest to us, it has a name plate, Alpha Centauri, sounds posh, we’ll nip over there for some cucumber sandwiches. Five thousand heavy paces and two hours later we are there. Half a minute to cross the Solar System and two hours to the nearest star, still we can do it on a Sunday morning and get back home for tea and biscuits.
The following weekend we are going to walk right across our Galaxy, The Milky Way. We do not get back home for tea because it takes twenty three years. Good job I took a drink.
We are now a familiar giant figure in space. The denizens of distant worlds, if such there are, remark, there he goes again, that huge bloke, wonder where he’s off to this time.
We are off to other Galaxies. Space is full of them. They are as far as we can see with telescopes or listen to with radios, if they have got Your Hundred Best Tunes going out.
There’s a nice close Galaxy over there. It’s just about the closest and is called Andromeda, I’ll walk over there, better not start off too quick, pace myself. Best foot forward. It takes me twenty five thousand years to walk to Andromeda.
We will finish our peregrinations by walking to the furthest Galaxy yet discovered. A complication is that Galaxies are walking away from us at a bit of a lick. As if I hadn’t got enough to do without playing catch-up. We shout at it, ‘Hoy, hold on.’ It stops and waits for us and we walk over. It takes us twenty five million years to get there.
Remember how big we are? Now do you understand the size of The Universe?
Written by my late father 35 years ago.
Got a minute? Good. Then you can understand the big picture, the Universe, once and for all, which is normally bloody difficult. The clever men from Oxford have been trying for ever and they wind up confusing us as comprehensively as the clever men from Cambridge. But I have it, we are going to run through it!
It’s easy, we don’t need any theories like Archie Medes making his bathroom floor wet or formulas from Einstein.
I will bring the Universe into easy comprehension for all, and it has never been done before. You see, IT ALL DEPENDS ON HOW BIG YOU ARE. To us humans, being too small you see, between five and six feet tall, (This is not an exact science, it doesn’t need to be.) the Universe is a vast gobblydegook of light years, and parsecs and red shifts. Only God, (If he made it) knows what it’s all about and how far it goes. Imagine now how big it would all seem to you if you were a cat, say one foot tall. Five to six times larger than it seems now, five to six times more passing the understanding, however clever a cat you were. Imagine now you are an ant, a microbe. It’s too much, it’s no go the anty-man, it’s no go Blavatsky.
Right, on we go. Microbes, ants, cats and people are all too small to understand the vastness of space so let us do a ‘thought experiment.’ No test tubes, no sparks on shiny balls, no hair all over our face. Einstein did them all the time and are we going to admit he would be any better at it than us. No.
How big is space? That’s our experiment.
Here we go. Put on your running shoes. The sun is one hundred million miles away from Earth. Near enough. If you want exact there are special books you can get, take a large bag to carry them.
WE BECOME HUGE GIANTS, now we can understand the vastness of space, at last. So we imagine we are two hundred million miles tall, and every long step we take is one hundred million miles long. It’s a familiar distance, we don’t do it every day but it’s roughly the distance from the Earth to the Sun. What a stride! What huge trousers. Now to start running around the Universe.
We step out from Earth, bonk, one step and we are on the Sun. Bit hot, let us trot off to the furthermost planet in our Solar System, namely Pluto. Forty steps, a half minute stroll, not so far as the paper shop, and we are standing, smiling broadly on the planet Pluto.
Fine view from here, lots of stars, all over the place, they are our gang. The Galaxy of which the Sun is a member. We are called collectively The Milky Way. There are none very close, bit off-putting, might be in for a bit of a long walk here. We spot the closest to us, it has a name plate, Alpha Centauri, sounds posh, we’ll nip over there for some cucumber sandwiches. Five thousand heavy paces and two hours later we are there. Half a minute to cross the Solar System and two hours to the nearest star, still we can do it on a Sunday morning and get back home for tea and biscuits.
The following weekend we are going to walk right across our Galaxy, The Milky Way. We do not get back home for tea because it takes twenty three years. Good job I took a drink.
We are now a familiar giant figure in space. The denizens of distant worlds, if such there are, remark, there he goes again, that huge bloke, wonder where he’s off to this time.
We are off to other Galaxies. Space is full of them. They are as far as we can see with telescopes or listen to with radios, if they have got Your Hundred Best Tunes going out.
There’s a nice close Galaxy over there. It’s just about the closest and is called Andromeda, I’ll walk over there, better not start off too quick, pace myself. Best foot forward. It takes me twenty five thousand years to walk to Andromeda.
We will finish our peregrinations by walking to the furthest Galaxy yet discovered. A complication is that Galaxies are walking away from us at a bit of a lick. As if I hadn’t got enough to do without playing catch-up. We shout at it, ‘Hoy, hold on.’ It stops and waits for us and we walk over. It takes us twenty five million years to get there.
Remember how big we are? Now do you understand the size of The Universe?
Written by my late father 35 years ago.
Watching too much YouTube one evening when wife was out babysitting.
Went down a few space videos starting with the usual well known experts. Soon ventured into less known stuff that was absolutely convincing and well made ,suggesting the universe was relatively small , and all the endless space stuff was nonsense.
Went down a few space videos starting with the usual well known experts. Soon ventured into less known stuff that was absolutely convincing and well made ,suggesting the universe was relatively small , and all the endless space stuff was nonsense.
I stumbled across this the other day, I think it works better on a phone/tablet but be prepared to do a lot of swiping!
https://www.joshworth.com/dev/pixelspace/pixelspac...
https://www.joshworth.com/dev/pixelspace/pixelspac...
Most of us don't even grasp the scale of our own solar system let alone the universe.
If I've got the timing link right, the next couple of minutes is a lovely little demo of the distance from the earth to the moon
https://youtu.be/7kCdY8o8cFI?si=MltHBv6UjMd3HuOM&a...
If I've got the timing link right, the next couple of minutes is a lovely little demo of the distance from the earth to the moon
https://youtu.be/7kCdY8o8cFI?si=MltHBv6UjMd3HuOM&a...
Zetec-S said:
I stumbled across this the other day, I think it works better on a phone/tablet but be prepared to do a lot of swiping!
https://www.joshworth.com/dev/pixelspace/pixelspac...
Damn, yeah that puts things into perspective pretty well.https://www.joshworth.com/dev/pixelspace/pixelspac...
Skodillac said:
Football pitches. Waleses. These are the only real measures of size.
You need the Registers online conversion calculatorhttps://www.theregister.com/Design/page/reg-standa...
welshjon81 said:
So, consider this.
The observable universe has a diameter of roughly 93 billion light-years and contains around 2 trillion galaxies.
How is the observable universe that big if it's only said to be 13.8 billion years old? I would have thought the observable bubble couldn't be larger than the age of it, otherwise it suggests that either it's much older than we're told or light travels faster than we think it does.The observable universe has a diameter of roughly 93 billion light-years and contains around 2 trillion galaxies.
thegreenhell said:
How is the observable universe that big if it's only said to be 13.8 billion years old? I would have thought the observable bubble couldn't be larger than the age of it, otherwise it suggests that either it's much older than we're told or light travels faster than we think it does.
The furthest away bits we can see emitted their light 13.8 billion years ago and it's only just reached is, in the mean time they've been travelling further away from us and are now around 46 billion lightyears away.I think.
thegreenhell said:
welshjon81 said:
So, consider this.
The observable universe has a diameter of roughly 93 billion light-years and contains around 2 trillion galaxies.
How is the observable universe that big if it's only said to be 13.8 billion years old? I would have thought the observable bubble couldn't be larger than the age of it, otherwise it suggests that either it's much older than we're told or light travels faster than we think it does.The observable universe has a diameter of roughly 93 billion light-years and contains around 2 trillion galaxies.
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