The size of Stars

Author
Discussion

nick heppinstall

Original Poster:

8,081 posts

281 months

Friday 6th September 2013
quotequote all
Check out this short video. Just amazing.

http://www.youtube.com/watch?v=g4iD-9GSW-0

TwigtheWonderkid

43,425 posts

151 months

Saturday 7th September 2013
quotequote all
That's big.

RobGT81

5,229 posts

187 months

Thursday 12th September 2013
quotequote all
This is quite cool, gives you an idea of the size of big stuff.

http://htwins.net/scale2/

nick heppinstall

Original Poster:

8,081 posts

281 months

Thursday 12th September 2013
quotequote all
RobGT81 said:
This is quite cool, gives you an idea of the size of big stuff.

http://htwins.net/scale2/
Yeah that's cool !

NadiR

1,071 posts

148 months

Saturday 14th September 2013
quotequote all
RobGT81 said:
This is quite cool, gives you an idea of the size of big stuff.

http://htwins.net/scale2/
Thanks for sharing, that was very cool indeed.

TheTurbonator

2,792 posts

152 months

Saturday 21st September 2013
quotequote all
Another poster posted this a while back, kept it as I find it fascinating.


peterperkins

3,152 posts

243 months

Friday 25th October 2013
quotequote all
Running Through Space.

Or….. The Universe in Perspective.

Got a minute? Good. Then you can understand the big picture, the Universe, Stars etc 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 and the size of things 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 the distance 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 next star, still we can do it on a Sunday morning and get back home for tea.

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?

vescaegg

25,583 posts

168 months

Friday 25th October 2013
quotequote all
peterperkins said:
Running Through Space.

Or….. The Universe in Perspective.

Got a minute? Good. Then you can understand the big picture, the Universe, Stars etc 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 and the size of things 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 the distance 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 next star, still we can do it on a Sunday morning and get back home for tea.

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?
Love that.

But..

wobblewobblewobblewobblewobble

Gnits

920 posts

202 months

Friday 25th October 2013
quotequote all
That is good - massive sense of awe when you can get a rough grasp on some of this stuff!

Regarding VY Canis Majoris I heard a lovely explanation:

If the Earth was 1cm across then our Sun would be about 1m20cm across and be about 117m away from us.


On this same scale VY Canis Majoris would be 26Km across.

CommanderJameson

22,096 posts

227 months

Monday 28th October 2013
quotequote all
Gnits said:
That is good - massive sense of awe when you can get a rough grasp on some of this stuff!

Regarding VY Canis Majoris I heard a lovely explanation:

If the Earth was 1cm across then our Sun would be about 1m20cm across and be about 117m away from us.


On this same scale VY Canis Majoris would be 26Km across.
Intriguingly, VY Canis Majoris is also very much less dense than our Sun.

Wikipedia said:
VY Canis Majoris also illustrates the conceptual problem of defining the "surface" (and radius) of very large stars. With an average density of 0.000005 to 0.000010 kg/m3, the star is a thousand times less dense than the atmosphere of the Earth (air) at sea level. It is also undergoing strong mass loss with the outer layers of the star no longer gravitationally bound.

MiseryStreak

2,929 posts

208 months

Monday 28th October 2013
quotequote all
peterperkins said:
Running Through Space.

...

Now do you understand the size of The Universe?
I liked that. But the giant has broken relativity by moving at approx 1 au/sec which is 499 times the speed of light. In fact he would have to think very hard about moving at all without causing a physics meltdown. His blood would be flowing backwards in time for a start. Even by having the thought about not having a thought his neurons would have fired electrical impulses to arrive at a time before his brain was even there.

I guess this is why you shouldn't stretch an analogy you end up with a giant headfk.