Early Morning
So I forgot to blog before I went to work! And it's well after midnight now...
Work was pretty cool tonight. I think it's just because it was dead and I was working with cool people on floor. And everything ran smoothly.
I've got nothing to post about so I'm going to talk about stars. I noticed the stars on the way home. The summer night sky brings back good memories from when I was a kid - late nights out on the beach at Piha and stuff, lying flat on our backs admiring the stars and looking for meteors and just perfectly happy.
At this time of night at this time of year those same stars are in the eastern sky. All the old favourites. I was going to go outside and look at them for a while but I can't be bothered. It's too late in the morning.
I love just taking half an hour to look at the stars. Apart from being incredibly restful, it's really awe-inspiring. There's an entire universe out there that exists apart from us - and if something happened to us like civilisation collapsed or humanity was wiped out or the earth was pulverised, the the rest of the universe wouldn't even notice.
The sheer size of what's out there is absolutely mind-boggling! If you were to make a model where the Earth was slightly smaller than your thumbnail, it would be situated roughly a hundred metres away from the sun, which would be the size of a large beachball, at about 80cm in diameter. The nearest star from us, Proxima Centauri, would be a smaller ball - maybe about the size of a soccer ball, and you would have to place it about three quarters of the way around the world from the "sun". So if you were to place the Earth and sun in Auckland, New Zealand, you would have to travel east through the South Pacific Ocean, across Chile and Argentina, through the Southern Atlantic Ocean, passing south of South Africa, and about halfway across the southern Indian Ocean to reach your soccer ball - the nearest star to the sun.
And that's the nearest star! Most of the stars you can see in the night sky are tens or hundreds of times further away again! And then when you look through binoculars you can see thousands of thousands more stars that are so far away they can't be seen with the naked eye. Some of those stars are incredibly bright - thousands of times brighter than the sun - yet they're so unimaginably far away that they can only be seen as a faint, barely visible, point of light.
And these are only the closest stars to us. When you look at the Milky Way - the hazy white band of light that stretches across the sky, you are looking at billions upon billions of stars that are so far away that we can't even see them as points of light - they're so far away that even our most poweful telescopes can't tell one star from another - they just appear as one big haze ... and yet these stars aren't even remotely close to each other - from one of those stars that make up the hazy band of light we see, all the other stars around it would appear as faint points of light that are incredibly far away from it - yet they're so much further from us that from our point of view they seem to be essentially in the same place!
There are countless hundreds of billions of worlds in our galaxy, all separated by unimaginable distances. The centre of our galaxy can be seen in the winter night sky. When you look at it (all you can see is the haze of light made up from billions of widely separated stars that are so far away from us that we can't tell them apart) - you are looking across approximately 24,000 light years of space! That's right - the centre of our galaxy is SO far away that it takes light 24,000 years to reach us from it! By comparison, Archaeologists tell us that the first civilisation emerged only about 6,000 years ago, and the Ice Age ended about 10,000 years ago!
Or to quote Wikipedia, the main disk of the galaxy is about 80,000 to 100,000 light-years in diameter, about 250,000 to 300,000 light-years in circumference, and outside the Galactic core, about 2,300–2,600 light-years in thickness. The galaxy is estimated to contain 200 billion stars but this number may be as high as 400 billion if small-mass stars predominate. As a guide to the relative physical scale of the Milky Way, if the galaxy were reduced to 130 km (80 mi) in diameter, the solar system would be a mere 2 mm (0.08 inches) in width.
That's right, when you copy and paste in Firefox, it even copies the formatting. And no, it doesn't let you change it.
And it doesn't end there. If you go out of the city to a dark spot, and especially if you take binoculars, you can see thousands upon thousands of other galaxies in the sky. They reckon there might be as many as 80,000,000,000 galaxies in the observable universe. The human mind can't even comprehend a number that big! That's 80 billion galaxies, all home to so many billions of stars so incredibly far away from each other that they can only see most the other stars in the galaxy as a collective haze! Then each galaxy is so far away from the next that many of them can only be seen as small blobs or points of light themselves!
And it just keeps getting bigger. Galaxies group together in clusters. Many of the galaxies in a cluster are so far away from each other that they can only be resolved by the most powerful telescopes. These clusters are merely clumps in even bigger groups called superclusters. Superclusters are joined together by streams of galaxies called "filaments". Between the filaments of galaxies that join the superclusters are unimaginably immense gaps called voids, where there is nothing. No galaxies, and therefore no stars. If you were in the middle of one of these voids it would just be pure black. The nearest galaxies would be so far away that you wouldn't be able to see them without an extremely powerful telescope. There would be no light at all.
And this isn't just some story. You can step out of your back door on a fine night and see it for yourself. This is your universe .... this is where you live. And it is utterly incredible!
Work was pretty cool tonight. I think it's just because it was dead and I was working with cool people on floor. And everything ran smoothly.
I've got nothing to post about so I'm going to talk about stars. I noticed the stars on the way home. The summer night sky brings back good memories from when I was a kid - late nights out on the beach at Piha and stuff, lying flat on our backs admiring the stars and looking for meteors and just perfectly happy.
At this time of night at this time of year those same stars are in the eastern sky. All the old favourites. I was going to go outside and look at them for a while but I can't be bothered. It's too late in the morning.
I love just taking half an hour to look at the stars. Apart from being incredibly restful, it's really awe-inspiring. There's an entire universe out there that exists apart from us - and if something happened to us like civilisation collapsed or humanity was wiped out or the earth was pulverised, the the rest of the universe wouldn't even notice.
The sheer size of what's out there is absolutely mind-boggling! If you were to make a model where the Earth was slightly smaller than your thumbnail, it would be situated roughly a hundred metres away from the sun, which would be the size of a large beachball, at about 80cm in diameter. The nearest star from us, Proxima Centauri, would be a smaller ball - maybe about the size of a soccer ball, and you would have to place it about three quarters of the way around the world from the "sun". So if you were to place the Earth and sun in Auckland, New Zealand, you would have to travel east through the South Pacific Ocean, across Chile and Argentina, through the Southern Atlantic Ocean, passing south of South Africa, and about halfway across the southern Indian Ocean to reach your soccer ball - the nearest star to the sun.
And that's the nearest star! Most of the stars you can see in the night sky are tens or hundreds of times further away again! And then when you look through binoculars you can see thousands of thousands more stars that are so far away they can't be seen with the naked eye. Some of those stars are incredibly bright - thousands of times brighter than the sun - yet they're so unimaginably far away that they can only be seen as a faint, barely visible, point of light.
And these are only the closest stars to us. When you look at the Milky Way - the hazy white band of light that stretches across the sky, you are looking at billions upon billions of stars that are so far away that we can't even see them as points of light - they're so far away that even our most poweful telescopes can't tell one star from another - they just appear as one big haze ... and yet these stars aren't even remotely close to each other - from one of those stars that make up the hazy band of light we see, all the other stars around it would appear as faint points of light that are incredibly far away from it - yet they're so much further from us that from our point of view they seem to be essentially in the same place!
There are countless hundreds of billions of worlds in our galaxy, all separated by unimaginable distances. The centre of our galaxy can be seen in the winter night sky. When you look at it (all you can see is the haze of light made up from billions of widely separated stars that are so far away from us that we can't tell them apart) - you are looking across approximately 24,000 light years of space! That's right - the centre of our galaxy is SO far away that it takes light 24,000 years to reach us from it! By comparison, Archaeologists tell us that the first civilisation emerged only about 6,000 years ago, and the Ice Age ended about 10,000 years ago!
Or to quote Wikipedia, the main disk of the galaxy is about 80,000 to 100,000 light-years in diameter, about 250,000 to 300,000 light-years in circumference, and outside the Galactic core, about 2,300–2,600 light-years in thickness. The galaxy is estimated to contain 200 billion stars but this number may be as high as 400 billion if small-mass stars predominate. As a guide to the relative physical scale of the Milky Way, if the galaxy were reduced to 130 km (80 mi) in diameter, the solar system would be a mere 2 mm (0.08 inches) in width.
That's right, when you copy and paste in Firefox, it even copies the formatting. And no, it doesn't let you change it.
And it doesn't end there. If you go out of the city to a dark spot, and especially if you take binoculars, you can see thousands upon thousands of other galaxies in the sky. They reckon there might be as many as 80,000,000,000 galaxies in the observable universe. The human mind can't even comprehend a number that big! That's 80 billion galaxies, all home to so many billions of stars so incredibly far away from each other that they can only see most the other stars in the galaxy as a collective haze! Then each galaxy is so far away from the next that many of them can only be seen as small blobs or points of light themselves!
And it just keeps getting bigger. Galaxies group together in clusters. Many of the galaxies in a cluster are so far away from each other that they can only be resolved by the most powerful telescopes. These clusters are merely clumps in even bigger groups called superclusters. Superclusters are joined together by streams of galaxies called "filaments". Between the filaments of galaxies that join the superclusters are unimaginably immense gaps called voids, where there is nothing. No galaxies, and therefore no stars. If you were in the middle of one of these voids it would just be pure black. The nearest galaxies would be so far away that you wouldn't be able to see them without an extremely powerful telescope. There would be no light at all.
And this isn't just some story. You can step out of your back door on a fine night and see it for yourself. This is your universe .... this is where you live. And it is utterly incredible!
posted by David | 2:36 am
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