The Scale of Things...
So how big is "Space" and just how far is far?
Find out here....

Fact 1/ Space is really really big, in fact you have no idea just how mind bogglingly huge it is,.... you might think it's a long way down to the shops to buy some milk but that's just peanuts to space......
Thanks to the late Douglas Adams for that one.

If you visited every beach in every country and tried to name every grain of sand after every star in the known universe, you wouldn't have enough sand!

We live in a modestly huge galaxy called the Milky Way... this our home galaxy, contains about 200 billion stars of which, our star, Sol or the Sun, only a small and humble little star... If you go out on a clear night and look up in summer you will see a very very bright star Sirius. This star is 100 times the mass of our Sun and burns very fast, hot and white. The good thing for us is that when a star is small and stable, it will burn steadily for billions of years. This gives us a nice long existence as an evolving planet. Sirius may only last a couple of billion years or even less before using all it's fuel and ending in the most violent event in the known universe.... a Super Nova explosion... the left over, will be compressed into a Black hole!

Around the Sun we have the planets.  All are different sizes, some are tiny compared to their bigger brothers. The Earth, could fit inside Jupiter 300 times!

Now, if you ever wondered how to visualize the sizes of the planets and distances involved in their orbits. try the table at right. For our model of the planets in our scaled down Solar system we are using a Net ball (241.3mm / 9.5 inch diameter ball) to represent the Sun.

(In reality the Sun is 1,391,900 kilometres in diameter and Earth is only 12,742 kilometres in diameter)

The dimensions given below are based on... If the Sun being the size of a Net ball, then.....

Body Name Bodies scaled diameter in mm Bodies scaled orbit radius in meters
The Sun 241.3 (about the size of a Net ball) N/A
Mercury 0.8 mm in diameter 10.046 meters away
Venus 2 mm in diameter 18.741 meters away
The Earth 2.2 mm in diameter 25.929 meters away
Mars 1.1 mm in diameter 39.498 meters away
Jupiter 24.1 mm in Diameter 134.898 meters away
Saturn 20.1 mm in diameter 247.384 meters away
Uranus 8.1 mm in diameter 497.595 meters away
Neptune 7.8 mm in diameter 780.103 meters away
Pluto (a Dwarf planet) 0.3 mm (scales to a grain of salt!) Just over a kilometre away

At this scale the speed of light (about 300,000 kilometres per second)
would be 52 mm per second. So, travelling at the speed of light, it takes 8 minutes for light from the sun to reach us...

To get to the nearest stars, Alpha Centauri, will take you 4.5 years! at the speed of light... It is 4,030,000,000,000,000 Kilometres away!!! on this scale that's 7003.1 kilometres.... At 52 millimeters per second, it take a while to go 7000 kilometres....
If that's not exhausting enough, then head for the centre of the Milky Way, it's 45,446,538 kilometres away if the sun where the size of a Net ball...
Of course there are millions and millions of similar galaxies like the milky way, spread out across the universe all at mind boggling distances.... the further out we look the more we find....

SPACE IS BIG...Got the idea?

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