This We Know : Spaceship Earth
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By Tom Evans
It’s estimated that our brains contain 80 billion neurons. This is about the same as the number of stars in a medium sized galaxy. This may not be a coincidence.
Our Home moves at about 66,000 miles an hour around its parent star. This means all the inhabitants travel about half a billion miles a year on their Spaceship Earth.
The Sun itself is moving around 500,000 miles an hour around the centre of the galaxy.
The Earth is just over 24,000 miles in circumference at the equator. It revolves on its axis in what 7 billion life forms refer to as being 24 hours. This means the ground under your feet is moving at over 1000 miles an hour, unless you are near one of the Poles.
We are in constant motion. Yet, for many, life stands still. For some it even goes backwards.
Spaceship Earth weighs in at around 5.972 sextillion tonnes. A sextillion is 1,000,000,000,000,000,000. That’s a lot of noughts! A million billion indeed.
Of that, around 0.02% is water and 97.5% of the water is in the oceans. The air we breathe is just a millionth of the weight of the Earth.
All life forms on the planet weigh in at between 1000 to 2000 billion tonnes (there is some debate over the exact number). Of that humanity clocks in at 100 million tonnes.
Those one billion or so overweight people are doing their best to change these statistics. Those that are malnourished are balancing things out.
When we compare our weight to the air and water that keeps us alive, we are insignificant. We are almost weightless.
Our brains weigh in at around 2 to 3 kilograms. So if you add the weight of all our brains together, they are an even more minuscule amount of matter in the bigger scheme of things. Yet we take them so seriously.
Yet what makes our brain so remarkable though is that it seems to have gained the ability to be self aware and to ask questions about how it came to be.
Note in passing that all other brains for all other life forms are no less remarkable. Self awareness too is not restricted to humans. Species such as chimpanzees, magpies and dolphins can all recognise themselves in a mirror.
As we can see as children grow up, self awareness increases in waves and steps. Every seven years or so, a new version of Us arrives.
What we never know in one state is what the higher state of awareness will bring. We also do not know the upper limit of our capabilities. •
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This inspiring article is serialized from the ebook This We Know © 2012 Tom Evans. All rights reserved. More »