Sunday 20 July 2014

Our Place In The Universe

In celebration of the momentous occasion of Neil Armstrong stepping out onto the Moon 45 years ago today, June 20th has been deemed Space Exploration Day and events are going on all around the country to show just what an amazing feat this was and what an amazing place the Universe is.
It is hard to grasp just how impossibly immense the Universe is but an important step is to realise just how big a light year is. The Sun is approximately 93 million miles away and it takes 8 and a half minutes for the light to reach the earth from our star which means that if light can travel 93 million miles in 8 and a half minutes, in a year light will travel 5.88 trillion miles, so if something is a light year away, its 5.88 trillion miles.  
With that firmly in your mind, try to imagine our Milky Way being 100 light years across but the largest galaxy we have discovered is IC 1101 which is 120,000 light-years wide.
Our Sun may be impressive to us but in Universal terms it is a very ordinary, medium sized star 864,938 miles in diameter. It's surface temperature is 10 kilokelvins which when you consider the heat it generates on us 93 million miles away is impressive, until you consider the romantically named HD62166 which measures a scorching 200,000 kilokelvins or the Epsilon Orionis, the middle star of Orion's Belt which burns 400,000 times brighter than the Sun.
With a diameter of 3 billion, a star called VY Canis Majoris has an estimated diameter of 1,700,000,000 billion miles which would swallow our sun 8 billion times over.
The Earth is 7,901 miles diameter (you could fit 1.3 million Earths inside the Sun) and makes us the 3rd largest planet in our solar system with Jupiter the largest at 86,881 miles which is huge but not as large as the largest planet we have discovered, WASP-17b which is twice the size of Jupiter or 636 times larger than the Earth.
The Earth rotates at 460 meters per second or 1,000 miles per hour but even that is peanuts compared to what space can serve up. VFTS 102 is the fastest spinning star we’ve ever found, and its surface goes upwards of 440,000 meters per second or 1 million miles per hour.
When the Apollo 11 rocket launched from the surface of the Earth, it needed to reach a speed of at least 25,000 mph to escape the earths gravitational pull and the maximum speed we have achieved is 35,000 mph which is fast but almost half the speed of the Sutter’s Mill meteorite which blazed through the sky in 2012 at 64,000 mph, almost twice as fast as we’ve ever shot a rocket.
The Universe really is an amazing and beautiful thing but compared to what the Universe offers, we really are just a small, insignificant ball of rock in a solar system tucked away on the arm of a galaxy that is one of hundreds of billions in an unfeasibly vast universe.

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