Over the last few evenings the earth has been taking a bit of a battering. Seen by some but missed by many our planet has been slowly spinning through a stream of debris left by a giant comet that has been circling the sun since the birth of the solar system. Think about that for a minute…since the birth of the solar system!
The comet, known as Swift-Tuttle, is a 27-kilometre-wide iceberg hurtling through space. It spends most of its time in the outer solar system, reaching beyond the orbit of Pluto. Then, every 133 years, it dives past the sun, replenishing the supply of Perseids or meteors.
Swift-Tuttle, like all the comets, is in a constant state of disintegration. Slowly coming apart as it continues on its mammoth journey. Comets hail from the outer solar system where icy compounds are easily maintained because it is so cold. As a comet approaches the sun, however, the heat melts the ice and solid grains of dust are released into space. This creates the ephemeral tails that are seen stretching across the night sky.
As the tails disperse they create the debris streams that give us meteor showers.
Every Perseid you see was once in the tail of this comet and each tiny fragment that hits our atmosphere is usually no larger than a speck of dust. Yet it burns up with an incandescent display that we call a meteor – a shooting star.
When these tiny fragments slice into the upper atmosphere of our planet they are travelling faster than 160,000 kilometres per hour (100,000 miles per hour). This speed compresses the air in front of them and as it is squeezed, like any gas, it heats up and in this case the temperatures reach several thousand degrees resulting in the meteor burning up.
As you’re looking at these pictures or as you were watching it happen consider this: Every single one of those meteors was born as the earth was forming, about 4.5 billion years ago and has been hurtling through space ever since. Imagine if you could actually ‘catch‘ one of these meteors, one of these ‘falling stars‘ before it burned up. The story it would have to tell would help us to understand further the very birth of our solar system.
Very cool!
A waxing moon rises over the Yorkshire Moors with Venus (below left of the moon) and Jupiter (upper right of the moon) visible
With a waxing moon hidden by clouds and the brightest planet in this picture, Jupiter, visible and the constellation ‘Pleiades’ in the upper right corner a meteor
streaks across the evening sky over the Yorkshire Moors
A Perseid meteor streaks across the night sky
A Perseid meteor reaches the end of its journey above New Ralph’s Cross on the Yorkshire Moors
A Perseid meteor is seen streaking across the sky with the constellation Pleiades also known as ‘Seven Sisters’ visible at lower right
New Ralph’s Cross is silhouetted against heavy mist but a waxing moon and Jupiter shine through
A Perseid meteor burns up as it enters the atmosphere with Jupiter shining brightly in the skies above the Yorkshire Moors
In the skies above New Ralph’s Cross on the Yorkshire Moors four Perseid meteors streak across the sky
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