The Sun is just one of hundreds of billions of stars in our galaxy.
In a way, there’s nothing very special about it.
It’s a fairly ordinary star -
not particularly large or bright by stellar standards.
But it’s very special to us.
The Sun makes life on Earth possible.
Cultures across the world, and throughout the ages,
worshipped the sun.
In some ways, modern life has cut us off from the Sun.
In the developed world we spend 90% of our time indoors –
and yet the Sun is still a powerful force underpinning our lives.
The Sun affects our perception of beauty.
When people talk of the “golden hour”,
that time just before the Sun sets, it’s a real thing.
The Sun isn’t actually yellow or orange or even red.
It’s all the colours mixed together.
When the Sun rises or sets in the sky, the shortwave colours -
green, blue and violet -
are scattered,
leaving only the yellow and the red part of the spectrum,
giving that amazing glow.
When the Sun is high in the sky, its blue waves bounce around –
which is why the sky looks blue.
And when you see a rainbow,
that’s the light from the sun separated
into all its magnificent colours.
Although we talk of the Sun rising in the east and setting in the west,
that’s not quite true.
It just seems that way to us.
The Sun stays in the same place.
It’s the Earth that rotates on its axis.
This movement of the Sun is deeply embedded in our biology.
When sunlight enters the eye,
it sends signals to a master clock in our brain
called the suprachiasmatic nucleus.
This internal clock regulates everything,
from when we sleep to how we digest a meal.
Messing with this finely-tuned machine,
when we work night shifts or fly across the world,
can make us feel pretty rough.
Even the bluish light from a mobile phone late at night
is enough to disrupt and confuse our internal body clock.
Being out of step with the Sun affects our mood
and our ability to think clearly.
And there’s evidence
that this kind of disruption can lead to higher rates of obesity,
heart disease, diabetes and even cancer.
We’re living out of step with the Sun
and some scientists say this could be causing a public health crisis.
When the sun is shining,
studies have shown that we tip more generously
and are more likely to splash out on luxury goods.
And crime may go down too.
One study in the US
found that when the clocks go forward for Daylight Savings Time,
the number of robberies, rapes and murders went down around 50%.
The Sun is a hell of a force to be reckoned with.
Every hour,
enough sunlight falls on the earth to power the world for a year.
Deep in its core, at around 15 million degrees Celsius,
the Sun is constantly fusing hydrogen together to make helium.
These nuclear reactions release vast amounts of energy
in the form of sunlight.
If only we could work out how to harness this.
But we are getting there.
It’s estimated that by 2022,
30% of our energy could come from renewables,
with solar growing faster than anything else.
The Sun is vast, dynamic…
and sometimes violent.
Viewed up close, the Sun’s surface looks like a raging sea of fire,
with huge eruptions
rising hundreds of thousands of kilometres into space.
There are even earthquakes on the Sun – called sunquakes.
And what happens on the Sun can impact us.
The Sun sporadically blasts huge clouds of charged particles
towards the Earth,
potentially wreaking havoc on the technology that we all rely on.
But 97% of people have never heard of solar storms.
In 1859, a gigantic solar storm hit the Earth,
creating auroras that covered the entire planet,
knocking out the telegraph network
and sending sparks flying from electrical equipment.
The solar storm of 1859 is still the largest on record.
But if a similar storm were to hit the Earth today,
the consequences for our way of life could be devastating,
knocking out electricity grids,
satellite navigation and communications
for days, weeks…
or even months.
No wonder people used to worship the sun.