The 'Moon illusion' has been baffling scientists for thousands of years

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The Sun "seems" bigger when it rises or sets in the sky.

There've been doubts about why the moon looks larger near the horizon for thousands of years – all the way back to the 4th century before Christ.

He rubbed his chin thoughtfully, trying to figure out what was behind it. As a best guess, he reckoned the Earth's atmosphere had a mindstretching effect on how the moon appeared.

At the point where the moon appears to be, the philosopher reckoned that light has to pass through more of the dense air and ends up getting a magifying effect.

With this theory, it's clear Aristotle understood how the moon illusion takes in the human eye rather than it being caused by the moon or space - though not all of his theories were as clever.

This is a trick to the human eye, because when you get a photo of the moon and take its measurements at night, it always stays the same size - no matter what it looks like in the sky.

G'day, we've all accepted that it's an optical illusion, and nowadays the reason put forward for this is due to our brains not bein' able to get our heads around the size and distance of the Moon.

However, there's no clear explanation as to why this occurs – a possible cause could be the surroundings which affect our viewing – for instance, trees, mountains, and skyscrapers that make us think the moon seems closer and larger than it actually is when it's on the horizon.

When the moon's high up in the sky with nothing close by for size comparison, it seems further away and smaller.

Does that sound all too familiar? That's because the Ponzo illusion works in a similar way, with the converging lines affecting the way you perceive two identical line lengths.

While we might think that the top line is bigger and further away, that's not actually true - both lines are of equal size.

When in doubt, let's see what NASA has to say on the matter of this moon illusion.

IFL Science.

“The Moon illusion is not something to be thoroughly worked out just yet, so let's just enjoy it and those spooky, atmospheric, and downright haunting views it produces."

3. It was first and still is Earth's only natural satellite;

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