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Up arrowOptical illusion

Answer

  

Fraser spiral

Can you get to the centre?

Start at the red dot and try to follow the spiral to the centre. Where do you end up?

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At a glance, this looks like a white spiral on a black background. The sides of the spiral have triangular prongs slicking out, both inwards and outwards, at frequent intervals. These triangular prongs, or spikes, are smaller and appear more densely spaced along the spiral at it moves towards its centre, which is a round black circle. And this is the clue – this is not a spiral at all, but a collection of concentric circles, made up of very short curved segments that overlap. As the segments that make up the circles appear to tilt more than they actually do, this gives the illusion that one is looking at a spiral that disappearing into a the distance.

For a description of the image place your cursor over it (certain browsers only), or click here for an audio transcript.

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