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No matter which stars or on show or which teams are competing, one thing will stay constant at this year's World Cup - the ball.

Unveiled by adidas a few months ago, the so-called 'Brazuca' is the official ball of Brazil 2014 and it's the 12th ball adidas have made for the World Cup.

And now the science inside the ball has been revealed to show how the best players in the world will have the best technology in the world on the pitch.

The science behind adidas's football for this World Cup has been revealed. The ball is known as the 'Brazuca' (pictured) and it is apparently a big improvement from the last World Cup. It has longer and deeper seems to make it less volatile in the end that mean it will travel further and more accurately during games

Adidas came under fire at the 2010 World Cup in South Africa as the ball used at that tournament, the Jabulani, was criticised for its unpredictability.

The sports giant claims the Brazuca, though, will have vastly improved touch and accuracy.'We do extensive flight path analysis and the results have shown constant and predictable paths with deviations hardly recognisable,' Matthias Mecking, Adidas football director, told the BBC.

The ball itself weighs 437 grams (0.96 pounds) and it has a water absorption rate of just 0.2%, meaning it can retain its shape, size and weight even in the rain.

It is created by six propeller-shaped polyurethane panels being themally bonded together.

Between the seams the Brazuca also has a different geometry to different balls, helping it remain more stable in the air.'The most important thing on the soccer ball is how much roughness you have,'

Dr Rabi Mehta, an aerodynamics expert at Nasa's Ames Research Center in California, told the BBC.
Smoother balls, as seen with the previous Jabulani, are more unpredictable due to a process known as 'knuckling'.

As air passes over the seams it can create a force that knocks or moves the ball.

The Brazuca, with its multiple seams and roughness, will be less prone to the 'volatile swoops' of the Jabulani.

'The smoother you make the ball, the higher the speed at which it knuckles,' says Dr Mehta.

'In essence what happened in my opinion is that with the traditional ball, the critical speed at which you got maximum knuckling was lower than the typical kicking speed in World Cup soccer.

'By making the ball smoother, that critical speed went up and happened to coincide with the typical kicking speeds, about 50 to 55 miles (80 to 88 kilometres) per hour, especially in free kick situations.'

This year's rougher ball brings us 'back to square one' says Dr Mehta.

The Brazuca is set to be one of the most aerodynamic balls used at a World Cup in recent memory. Its deep and logn seems, seen here, ensure that it won't move unpredictable in the air

Another way the Brazuca has been improved over the Jabulani from four years ago is the depth of the seams.

The Brazuca's are about 0.06 inches (1.56 millimetres), compared to just 0.02 inches (0.48 millimetres) for the Jabulani, about three times shallower.

The total length of the seams on the Brazuca are also longer, at 128.7 inches (327 centimetres) compared to 79.92 inches (203 centimetres) on the Jabulani

All of this combines to make the ball rougher, and it also travels further – like dimples on a golf ball, the seams disrupt the flow of air.

'This agitation is essential for fast and reliable flight,' Dr Simon Choppin, a research fellow at the Centre for Sports Engineering Research at Sheffield Hallam University.

'A perfectly smooth ball experiences large amounts of drag and high aerodynamic forces.

'The seams of a football disturb the flow of the air.

'This results in a smaller wake-area of low pressure - behind the ball - reducing the pressure difference and reducing the force, which slows the ball down. The lower drag force means the ball travels for a longer distance.'

The result is that the ball should more closely resemble traditional 32-panelled balls that most footballers are used to.

Despite this ball having just six panels, the deep and long seams will create one of the most advanced footballs yet used at a World Cup.

'I am pretty sure the Brazuca is going to behave more like the traditional 32-panel internally stitched ball, so the complaints we got in the last two World Cups will be minimised,' says Mehta.