NASA Boots the Jabulani [The Daily Telegraph]

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It’s the ball’s fault.

That’s the conclusion several British newspapers and at least one Latin American newspaper are helping their readers draw during the final week of World Cup action.

And this time they’ve got science on their side. NASA scientists at the Fluid Mechanics Laboratory at NASA Ames Research Center in Mountain View, Calif., concluded that the Jabulani — the official ball of the 2010 FIFA World Cup — tends to “knuckle under” or go wobbly at speeds of 45-50 miles per hour. 

A half-dozen articles published following the Netherlands’ July 6 trouncing of Uruguay to advance to the first all-European World Cup final in 32 years are citing this NASA research under headlines such as the Mirror‘s “NASA Joins Critics of Jabulani.”

As the British soccer blog the Spoiler put it in a July 7 post:

“Today’s news suggests that when NASA eggheads aren’t building rockets, or figuring out how best to consume a glass of orange squash when you’re floating, they’re chuckling knowingly to themselves, and patronising people who invent footballs.

“In a successful attempt to put some scientific weight behind something that most people had already noticed, NASA have confirmed that the new Adidas Jabulani World Cup football is, in fact, totally rubbish.”

NASA, of course, didn’t call the ball “totally rubbish”, but it did say this back in a June 18 press release:

“‘It’s quite obvious. You’re seeing a knuckle-ball effect,’ said Rabi Mehta, an aerospace engineer at NASA Ames. Mehta explained that when a relatively smooth ball with seams flies through the air without much spin, the air close to the surface is affected by the seams, producing an asymmetric flow. This asymmetry creates side forces that can suddenly push the ball in one direction and cause volatile swerves and swoops.

“From his research on tennis and cricket balls in wind tunnels, Mehta believes that the Jabulani ball will tend to knuckle at 45 to 50 mph, which coincides with the speed of the ball during free-kick around the goal area. Another point made by Mehta, is that a lot of the stadiums for the World Cup are located at high altitude (Johannesburg is at 5,500 feet) and this will affect the ball aerodynamics as well, since the air density is lower. At this high altitude, the ball will tend to fly faster (less drag) and swerve less (less lift).”

Perhaps it’s time to dispatch NASA Administrator Charles Bolden to England to help them feel better about their soccer accomplishments?