SSS 2010-06-29

（单词翻译）

This is Scientific American’s 60-Second Science. I’m Karen Hopkin. This will just take a minute.

Those of you following the World Cup know that at this stage there can be no more draws. Ties are broken during overtime¹ play, or in a penalty kick shootout in which a goalkeeper’s ability to anticipate the ball’s flight can mean the difference between victory and elimination². Now, scientists at Rensselaer Polytechnic³ Institute have discovered how a kicker’s body can betray whether he’s aiming left or right.

In a penalty shot, it’s kicker versus⁴ goalkeeper. And with the shooter standing⁵ just 12 yards from the goal, that ball can touch net in about half a second. That’s faster than a keeper can launch himself from the goal’s center to either post. Which means that a goalkeeper has to start moving before the kicker’s foot meets the ball. And he has to guess correctly which way to dive.

To figure out how good goalies might up their odds⁶, scientists attached motion detectors⁷ to college-level penalty kickers. And they found a handful of indicators⁸ that reliably predict kick direction, such as the angle of the kicker’s hips⁹ and how he plants his supporting foot.

Good goalies may be able to read those subtle cues. Meaning that they use their hands, and their heads.

Thanks for the minute for Scientific American’s 60-Second Science. I’m Karen Hopkin.