In living rooms and on Internet sites across the country Sunday night, there was only one sporting question that mattered: How did Odell Beckham Jr. make that catch?
By the next morning, in the laboratories and offices of physicists, mechanical engineers and sport scientists, the answer was being deduced through scrutiny of gyroscopic effects, vectors, linear and angular momentum, a coefficient of friction, mass, velocity and the material composition of the specialized glove on Beckham's hand.
In the end, there was a definitive conclusion: great piece of human athletic performance. At some point, even scientists put down the calculators and bow.
'It was a bit like Spider-Man,' said Jim Gates, a professor of physics at the University of Maryland. 'A near superhuman activity.'
But with the help of slow-motion video and other systematic and painstaking measurements, the roughly one second of Beckham's stunning acrobatics can be explained in exacting, technical detail.
The numbers still add up to Beckham doing something extraordinary.
The analysis starts with Eli Manning 's throw, which came from the Giants' 48-yard line. Manning let go of the football just to the left of the right hash mark. John Eric Goff, a professor of physics at Lynchburg College in Virginia and the author of 'Gold Medal Physics: The Science of Sports,' carefully assessed the video of Beckham's catch and determined that Manning's pass had traveled about 55 yards of horizontal distance on its way to Beckham's right hand.
The ball ascended on its path down the field until it was 10 yards higher than Manning's hand, and it left Manning's hand at about 56 miles per hour. By the time it arrived at the point where Beckham was jostling with Dallas cornerback Brandon Carr, the football was speeding along at about 46 miles an hour.
Measuring the trajectory and route of the football, Goff concluded that the pass had been heading out of bounds.
'Beckham had to bring the football to a complete stop - bringing its linear momentum to arrest - in 0.2 seconds,' Goff said. 'And that's not much time.'
But first, Beckham had to get in position as he was being shoved, grabbed and interfered with by Carr (two officials threw penalty flags).
'The visual acuity, the concentration, the body awareness and the strength to get his arm and shoulder oriented behind him and aligned with the ball - that's all amazing,' said Tony Schmitz, a professor of mechanical engineering and engineering science at the University of North Carolina at Charlotte. 'His body is cantilevering, but he's fortunate at one point to get his left foot on the ground to brace against the momentum of the football striking his hand.'
Grounding one foot also kept Beckham from over-rotating away from the precise path of the spinning football, which would have most likely caused the football to deflect away from him. The fact that the pass was a tight spiral helped considerably, too.
'It's the gyroscopic effect,' Gates said. 'It means the ball will likely stay on the same line, and that makes it easier for the human eye to see where the center of the ball is headed, which makes it easier to catch.'
When Beckham reached for the ball, it was mostly behind him, and he probably could no longer see it. But he got a little luck. His hand came in contact directly opposite the laces on the football.
'A big break,' Goff said. 'It allowed direct contact with the leather of the football and not the irregular laces. That meant an enormous amount of static friction between the glove and the ball.'
An N.F.L. football weighs slightly less than a pound. To stop an object of that weight that was traveling at 46 miles an hour, Beckham had to exert force equal to about 20 times the weight of the ball to generate enough friction, Goff said.
'So in about two-tenths of a second, with his forefinger, middle finger and right thumb, he applied about 10 pounds of pressure on the ball,' Goff said. 'That's really hard to do, especially when you're falling down.'
Added Schmitz: 'He also had to let the tip of the football pass through his hand first so that he grabbed the ball toward its center. His grip on the ball ended up like a quarterback might grip the ball to throw it.'
The glove Beckham wore, a Nike Vapor Jet 3.0 model, also played a significant role in corralling the pass. The gloves, which sell for $100 a pair, have overlays of a tacky mesh in the palm and curved fingers that mimic the natural bends of the hand. Beckham, his teammate Victor Cruz, Dallas's Dez Bryant and Arizona's Larry Fitzgerald have worked with Nike to help design the glove. Testing various materials for the glove by simulating a thrown football in a lab allows the manufacturer to raise the glove's coefficient of friction as high as possible. In other words, engineering can make the ball stop in a wide receiver's hands more quickly.
'Unless the gloves are wet from sweat or rain,' Goff said. 'If Beckham's gloves weren't dry last night, that pass probably slips through his hands.'
But that is not what happened.
Instead, millions of American sports fans marveled at a catch that was instantly being considered one of the best catches in football history. The catch it has most often been compared to was the one made by the Giants' David Tyree in the Super Bowl XLII.
Since Tyree pinned the football to his helmet as he toppled to the ground, physicists had a field day assessing that pass reception, too.
'The Tyree catch was in a big game, so it's a bigger moment, but it involved a little luck,' Goff said. 'The helmet helped to stop the football. In terms of pure, linear athleticism, this was better. Beckham caught it all on his own. He made the whole thing happen.'
Post By http://www.nytimes.com/2014/11/25/sports/football/a-lab-perfect-reception-by-the-giants-odell-beckham-jr.html
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