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NASA’s Puffi n is designed to carry a single passenger.


Puffi n lifts off like a rocket. Once in the air, it turns to move horizontally across the sky.


WORDWISE


drag: a force that pulls on and slows down an object’s movement


gravity: a force that pulls everything toward Earth’s center


lift: a force that pushes an object upward


thrust: a force that pushes an object forward


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