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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