Back

SPACE EXPLORATION
Lesson 1 - Page 5

Next 

Newton (1642-1727) used a new type of reflecting telescope, as well as other instruments, to observe and calculate the orbits of planets and satellites that would be the basis for his laws of motion and gravity. He could now see more than any scientist before him. Newton's law of motion would take astronomy to a new scientific level. Newton's first law of motion may be stated simply that a body remains at rest or continues to move with constant velocity in a straight line unless it is acted on by an unbalanced outside force. The second law of motion states that the change of speed or direction of a body (acceleration) is directly proportional to the external force producing the change. The third law of motion is that every action has an opposite and equal reaction.


Sir Isaac Newton, 1689

   Back

[Back to Space Exploration]  [Earth Science Grid]

Next