Scientists with the National Aeronautics and Space Administration (NASA) realized a nearly 40-year-old dream in July 1999, when Deep Space 1 (DS-1), the first spacecraft to employ an ion engine as its main propulsion system, made a successful fly-by of an asteroid.
HISTORY OF PHYSICAL SCIENCE
The history of physical science explains how some of the major physics concepts were discovered. Check out these articles on the history of physics.
More To Explore