<em>Another key factor that determines a star's colour is its temperature. As stars become hotter, the overall radiated energy increases, and the peak of the curve changes to shorter wavelengths. To put it another way, when a star heats up, the light it produces moves toward the blue end of the spectrum.</em>
Speed is the time it takes something to travel a certain distance. Accelaration is the rate at which an object's speed changes. Velocity is a vector of the object's speed and direction.
