Dawn vs. Dusk

Main Difference

The main difference between Dawn and Dusk is that the Dawn is a time that marks the beginning of the twilight before sunrise and Dusk is a darkest stage of twilight, or at the very end of astronomical twilight after sunset and just before night.

• Dawn

  Dawn, from an Old English verb dagian: “to become day”, is the time that marks the beginning of twilight before sunrise. It is recognized by the appearance of indirect sunlight being scattered in the atmosphere, when the centre of the Sun’s disc reaches 18° below the horizon. This dawn twilight period will last until sunrise (when the Sun’s upper limb breaks the horizon), as the diffused light becomes direct sunlight.

• Dusk

  Dusk occurs at the darkest stage of twilight, or at the very end of astronomical twilight after sunset and just before night. Pre-dusk, during early to intermediate stages of twilight, there may be enough light in the sky under clear conditions to read outdoors without artificial illumination, but at the end of civil twilight, when Earth rotates to a point at which the center of the Sun is 6° below the local horizon, artificial illumination is required to read outside. The term dusk usually refers to astronomical dusk, or the darkest part of twilight before night begins.