USA HISTORY

Detailed explanation-1: -: the first appearance of light in the morning followed by sunrise.

Detailed explanation-2: -Dawn is the time of morning when the Sun is 6° below the horizon. Respectively, dusk occurs when the Sun is 6° below the horizon in the evening. Sunrise is the time when the first part of the Sun becomes visible in the morning at a given location.

Detailed explanation-3: -Dawn is the time that marks the beginning of twilight before sunrise. It is recognized by the appearance of indirect sunlight being scattered in Earth’s atmosphere, when the centre of the Sun’s disc has reached 18° below the observer’s horizon.

Detailed explanation-4: -The dawn of a period of time or a situation is the beginning of it. [literary]

Detailed explanation-5: -It occurs the moment the disc of sun completely disappears below the western horizon. Technically, “dusk” is the period of twilight between complete darkness and sunrise (or sunset). In common usage, “dawn” refers to morning, while “dusk” refers only to the evening twilight.