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The bright initial flash of a nuclear weapon is the first indication of a nuclear explosion, traveling faster than the blast wave or sound wave. [6] "A 1-megaton explosion can cause flash blindness at distances as great as 13 miles (21 km) on a clear day, or 53 miles (85 km) on a clear night.
Pressure phosphenes can persist briefly after the rubbing stops and the eyes are opened, allowing the phosphenes to be seen on the visual scene. Hermann von Helmholtz and others have published drawings of their pressure phosphenes. One example of a pressure phosphene is demonstrated by gently pressing the side of one's eye and observing a ...
Afterglow with its bright segment and purple light above, interrupted by crepuscular rays. An afterglow in meteorology consists of several atmospheric optical phenomena, with a general definition as a broad arch of whitish or pinkish sunlight in the twilight sky, consisting of the bright segment and the purple light.
Glow in the dark material is added to the plastic blend used in injection molds to make some disc golf discs, which allow the game to be played at night. Often clock faces of watches are painted with phosphorescent colours. Therefore, they can be used in absolute dark environments for several hours after having been exposed to bright light.
In photography, the golden hour is the period of daytime shortly after sunrise or before sunset, during which daylight is redder and softer than when the sun is higher in the sky. The golden hour is also sometimes called the magic hour, especially by cinematographers and photographers.
The meaning of these gorgeous flowers varies depending on the hue. Purple lilacs represent the first emotions of love while magenta lilacs symbolize love and passion, perfect for a more serious lover.
Civil, nautical, and astronomical twilight. [3] Dusk is the darkest part of evening twilight. The time of dusk is the moment at the very end of astronomical twilight, just before the minimum brightness of the night sky sets in, or may be thought of as the darkest part of evening twilight. [4]
The human eye can function from very dark to very bright levels of light; its sensing capabilities reach across nine orders of magnitude.This means that the brightest and the darkest light signal that the eye can sense are a factor of roughly 1,000,000,000 apart.