The amount of time in a moment is 90 seconds, or one and a half minutes, according to its usage as a unit of time measurement in medieval times dating back to the 8th century. This was based on the positioning of shadows on a sun dial, in which shadows moved along the dial 40 times in an hour. After the invention of the mechanical clock in the 13th century, a moment was no longer widely used as a specific unit of measurement. Going forward in modern times, a moment began to be used as a figure of speech to refer vaguely to any very brief period of time.
More about measurements of time:
Time has been measured since at least 1500 BC, which is the first instance of records indicating time measurement through the invention of the sundial by the ancient Egyptians.
The word clock comes from the medieval Latin word for bell and refers to the bell that was used to signal that it was time for monks to pray.
The poet Miroslav Holub proposed in 1990 that a moment is the unit of time it takes a person to read a average line of verse.