As clock technology progressed and moved away from sundials, the hands of a clock continued to move in a clockwise direction. That's what everyone was used to. It made sense instantly because people were familiar with the sundial. So, if anyone every asks you why clocks run clockwise, feel free to say "just because they do.
Skip to main content News. Dustin Nelson is a News Writer with Thrillist. He holds a Guinness World Record, but has never met the fingernail lady.
The first mechanical clocks did not start appearing in Europe until around the start of the 14 th century. Prior to that, if you wanted to know what time it was, or at least get an approximation of the hour, you would need to consult a sundial — an exercise somewhat fraught with frustrations in Britain, I would have thought.
At its simplest a sundial consists of a plate and a gnomon, usually a triangular blade, whose purpose is to cast the shadow of the sun. The earliest sundials date from around BC and were used in Egyptian and Babylonian astronomy. For those of us who live in the northern hemisphere, we observe the sun rising in the east, reaching its zenith when it is in the south and setting in the west.
Tracking its movement on a compass set to magnetic north, the sun will appear to move from right to left. For a sundial to work properly north of the Equator, the point representing noon on the plate must be positioned to the north of the gnomon.
What this means is that while the shadow cast by the gnomon reflects the apparent motion of the sun through the sky, it is represented as travelling in the opposite direction, from west through north to east. It is argued that people had become accustomed to thinking about time moving from a westerly direction to the east.
If the Earth's rotation period is less than 24 hours, why don't our clocks fall out of sync with the Sun? Intermediate What would happen if we did not have a Moon? Intermediate What is the difference between nutation and precession of the Earth?
Advanced Is the Moon moving away from the Earth? When was this discovered? Intermediate Why is the time between two successive full moons different from the lunar synodic month? Random Question. What would happen if there was a collision between two white dwarfs? Most Recent. Is speed of light the same everywhere? Beginner How does Venus have sulphuric acid in it's clouds? Intermediate Why is the sun red? Beginner But seriously: what was there before the Big Bang?
Beginner How far can photons move freely in the early universe Advanced How likely is it that the Solar System has had or will have a close encounter with another star? Intermediate How do we know what we observe is x light years away? Editor's Pick. What is the universe expanding into? Intermediate What do I need to do to become an astronomer? Beginner What's the difference between astronomy and astrology?
Beginner Why is looking out into space the same as looking back in time? Beginner Can we find the place where the Big Bang happened?
0コメント