The calendar is such a routine, ordinary thing, but how much do you really know about the operation of it. Why is it like that?
A DAY: The Earth rotates at a reasonably fixed pace about the imaginary line running between the North and South Poles named the Earth's Axis. The time it takes to spin once is called a 'rotation' and this takes just under twenty-four hours. Nevertheless, because the Earth is constantly traveling around the Sun, the exact time from noon one day to noon the next is 3 minutes 56 seconds longer and this makes a day almost exactly twenty-four hours in length.
The actual time from noon to noon differs depending where the Earth is on its celestial course around the Sun, but if you average the days in a year out, it comes to exactly twenty-four hours.
A YEAR: All nine planets in our solar system move around the Sun in approximately perfectly circular routes called orbits. Each trip around the Sun is called a revolution and all the planets orbit around the Sun in the same direction. The course the Earth takes can be verified by noting its location against the background stars.
In view of the fact that you cannot see the Sun and the stars at the same time, it is necessary to note the position of the Sun in the morning and the see which stars come out there in the night. You will see that the Sun seems to pass through the twelve constellations of the zodiac during a year.
Earth's trip around the Sun, which seems like the Sun traveling through the zodiac takes about 365.25 days. This is different from year to year, so astronomers add or delete a second in some years to keep their time correct with the Earth's motion.
THE SEASONS: The seasons indicate the variation in the pattern of daylight over the course of a year. Because the Earth is tilted off centre, different parts of it get different amounts of sunlight on different stages of its path around the Sun, a path that we call a year. So, between about the 21st September and late March, the Earth's Northern Hemisphere is tilted away from the Sun, which creates Autumn and Winter, giving less than twelve hours of daylight per day.
From April to the 20th September, the Northern Hemisphere receives more than twelve hours of daylight a day, creating Spring and Summer. The exact opposite happens in the Southern Hemisphere.
The Equinoxes occur at the points in the year when there is exactly twelve hours of sunlight and darkness in the day. So, the vernal or Spring equinox is on or around the 21st March and the autumnal equinox is on or around the 21st September. Summer officially begins on the day with the greatest amount of daylight, the 21st June or summer solstice.
The winter solstice is on the shortest day, the 21st December. 'Solstice' is a combination of two words meaning 'sun standing still' and the days are so named because they are the days when the apparent movement of the Sun reaches its limits and reverses direction again.
A DAY: The Earth rotates at a reasonably fixed pace about the imaginary line running between the North and South Poles named the Earth's Axis. The time it takes to spin once is called a 'rotation' and this takes just under twenty-four hours. Nevertheless, because the Earth is constantly traveling around the Sun, the exact time from noon one day to noon the next is 3 minutes 56 seconds longer and this makes a day almost exactly twenty-four hours in length.
The actual time from noon to noon differs depending where the Earth is on its celestial course around the Sun, but if you average the days in a year out, it comes to exactly twenty-four hours.
A YEAR: All nine planets in our solar system move around the Sun in approximately perfectly circular routes called orbits. Each trip around the Sun is called a revolution and all the planets orbit around the Sun in the same direction. The course the Earth takes can be verified by noting its location against the background stars.
In view of the fact that you cannot see the Sun and the stars at the same time, it is necessary to note the position of the Sun in the morning and the see which stars come out there in the night. You will see that the Sun seems to pass through the twelve constellations of the zodiac during a year.
Earth's trip around the Sun, which seems like the Sun traveling through the zodiac takes about 365.25 days. This is different from year to year, so astronomers add or delete a second in some years to keep their time correct with the Earth's motion.
THE SEASONS: The seasons indicate the variation in the pattern of daylight over the course of a year. Because the Earth is tilted off centre, different parts of it get different amounts of sunlight on different stages of its path around the Sun, a path that we call a year. So, between about the 21st September and late March, the Earth's Northern Hemisphere is tilted away from the Sun, which creates Autumn and Winter, giving less than twelve hours of daylight per day.
From April to the 20th September, the Northern Hemisphere receives more than twelve hours of daylight a day, creating Spring and Summer. The exact opposite happens in the Southern Hemisphere.
The Equinoxes occur at the points in the year when there is exactly twelve hours of sunlight and darkness in the day. So, the vernal or Spring equinox is on or around the 21st March and the autumnal equinox is on or around the 21st September. Summer officially begins on the day with the greatest amount of daylight, the 21st June or summer solstice.
The winter solstice is on the shortest day, the 21st December. 'Solstice' is a combination of two words meaning 'sun standing still' and the days are so named because they are the days when the apparent movement of the Sun reaches its limits and reverses direction again.
About the Author:
Owen Jones, the writer of this article, writes on many subjects, but is currently involved with researching Franklin planner pages. If you have an interest in calendars, organizers or promotional calendars, please go over to our website now at Promotional Desk Calendars
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