Do days lengthen and shorten at a constant rate?

Answer 1

The earth undergoes a number of motions. The motion around the polar

axis accounts for the length of days and nights. The motion around the sun accounts for

the length of the year. Of interest here is the rotation of earth on the polar axis. The primary contributor to the differences we see in the length of periods of daylight is the tilt in earth's axis. You have noticed that globes of the earth are virtually always set on frames with the north-south pole oriented at an angle (of about 22.4 degrees). This is not because the tilt is more visually appealing. The earth is actually tilted that way, measured against the plane that contains the earth's whole orbit. When people in the south are experiencing summer around December-March, the south pole is tilted toward the sun. In the middle of the south temperate zone, more than half of your line of latitude will be in the sun at any moment. This is because of the tilt. As the earth rotates anyone at that latitude will spend more than half the day in sunlight. At the related latitude in the north, less than half the day will be in the sun. This all cycles back and forth as the earth orbits the sun, the axis maintaining its point almost exactly in the same direction.

Answer 2

Because the earth is tilted at 23.5° and as it orbits the sun different parts of the earth are nearer to the sun, making it seem higher in the sky or lower in the sky. The closer you are to the the equator, the less of a difference there is in the length of the day throughout the year. By the December 21st, the northern hemisphere is tilted as far away as it can be, making the days shortest in the northern hemisphere and longest in the southern hemisphere. by June 21st, the northern hemisphere is tilted at the maximum towards the sun and the longest days are in the northern hemisphere.

Answer 3

No, they are not. Regarding Universal Coordinated Time (UTC), what used to be called Greenwich Mean Time, there are occasional leap seconds added to a day, meaning that even relative to UTC not all days are the same length. Of course, periods of sunlight vary according to season depending on your latitude. Even with regard to solar days, the period of time between successive transits of the sun at a given spot, days are not the same length. This is because of the earth's changing orbital velocity over the course of a year.

Answer 4

No, near the longest and shortest days of the year in December and June, the length of the day from day to day varies by a very small amount. Near the Equinoxes, during October or March, the length of the day from day to day varies a lot. If you plotted day length on a graph for the year, it would look like a sine wave.

Answer 5

Because the earth is tilted at 23.5° and as it orbits the sun different parts of the earth are nearer to the sun, making it seem higher in the sky or lower in the sky. The closer you are to the the equator, the less of a difference there is in the length of the day throughout the year. By the December 21st, the northern hemisphere is tilted as far away as it can be, making the days shortest in the northern hemisphere and longest in the southern hemisphere. by June 21st, the northern hemisphere is tilted at the maximum towards the sun and the longest days are in the northern hemisphere.

Answer 6

No, the lengthening and shortening of days is not a constant rate. It varies throughout the year due to the tilt of the Earth's axis as it orbits the Sun. This results in the changing seasons and varying lengths of daylight.