What relationship between the earth and the sun causes the seasons to occur? | Socratic
Sun also has the most dominating influence on the changing climate of various This cycle will carry on, creating the seasons that we experience on earth. Brought to you by the National Earth Science Teachers Association The seasons are caused as the Earth, tilted on its axis, travels in a loop around As the Earth travels around the Sun, the hemisphere that is tilted towards. Sun – Earth Relationship: The Seasons. SOLAR RADIATION ON EARTH Different parts of the Earth receive different amounts of solar radiation. Which part of.
The solar day, on the other hand, is the time needed for a point on earth pointing towards a particular point on the sun to complete one rotation and return to the same point. It is defined as the time taken for the sun to move from the zenith on one day to the zenith of the next day, or from noon today to noon tomorrow.
The length of a solar day varies, and thus on the average is calculated to be 24hrs. In the course of the year, a solar day may differ to as much as 15mins. There are three reasons for this time difference.
Because of this, the sun appears to move proportionately at a constant speed across the sky. The sun thus produces a daily solar arc, which is the apparent path of the sun"s motion across the sky. At different latitudes, the sun will travel across the sky at different angles each day.
The rotation of the earth about its axis also causes the day and night phenomenon. The length of the day and night depends on the time of the year and the latitude of the location. For places in the northern hemisphere, the shortest solar day occurs around December 21 winter solstice and the longest solar day occurs around June 21 summer solstice. In theory, during the time of the equinox, the length of the day should be equal to the length of the night.
The average time the earth takes to move around the sun in approximately days. This path that the earth takes to revolve around the sun is called the elliptical path. When the sun is moving down from above the celestial equator, crosses it, then moves below it, that point of intersection between the two planes is when the Autumnal Equinox occurs. This usually happens around the 22nd of September.
When the Sun moves up from below the celestial equator to above it, the point of intersection between the sun and the celestial equator is when Spring Vernal Equinox occurs. It usually happens around the 21st of March.
During the equinoxes, all parts of the Earth experiences 12 hours of day and night and that is how equinox gets it name as equinox means equal night. Figure 1 below shows that the orbit of the Earth about the sun is not circular.
The path is elongated or ellipitcal. This means that the distance from the Earth to the sun varies through the year.
Sun Earth Relationship
Two special events are depicted in the diagram. Aphelion July 4 is when the Earth is as far away from the sun as it ever gets. Note that these events do not correspond to the coldest and hottest months for us in the Northern Hemisphere.
The purpose of this is to show that distance from the sun has nothing to do with seasons. One orbit around the sun is called a Revolution. One revolution takes days or 1 year to complete on each birthday, you have completed one more lap around the sun! Aphelion distance is 9.
Perihelion distance is 9. Figure 2 looks rather complicated.
It does, however, reveal some very important facts about the Earth and its orbit abound the sun. First note the purpleish rectangle. This represents the plane of the Earth's orbit about the sun or the Plane of the Ecliptic. We now want to measure the orientation of the Earth with respect to the plane of its orbit, the plane of the ecliptic. Now note the orange rectangle which represents the plane of the equator. We can clearly see that the two planes do not coincide.
That is to say, the Earth is tilted with respect to the plane of the ecliptic. Figure 2 also shows the Earth's axis of rotation. This deviation, or tilt, is called Inclination. We will find that this inclination is vital for seasons on Earth. Make sure to memorize the amont of inclination as we will see this number pop up time and again!
The spinning of the Earth about its axis is called Rotation. One rotation takes about 24 hours or 1 day.
What relationship between the earth and the sun causes the seasons to occur?
Figure 3 reveals two more important parts of the seasons story. This is always the case for the whole Earth, but equal parts of each hemisphere may not be in daylight and darkness. The dividing line between day and night is called the Circle of Illumination. The orientation of the circle of illumination changes with the seasons. Note in Figure 3 that the circle of illumination does not pass through the poles.
Look carefully and you will see that more of the Northern Hemisphere is in daylight than in darkness which means that the day is much longer than the night! What is important here is that the changing orientation of the circle of illumination alters the lengths of daylight and nighttime hours. The second major concept shown in Figure 3 is the Subsolar Point. Figure 3 shows a special event when the subsolar point is as far north as it ever gets, the Tropic of Cancer.
The subsolar point is where the sun's rays are most direct and, therefore, most concentrated. The concentration of the solar energy heats the surface. Important rules emerge from this fact: When the subsolar point is as far north as it can go, it is the Northern Hemisphere's Summer.
When the subsolar point is as far south as it can go, it is the Northern Hemisphere's Winter. Figure 4 is a view of the Earth from space showing the circle of illumination.
Again, you can see that half of the planet is all ways in darkness and half is in daylight. The amounts of the northern and southern hemispheres in daylight and darkness, however, may NOT be equal.
Read on and try to answer a question about this diagram posed below. Figure 5 below shows the position of the Earth relative to the sun at four times of the year. You can see that the orbit is elliptical, as described earlier, and that the Earth exhibits a tilt inclination relative to the plane of its orbit around the sun plane of the ecliptic.