Do we have the 4 seasons because the sun is not exactly in the centre of earths orbit and so the distance changes from the sun as we go from summer to winter ?
Thanks
2007-12-07 20:59:54 · 6 answers · asked by Andy 3 in Science & Mathematics ➔ Astronomy & Space
The Earth's orbit is elliptical (Similar to egg shaped) and it is tilted on its axis at around 23 degrees but this does change from time to time.
As we are now in December we are on our closest passing to the sun. The Southern hemisphere is tiled towards the sun (summertime) and the northern hemisphere away from the sun (Winter time). If you concentrate on just the axis the axis tilts like this / but stays constant. Here is how to see the affect of this tilt. Take a pen or a pencil and tilt it in a similar way then without changing the angle or the way in which it lies move it around your finger. This will then show you what happens in a general sense. Depending on which pole is pointing towards the sun dictates which hemisphere gets its summer or winter. periods between gives spring or autumn/fall. Again this is dictated by which pole will be pointing towards the sun at summertime.
This phenomenon also explains why in summer the days get longer and the nights get shorter. Likewise in winter the days get shorter and the nights get longer. The closer you live to the equator though, makes hardly any difference to the daylight or seasons. The opposite is true the closer you live to one of the poles.
2007-12-07 21:23:08 · answer #1 · answered by tunisianboy46 5 · 2⤊ 1⤋
The seasons are defined by the apparent position of the Sun in the sky, which changes as a result of the Earth moving around the Sun in its orbit, and the tilt of the Earth on it's axis.
The elliptical orbit of the Earth has a small effect on the overall temperatures. There is a difference of about 3.1 million miles from when the Earth is closest to the Sun (usually about the 4th of January) and when it is it's farthest ( about July 4th).
The majority of the seasonal variation of temperatures is due to the Earth's tilt on it's axis. The Sun's apparent position in the sky is it's highest at the Summer Solstice, and lowest at the Winter Solstice. The equinoxes (Spring and Fall) are defined as the moment the Sun appears to be overhead at some spot on the Equator.
2007-12-07 23:47:19 · answer #2 · answered by cyswxman 7 · 0⤊ 0⤋
No, we have seasons because of Earth's axial tilt of 23 and 1/2 degrees. During part of Earth's orbit, this causes the northern hemisphere to tilt toward the sun, thus receiving more direct rays from it and causing summer in the north. Six months later, the opposite is the case - the southern hemisphere tilts toward the sun, and it's summer down under.
2007-12-08 00:21:35 · answer #3 · answered by Anonymous · 0⤊ 0⤋
No. It's because the Earth is tilted on its axis. For half of the Earth's orbit around the sun the north pole is pointing towards th sun, and for the other half of the year the south pole is pointing towards the sun. The hemisphere nearer the sun experiences summer and the other experiences winter.
2007-12-07 21:06:10 · answer #4 · answered by andy muso 6 · 6⤊ 0⤋
Yes, that and the fact that the Earth is not spinning on an axis that is perpendicular to the orbit's path. The Earth is spinning on a tilted axis such that part of the Earth is tilted toward the Sun in Summer and away from it in Winter.
2007-12-07 21:48:26 · answer #5 · answered by zahbudar 6 · 0⤊ 1⤋
I am from planet Earth. I eat meat and elephant and sometimes I get tired and sleep on the grass. I like tv. Sometimes I go to movie to see movie.
Will you one day visit me on Mars.
2007-12-07 21:03:01 · answer #6 · answered by Anonymous · 0⤊ 8⤋