Seasons

What does earth's constant rotation cause us to experience. night and day How long does it take earth to complete one rotation 24hr From which direction does the sun rise. east From which direction does the sun set.west What do you think would happen if the Earth stopped rotating? How would this effect human life light

Key Concept about Earth's rotation: The Earth always spins at the same speed (about 1000 miles per hour!)

The other, darker half has night. As the Earth spins, we move through the light, into the darkness, and back again. This makes day and night. Half of the Earth is always in the light and half of the Earth is always in the dark

Key Concept: Which produces more heat? Which produces less? direct light
 * Direct Light || Angled or Indirect light ||
 * more heat || less heat ||

Winter" comes to us from the Old English word "wintar" and perhaps Lithuanian 'vanduo' -- meaning water, and likely coming from the stormy, snowy time of the year. "Spring" simply appears to have its origins as a time when plants "spring up" and old English "springan" which is "to leap and burst forth." "Summer" comes from the Old English word "Sumor" which meant the "hot season of the year." "Autumn" is more difficult. It came from the Latin word "Autumnus." The Elizabethans than casually used "fall" around the 16th Century to denote it as the time when the leaves fall. Both terms were brought to America when the English colonized it, but fall eventually won out here, while "autumn" is still the word of choice in England.



Northern Hemisphere


 * winter || spring || summer || fall ||
 * in direct || equal || direct || equal ||

Southern Hemisphere


 * winter || spring || summer || fall ||
 * in direct || equal || direct || equal ||


 * Summer**

The day the north pole is nearest the Sun is called the 'summer solstice'. (You can see this from the picture on the right). Looking from Earth, the Sun reaches its highest point in the sky all year. This means it takes the most amount of time to cross the sky. So this is the longest day of the year and happens around 21 June. Astronomers call this the start of summer and after this date, days start getting shorter.
 * Autumn**

As we continue our journey around the Sun, the north pole moves away from the Sun. The Sun rises lower in the sky so the days continue getting shorter. When the Sun is at its mid-point in the sky, we reach the 'autumn equinox', around 22 September. Day and night are both 12 hours long and its the beginning of autumn.
 * Winter**

The day when the north pole is furthest from the Sun is called the 'winter solstice'. The Sun crosses the sky at its lowest point all year. Therefore it crosses the sky in the quickest time so this is the shortest day of the year. Winter solstice happens around 22 December and marks the start of winter. From then on, the days start getting longer.
 * Spring**

The Earth continues on its path, and our north pole starts moving towards the Sun again. The Sun moves upwards in our skies and the days continue getting longer. Again, we reach a midpoint when day and night are both 12 hours long. This is called the 'vernal (or spring) equinox' and happens around 21 March.

Sun is at the midpoint of the sky. || the longest day of the year, when the Sun is at its most northern point in the sky. || day and night are each 12 hours long and the Sun is at the midpoint of the sky. ||
 * || winter solstice || spring equinox || summer solstice || fall equinox ||
 * Describe the amount of daylight ||~ the shortest day of the year when the sun is at its most southern point in the sky. || day and night are each 12 hours long and the
 * Date || 22 December || 21 March. || 21 June || 22 September. ||