Once Around the Sun The Story of the Seasons A WindShadow Production

The Earth orbits around the sun once every 365 days. The Science The Earth orbits around the sun once every 365 days. An orbit is the path that a planet follows around the sun.

one revolution We also keep track of how many times we go around the sun. One complete trip is a revolution.

The sun is so far away the rays that hit the Earth are parallel. axis equator Because the Earth is tilted on its axis we have seasons.

that receive the more indirect rays are cooler. So that different parts of the Earth receive the Sun’s rays at different angles. The Earth tilts on its axis. axis Summer equator Winter The parts of the Earth that receive the more direct rays are warmer. The parts of the Earth that receive the more indirect rays are cooler.

We will start our seasons here. It is the Vernal Equinox, March 20 or 21. The start of spring. .

we have a change of season. summer Summer Solstice After the Earth has traveled 1/4 of the way around its orbit we have a change of season. .

It is the Summer Solstice, June 21 or 22, . It is the Summer Solstice, June 21 or 22, the longest day of the year and the shortest night. Summer begins.

equator axis warmer colder summer Summer Solstice The Earth’s axis is tilting towards the sun and the Northern Hemisphere starts to get warmer. .

we have another change of season. Autumnal Equinox autumn After the Earth has traveled 2/4 or halfway around its orbit we have another change of season. .

The Autumnal Equinox occurs on September 22 or 23, . The Autumnal Equinox occurs on September 22 or 23, day and night are of equal length. Autumn begins.

axis . . . . . . . . . . equator . . . . . . . . Autumnal Equinox autumn . The Earth’s axis is tilting so that the Northern and Southern Hemisphere receive equal amounts of the sun’s rays.

After the Earth has traveled 3/4 of the way around one revolution Winter Solstice winter After the Earth has traveled 3/4 of the way around one revolution we have a third change of season. .

the shortest day of the year and the longest night, occurs on Winter Solstice winter . The Winter Solstice, the shortest day of the year and the longest night, occurs on December 21 or 22. Winter begins.

equator axis winter summer winter Winter Solstice . The Earth’s axis tilts the Northern Hemisphere away from the direct rays from the sun so it receives less energy.

After the Earth has traveled spring Vernal Equinox After the Earth has traveled for one complete revolution around the sun we are back where we began. .

It is the Vernal Equinox, day and night are equal in length. spring Vernal Equinox equator It is the Vernal Equinox, day and night are equal in length. Spring begins, again. .

the reason for the seasons. The tilt of the Earth is the reason for the seasons. autumn summer winter spring

Choose the words that belong in the sentence. In a 365 day period, the Earth completes one in its . a. rotation, axis b. rotation, orbit c. revolution, axis d. revolution, orbit

Look at the illustration below. equator axis What season is the location the arrow is pointing to on the Earth experiencing? a. spring b. winter c. autumn d. summer

Look at the illustration below. equator axis What season is the location the arrow is pointing to on the Earth experiencing? a. spring b. winter c. autumn d. summer

The Math orbit geometry What geometric shape is the orbit? Art - oval Math – ellipse

The Math orbit geometry What geometric shape is the sun and Earth? Math – sphere

The Math seasons’ time How long is one revolution? Math – 365 days – 12 months – 1 year

The Math seasons’ time How long is one season? Math – ~91 days – 3 months – ¼ year

The Math geometry How would we describe the sun’s rays? axis geometry equator How would we describe the sun’s rays? Math – parallel How would we describe the angle made by the equator and the axis? Math – perpendicular, intersecting, 90 degrees

The Math geometry What is the geometric name for the equator? axis geometry What is the geometric name for the equator? Math – circle What would we call it if it just went through the center of the Earth? Math – line segment - diameter