Date Vocabulary Revolution: The motion of one body around another; such as Earth in its orbit around the Sun; the time it takes an object to go around once. Rotation: the action or process of rotating on or as if on an axis or center; one complete turn Announcements:

Earth’s Movement

PA Standard S8.D.3.1.1 Describe patterns of earth’s movements (i.e., rotation and revolution) in relation to the moon and sun (i.e. phases, eclipses, and tides)

Earth’s Revolution In astronomy, a revolution is the motion of one object around another. It takes 365 days for the Earth to revolve around the Sun.

A Discussion of Earth’s Revolution around the Sun… If I were to set up a model of the Earth-Sun system, where should the Sun be? Where should the Earth be? Earth has a North Pole and a South Pole. These are the North and South ends of an imaginary axle called the axis on which the Earth rotates

Earth Rotates on it’s axis… Watch how I can turn the globe like top. This kind of motion is called a rotation Notice that the Earth does not spin straight up and down on its axis, but is tipped over at a significant angle of 23.5 degrees How long does it take for Earth to rotate on its axis?

A trip around the Sun… Participate and answer questions about the Earth’s revolution of the Sun on your worksheet.

Equinox: when sunlight shines equally on the northern and southern hemispheres The fall or autumnal equinox occurs around September 21st and marks the beginning of the Fall in the Northern Hemisphere The spring or vernal equinox occurs around March 21st and marks the beginning of the spring in the Northern Hemisphere

Solstice: the area of sunlight is at a maximum in one hemisphere and a minimum in another The Winter solstice occurs around December 21st and marks the beginning of the winter season in the Northern Hemisphere (This is the shortest day of the year!) The Summer solstice occurs around June 21st and marks the beginning of the summer season in the Northern Hemisphere. (This is the longest day of the year!)

Recap 1. How does the Earth move around the Sun and how long does it take? 2. What are the longest and shortest days of the year? 3. What are vernal and autumnal equinoxes?