November 8,2010 Celestial Motions

This is all caused by Earth’s rotation! Apparent Motions stars Sun Moon The ______, ______, and ______ appear to rise in the East and set in the West. This is because Earth rotates from West to East. They appear to move at a rate of ______ degrees per hour. Stars rotate around _______ (North Star). 15 Polaris This is all caused by Earth’s rotation!

If Earth did not rotate, stars would appear to be stationary in a time exposure photograph.

Horizon – the plane you stand on. Zenith – the point right above YOU. Meridian – An imaginary line from North through the Zenith to the south. What’s up for you?

Seasons **Seasons are NOT caused by how close or far Earth is from the Sun!!!!!** Seasons on Earth are caused by Earth’s tilt on its axis and Earth’s revolution around the Sun.

The Equator

North Pole

The Tropic of Cancer

The Arctic Circle

4. At what time does the Sun reach its highest point in the sky? Noon

5. Explain why the Sun reaches its highest point in the sky in the Southern sky and is never directly overhead for an observer in Peekskill. The Sun reaches its highest point in the sky in the southern hemisphere because the Sun’s direct ray never hits above the Tropic of Cancer (23.5°N) which is south of Peekskill.

No. The Sun’s path changes with the seasons. Is the Sun’s path through the sky always the same in Peekskill? Explain No. The Sun’s path changes with the seasons. Winter Solstice Vernal Equinox Summer Solstice: The Sun’s Noon angle is increasing! Summer Solstice Autumnal Equinox Winter Solstice: The Sun’s Noon angle is decreasing!

Time of the Season – The Zombies