Astronomy Review How do we know the Earth

Astronomy Review

How do we know the Earth Rotates? 1. Star Trails

How do we know the Earth Rotates? 2. Coriolis effect: Wind and water curve toward the right in the Northern hemisphere, toward the left in the Southern hemisphere.

How do we know the Earth Rotates? 3. Foucault pendulum: a pendulum attached to the ceiling by a ball bearing appears to change direction, due to rotation.

How do we know the Earth Rotates? 4. Day and night

How do we know the Earth REVOLVES? • Constellations: we see different stars depending on the season. • Seasons: Seasons the combination of revolution and the Earth’s tilt causes seasons.

Do Now: Moon Phases 1. How much of the moon is always lit by the sun? ______ 2. Why do we see phases? __________________________________________ 3. How long does it take for the Moon to revolve around the Earth? ____________ 4. How long does it take the Moon to go through all its phases? ________ 5. Define waxing_________ Define waning__________

Moon Phases

Lunar Eclipse: Earth’s shadow can be seen on the moon.

Solar Eclipse: The moon is in between the Earth and the sun

Life Cycle of Stars • Medium stars: (sun) enlarge to red giant then shrink to white dwarf • High Mass Stars: Explode into a supernova

Use the star chart on your note sheet to answer the following questions. 1. What is the luminosity of Betelguese? 2. What color are the hottest stars? 3. What kind of star is the Sun?

Doppler Effect • Provides evidence that the universe is expanding • Red shift = receding = object is moving away from you. • Blue shift= object is coming toward you

Eccentricity • The rounder the orbit = the more it resembles the number 0 = the closer its eccentricity is to 0 • The flatter the orbit = the more it resembles the number 1 = the closer the eccentricity is to 1