Ch.19 Earth, Moon, & Sun

Section 3: Phases, Eclipses, & Tides

Section 3

• Motions of the Moon– The changing relative positions of the moon,

Earth, and sun cause the phases of the moon, eclipses, and tides

Section 3

• Phases of the Moon– Phases– The phase of the moon you seed depends on how

much of the sunlit side of the moon faces Earth– What is a new moon?

Section 3

• Eclipses (when an object in space comes between the sun and third object, it casts a shadow on the object– When the moon’s shadow hits Earth or Earth’s

shadow hits the moon, an eclipse occurs– Two types of eclipses• Solar eclipses• Lunar eclipses

Section 3

• Eclipses– When Do Solar Eclipses Occur• A solar eclipse occurs when the moon phases directly

between Earth and the sun, blocking sunlight from Earth• Solar eclipse

– Total Solar Eclipses• Umbra

– Partial Solar Eclipses• Penumbra

Section 3

• Eclipses– When Do Lunar Eclipses Occur• Lunar eclipses• During a lunar eclipse, Earth blocks sunlight from

reaching the moon

– Total Lunar Eclipses– Partial Lunar Eclipses– During which phase of the moon can lunar

eclipses occur?

Section 3

• Tides (the rise & fall of ocean water that occurs every 12.5 hrs or so)– Tides are caused mainly by differences in how

much the moon’s gravity pulls on different parts of Earth

– The Tide Cycle– Spring Tides– Neap Tides