Moon Phases, and Eclipses

Moon Phases, and Eclipses

Motions of the Moon • Moon revolves around the Earth and rotates on its axis. • Takes 27.3 days to revolve around Earth. • Rotates slowly on its axis, once every 27.3 days. • Earth only sees the same side of the moon. • “Far side” always faces away.

Phases of the Moon • We see the moon because it reflects light from the sun. • The moon’s shape changes during the month causing the phases. Moon Menu

Phases of the Moon • New Moon • The sun lights the side of the moon facing away from Earth. This side of the moon that faces the Earth is dark. Moon Menu

Phases of the Moon • Waxing Crescent • You see more and more of the lighted side of the moon. Moon Menu

Phases of the Moon • First Quarter • You see half of the lighted side of the moon. • The moon is ¼ of the way through it’s orbit. Moon Menu

Phases of the Moon • Waxing Gibbous • The moon continues to wax. • The moon is called a waxing gibbous. Moon Menu

Phases of the Moon • Full Moon • The whole lit side of the moon can be seen from Earth. • This is known as a Full Moon. Moon Menu

Phases of the Moon • Waning Gibbous • The Moon now becomes darker each day. This is known as a waning gibbous Moon Menu

Phases of the Moon • Third Quarter Moon • You can see half of the moon’s lit side. The moon is ¾ of the way through it’s orbit. This is called a third quarter moon, or last quarter moon. Moon Menu

Phases of the Moon • Waning Crescent • The last phase before new moon. Moon Menu

Phases B F H A Cause C I E D Eclipses

Phases of the Moon • Phases are caused by changes in the relative positions of the moon, Earth and sun. • As the moon revolves around the Earth, we see the moon from different angles. • The phase of the moon depends on how much of the sunlit side of the moon faces Earth. Moon Menu

Phases of the Moon • The cycle begins at new moon. • The amount of light on the moon will gradually increase (Waxing) to full moon. • After full moon, the light will gradually decrease (Waning) back to new moon. Moon Menu

Objective: I will be able to describe how the Moon moves and what causes the phases. • Phases of the Moon • One lunar cycle lasts 29.5 days. Moon Menu

Eclipses • The moon’s orbit is slightly tilted. • As a result, the moon doesn’t always pass into the Earth’s shadow or the shadow from the moon isn’t cast on the Earth. Moon Menu

Eclipses • When the moon’s shadow hits the Earth or the Earth’s shadow hits the moon, an eclipse occurs. • An eclipse occurs when an object in space comes between the sun and a third object and casts a shadow on that object. Moon Menu

Solar Eclipse • Occurs when the moon is in the new moon phase and it passes between the Earth and the sun. • Blocking sunlight from the Earth. • The moon’s shadow hits the Earth. Moon Menu

Total Solar Eclipse • Occurs when the darkest part of the moon’s shadow, “the umbra” hits the Earth. • Sunlight is completely blocked in any part of this shadow. • Must be in the shadow of the umbra to see a total solar eclipse. • Stars, and the corona are visible. Moon Menu

Partial Solar Eclipse • Occurs when the less dark shadow “the penumbra” hits Earth. • People in the penumbra only see a partial eclipse. • Part of the sun is still visible. • It is not safe to look directly at the sun. Moon Menu

Lunar Eclipse • Occurs at a full moon when the Earth is directly between the moon and the sun. • Earth blocks sunlight from reaching the moon. • The moon is in the shadow and looks dark. • Can only occur during a full moon. Moon Menu

Total Lunar Eclipse • Occurs when the moon is in the Earth’s “umbra” • The dark shadow. • Can be seen anywhere on the dark side of the Earth where the moon is visible. • More likely to see a lunar eclipse than a solar eclipse. Moon Menu

Partial Lunar Eclipse • Occurs if the Earth, moon and sun are not quite in a line. • The moon only partially passes into the umbra of the Earth’s shadow. • Edge of shadow appears blurry. • Last up to 2 or 3 hours. Moon Menu

Moon Phases, and Eclipses