Unit 8 Earth in Space Seasons and Tides

The reasons for the seasons Fall Equinox Summer Solstice Spring Equinox Winter Solstice

The reasons for the seasons Earth’s Tilt Fall Equinox Summer Solstice Spring Equinox Winter Solstice SUN

Equinox Solstice Ecliptic Plane When the days and nights are ~ equal length (March and September) When Sun is furthest or closest to the Earth’s poles The plane in which the planets in our solar system orbit the Sun

Aphelion Perihelion When Earth is furthest from Sun with slowest revolution When Earth is closest to Sun with fastest revolution

Bell Work: How will precession affect the seasons? Fall Equinox SUN Summer Solstice Spring Equinox January 2015 January 15,015

Earth And its Moon The Moon Orbits the Earth once every 27.3 days. The Moon and Earth orbit about the barycenter

Lunar Eclipse When the Moon is FURTHEST from the Sun and on the ecliptic plane

Solar Eclipse When the Moon is CLOSEST to the Sun and on the ecliptic plane

Earth And its Moon Gravity from the Moon and Sun cause ocean tides on Earth When Sun-Earth-Moon are lined up the tides are the highest and the lowest.

When Sun-Earth-Moon form a right angle the high tides are at their lowest and the low tides are at their highest.

Spring Tides: When Earth, Sun and Moon are aligned; during full and new moons

Neap Tides: When Sun and Moon form right angles to Earth; during quarter moons

Diurnal Tides 1 high tide and 1 low tide each lunar day. (1 lunar day = 24hrs 50min) Seen in many areas of the Gulf of Mexico

Semi-diurnal Tides 2 high tides and 2 low tides of equal size each lunar day. Seen along the East Coast of N. America

Mixed Semi-diurnal Tides 2 high tides and 2 low tides of unequal size each lunar day. Seen along the West Coast of N. America

First Quarter Moon New Moon Third Quarter Moon