SPACE AND BEYOND http app discoveryeducation comsearch Nttsolarsystem

SPACE AND BEYOND http: //app. discoveryeducation. com/search ? Ntt=solar+system#

GEOCENTRIC MODEL

GEOCENTRIC FACTS • • • Earth at center Earth motionless Uniform motion on circles for celestial objects Sky-entire heavens (all “spheres”) moves westward daily relative to horizon Made of a special material Division of earth/sky by matter and motions Moon- “sphere” moves eastward relative to the stars in a month Sun’s “sphere” moves eastward in a year relative to the stars Each planet’s “sphere” moves eastward relative to stars Order based on decreasing average angular speed: Mercury, Venus, Sun, Mars, Jupiter,

HELIOCENTRIC MODEL

HELIOCENTRIC FACTS Copernicus & Galileo • Sky-daily rotation of earth eastward (west to east) • Moon- eastward revolution of moon about earth monthly • Sun-reflection of earth’s yearly eastward revolution around sun • Planets-each revolves eastward around sun; earth third; natural motion, no forces! • Greater distance from sun, longer period of revolution • Natural order of planets from sun from periods • Relative distances from observations and geometry

GEOCENTRIC VS HELIOCENTRIC

INNER PLANETS Mercury - Mercury is the planet closest to the Sun. Venus - Venus is the second planet from the Sun. It is the hottest planet. Earth - Earth is the third planet from the Sun and the planet we live on. Mars - Mars is a red planet and the fourth planet from the Sun.

ASTEROID BELT • Asteroids are sometimes called minor planets because the are made up of rocks and metal. • The rocks come in many sizes. Larger rocks are Asteroids. They are found in large areas between the orbits of Mars And Jupiter • This is the division between the inner and out planets

OUTER PLANETS • Jupiter - Jupiter is the fifth planet from the Sun. This gas giant is the largest planet. • Saturn - Saturn is the sixth planet from the Sun. This gas giant has large, beautiful rings. • Uranus - Uranus is a gas giant and is the seventh planet from the Sun. • Neptune - Neptune is a gas giant and is usually the eighth planet from the Sun.

HOW DO THE PLANETS MOVE All planets move around the sun in the west to east direction that is in the anticlockwise direction.

DISTANCES IN SPACE • You know what a kilometer is – you can walk that distance easily. • You know what 100 km is – that’s how far a car could travel in an hour at the speed limit on a main road. • Travel more than 100 km above the surface of the Earth, and you’re in space, at the edge of the atmosphere. • When the Space Shuttle goes into space, it orbits about 700 km above the surface of the Earth • The Moon is 400, 000 km away. That’s the same distance as 10 times round the Earth. • Numbers start getting really big when we look at distances from Earth to other planets in our Solar

LIGHT YEARS • We need a different unit of measurement, because at these distances, kilometers are too small to be much use. • One unit for measuring very big distances is the light year. • This is the distance that light travels in a year, so 1 light year is about 9, 500, 000, 000 km.

WHAT ARE THE TIDES? • Tides are the daily rise and fall of Earth’s waters on its coastlines. • As the tide comes in, the level of the water on the beach rises gradually. • When the water reaches its highest point, it is high tide. • Then the tide goes out, flowing back toward the sea. • When the water reaches its lowest point, it is low tide.

Tides are caused by the interaction of Earth, the moon, and the sun…. their gravitational pull on each other.

As a result of the moon pulling on Earth and its waters, two big bulges of water form: one directly under the moon and another on the exact opposite side of the moon As the Earth spins, the bulges follow the moon.

• Spring tide : occur at each new moon and each full moon. • Because the sun and moon are lined up at these points, the gravitational attraction is greater than usual, thus producing high than usual high tides and lower than usual low tides. • It produces the greatest

• Neap tides occur at the first and third quarter of the moon (exactly between full and new moon) where the moon and sun are pulling at right angles. • These tides have the least difference between high and low tide or the