The Solar System The “Final Frontier”

The Night Sky  When you look up into the sky at night, you see the moon, but there are also other things that are seen…what do you think these things are? Planets and stars!  The moon, stars, and planets seem to move across the sky at night, but what is actually happening? As our planet rotates on its axis and revolves around the sun, it appears that objects in space are moving across the sky. Actually, the Earth is rotating on its axis making it APPEAR that they move across the sky.

Out of this World Vocabulary  Planet - A celestial body larger than an asteroid or comet that reflects light from a star and revolves around that star  Star - A celestial body that creates heat and light energy  Meteor – A bright trail or streak that appears in the sky when a meteoroid is heated to glowing by friction with the earth's atmosphere. Also called falling star, meteor burst, shooting star.

Out of this World Vocabulary Continued…  Comet –A celestial body, observed only in that part of its orbit that is relatively close to the sun. Comets are thought to consist chiefly of ammonia, methane, carbon dioxide, and water.  Asteroid - An asteroid is a bit of rock.

Out of this World Vocabulary Continued…  Solar System - The sun together with the nine planets and all other celestial bodies that orbit the sun  Galaxy –Any of numerous collections of stars, gas, and dust that make up the visible universe

Our Place in Space  The planet that we live on is Earth.  The Earth, 8 planets, sun, moons, one dwarf planet, asteroids, and comets make up our solar system.  Our solar system is in a spiral galaxy called the Milky Way.  The spiral galaxy named the Milky Way has five arms. The arm where our solar system is located is called the Orion Arm.

Let’s see a picture of our galaxy! This picture was taken from the following site:

Our Solar System  As we have learned, our solar system is made up of the sun, 8 planets, 1 dwarf planet, moons, comets, and asteroids  The sun, 8 planets, 1 dwarf planet, moons, comets, and asteroids all rotate and revolve at different rates of speed  Let’s observe the planets of our solar system a little more closely!

The Sun  Solar System means “STAR system.” Our solar system only has ONE star.  As we know, the sun is a STAR!

Inner Planets of our Solar System  Mercury  Venus

Inner Planets of our Solar System Continued...  Earth  Mars

The Asteroid Belt  An asteroid is a bit of rock. It can be thought of as what was "left over" after the Sun and all the planets were formed. Most of the asteroids in our solar system can be found orbiting the Sun between the orbits of Mars and Jupiter. This area is sometimes called the "asteroid belt".  Think about it this way: the asteroid belt is a big highway in a circle around the Sun. Think about the asteroids as cars on the highway. Sometimes, the asteroid cars run into one another. When this happens, the asteroids may break up into smaller asteroids. Scientists think that most asteroids are the result of collisions between larger rocky space bodies.

The Asteroid Belt  Asteroids can be a few feet to several hundred miles wide. The belt probably contains at least 40,000 asteroids that are more than 0.5 miles across.  If an asteroid is captured by the gravitational pull of a planet, the asteroid can be pulled out of the belt and go into orbit as a moon around the planet that pulled on it.

The Asteroid Belt

Outer Planets of our Solar System Continued...  Jupiter  Saturn

Outer Planets of our Solar System Continued...  Uranus  Neptune

Outer Planets of our Solar System Continued…  Pluto (dwarf planet)

Comets Comets are dark, solid bodies a few kilometers across that orbit the Sun in eccentric paths. Comets can be described as "dirty snowballs" containing a mixture of dust and frozen gases. Some of the icy material evaporates as the comet nears the Sun, creating an envelope of gas and dust that enshrouds the solid body.

How big are the planets in relation to the sun? What is the biggest/smallest planet?

Remember, ALL 9 planets REVOLVE around the Sun!!! (Notice the orbits)

Memorize the Planets in their correct order starting with the sun!!! AA memory strategy: My Very Excellent Mother Just Served Us Nine Pizzas (Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, Pluto) Let’s watch a video to learn more about our solar system!