1. Record the space vocabulary words and entire definition on page 70-74 in your notebook.

2. Solar System/Space Vocabulary

3. Sun A medium sized star that is about halfway through its lifespan. It provides a pulling force called gravity, keeping space objects in orbit around itself.

4. Heliosphere The place where the solar winds from the Sun mix with the winds from other stars. The heliosphere extends out from the Sun to distance of about 15 million miles.

5. Asteroid Asteroids-rocky leftovers of planet formation. They are located in the asteroid belt between Jupiter and Mars Meteorites are pieces of asteroids - or sometimes planets or the Moon.

6. Meteoroid/Meteor/Meteorite Asteroids that are on a collision course with Earth are called meteoroids. When a meteoroid strikes our atmosphere at a high velocity, friction causes this chunk of space matter to vaporize. A meteor is small body of matter from outer space that enters the earth's atmosphere, appearing as a streak of light (shooting star). Any part of the meteoroid that does not burn up and strikes Earth’s surface is called a meteorite.

7. Solar System The collection of planets and their moons in orbit around a sun, together with smaller bodies such as asteroids, meteoroids, comets and minor planets.

8. Kuiper Belt This belt is beyond orbit of the dwarf planet Pluto and contains millions of small objects that have different composition than asteroids (icy) and different orbit (circular) than comets.

9. Oort Cloud It is not a cloud but an area containing a trillion comets. These comets do not orbit the Sun in a ring but each comet can arrive in the Solar System from any direction and orbit the Sun.

10. Comet Called “dirty snowballs.” They are a mixture of water, gas ices and rock. They travel in a huge oval orbit around the Sun. When its orbit brings it close to the Sun, the dust and ice heat up to produce a “tail”.

11. Astronomical Unit (AU) This is the distance between the Earth and the Sun that is used as a standard measurement for the huge distances in space.

12. Model A small object, usually built to scale, that represents in detail another, often larger object.