1. Science Chapter 10

2. Lesson 1- What Causes Earth’s Seasons?  Earth spins just like a top!  Picture a line going through the Earth from the North Pole to the South Pole. This imaginary line through Earth is called Earth’s AXIS.  The Earth spins, or ROTATES, on this tilted axis. This is called ROTATION.  It takes 1 day, or 24 hours, for the Earth to rotate.

3. Lesson 1 Continued…  The Earth also revolves around the sun. One trip around the sun is one REVOLUTION.  Each revolution takes about 365 days, or one year.

4. Lesson 1 Continued (Seasons)  During the year, some parts of Earth has four seasons- WINTER, SPRING, SUMMER, and FALL.  The tilt of Earth on its axis as it revolves around the sun causes seasons.  Where the sun’s rays strike Earth DIRECTLY, the season is SUMMER.  Where they strike Earth at the GREATEST SLANT, is WINTER.

5. Lesson 1 Continued (Day and Night)  Earth takes one year to revolve around the sun, but only one day to rotate.  As it rotates, the half of the Earth that is facing the sun has daytime.  The half of the Earth that is NOT facing the sun has nighttime.

6. Lesson 2 - How Do Earth and the Moon Interact?  Have you ever noticed the different shapes of the moon?  The different shapes we see are called MOON PHASES.  The moon does not really change. Just like Earth, half of the moon is always lit by the sun.  THE MOON REVOLVES AROUND THE EARTH.

7. Lesson 2 Continued  It takes the moon about 29 days to go through its phases in order.  This pattern of phases is called the LUNAR CYCLE.  When Earth blocks sunlight from reaching the moon, a LUNAR ECLIPSE happens.  When the moon’s shadow falls on Earth, a SOLAR ECLIPSE happens.

8. Lesson 3- What is the Solar System?  A PLANET is a large body of rock or gases.  Each planet revolves around the sun on its own path called an ORBIT.  The sun, planets, and other small things that orbit the sun make up the SOLAR SYSTEM.  The SUN, which is the biggest object in the solar system, is the CENTER of the solar system.

9. Lesson 3 Continued…  The sun is one of the biggest stars in the universe.  STARS are hot balls of glowing gases that give off energy.  The sun is the star closest to the Earth.  CONSTELLATIONS are groups of stars that appear to form shapes.

10. Lesson 3 Continued (Inner Planets)  The four planets closest to the sun are called the inner planets. Mercury Venus Earth Mars  All the inner planets have ROCKY SURFACES, are SMALLER THAN MOST OF THE OTHER PLANETS, and are WARMER THAN THE OTHER PLANETS.  **Earth and Mars have LENGTH OF DAYS that are close to the same time. Earth = 24 hours Mars = 25 hours

11. Lesson 3 Continued (Outer Planets)  The “five” planets farthest from the sun are called the outer planets. Jupiter Saturn Uranus Neptune “Pluto”  The outer planets are made MOSTLY OF FROZEN GASES, and most of them are VERY LARGE with MANY MOONS.