lesson 1 the solar system
LESSON 2: THE EARTH
It is the 3rd planet of the solar system it is the only planet that support live.
WHY?? Bcs of the presence of free existing water
- A. Size of the earth.
The total surface area is estimated to be 510100779km². The diameter and the circumference of the earth are different at the poles and at the equator. It is larger at the equator and reduces toward the poles these dimension are as follows
| Point | Diameter | Circumference |
| Equator | 12682 | 40085 |
| Poles | 12639 | 39955 |
- B. The shape
The earth has a form that looks like on arrange. It is slightly flattened at the top and button ends. This ends are called POLES. The spherical shape of the earth is called GEOID
- C. Proofs or evidence for the spherical shape
- Ship visibility: A person standing at the cost looking ship seas the top (mast) of the ship before where body of the ship before where body of the ship (hull). If the earth was flat, the whole ship will be seen at once and will disappear at once.
- Circum Navigation of the earth: People who have travelled round the world in the same direction finally come back to their starting point if the earth was flat they would have come back to the same point.
- Aerial photography: These are picture at great height above the atmosphere and in space. All pictures show that the earth is having a spherical shape. This is the most convincing group
- Sun rise and Sun set: The earth’s movement from the east to west had made places in the east to see sun and at the same time people in the west will see darkness
- Eclipse of the moon: It is when the earth come between the sun and the moon during this period, the shadow of the earth thrown on the moon is round. If the earth was flat its shadow on the moon will be a square
