Notes

TOPIC 1: PROOF THAT THE EARTH IS NOT FLAT
the following will prove to you the earth shape and that it is not flat.

AERIAL PHOTOGRAPH
Photographs that are taken of earth by satellites and astronauts from space show earth's curved shape and that it is spherical.

CIRCUM NAVIGATION
Man has travelled the earth using sea and air. This also proves that earth is not flat. Ships and airplanes wouldn't be able to go around the earth. it would have to stop.

SUNRISE and SUNSET
If the earth was flat every place on earth would experience sunrise at the same time. Since the earth is spherical it rotates from west to east. Persons in the west experience experiences night while in the east experience's day. Side that is facing the sun will get day and vice versa.
ECLIPSE OF THE MOON
An eclipse happens between the earth, sun and moon. When the earth passes between the sun and the moon it cuts the sun's light from the moon and the earth shadow is cast on the moon. the shadow that was cast on the moon is curved. this proves that earth has a curved surface.

CURVED HORIZON
When the earth's horizon is seen from heights and distances the horizon appears to be curved, if the earth was not spherical there would be no circular horizon.

TOPIC 2: EARTH'S ROTATION
What is Earth's rotation
the earth is tilted on an axis at an angle of 23 1/2 degrees.
the earth spins on its axis from west to east.
What is the result of earth rotation?
We have the day and night cycle because of it.
This causes different lengths of day and night as the earth completes an orbit around the sun each year.
only one half of the world can see the sun at any one time.
Day and night caused by the earth rotation if from west to east.
SAESONS AND HOW THEY ARE CAUSED.
1. the revolution of earth and the tilt of the axis results in
(i) changes in the length of day and night causes the seasons
(ii) The seasons- spring, summer, autumn and winter, each lasting three months. both poles (north and south) lean towards the sun alternate

Position of the overhead sun in relation to the earth
March 21st AT THE EQUATOR (0 degrees)
June 21st Tropic of Cancer (23 1/2 N)
September 23rd AT THE EQUATOR (0 degrees)
December 22nd Tropic of Capricorn (23 1/2 S)

1. These lines are also termed lines of latitude and they influence the seasons when the sun is in respective latitude.
2. At the tropics the seasons depend on rainfall and divided into:
(i) A dry season and (ii) a wet season
3. The convection rain belt follows the sun when the rain belt is not over head; there is a dry season.
June 21st- Sun is at the tropic of cancer.

1. The north pole is tilted towards the sun while the south pole is tilted away from the sun.
2. The summer is in the Northern Hemisphere.
3. Daylight is much longer than the nights. the longest and shortest day is called the solstices. in the summer solstice day is longer than nights and in the winter solstice it's vice versa.
4. June 21st is the longest day. It has shorter nights, and it is in the Northern Hemisphere.
5. All places within the Artic (66 1/2 degrees) receive 24 hours of sunlight as sunlight reached beyond 23 1/2 degrees. the Antarctic experiences the same thing except it receive 24 hours of darkness because the sun rays fall short.
6. The North Pole has 6 months of sunlight between March 21st and September 23rd and the south pole has the 6 months of darkness during the same time.
7. days and nights which are 12 hours long are called an equinox.

TOPIC 3: SOLAR ECLIPSE
An eclipse is a complete or partial hiding of the Sun and the earth cause by the moon passing in between the 2.
There are 2 types of solar eclipses:
1. Lunar eclipse (can occur 2-3 times a year, the moon phase is a full moon, and it happens for one hour)
2. Solar eclipse (can occur 2-5 times a year, the moon phase is a new moon, and it happens for 5-7 minutes)

SOLAR ECLIPSE
During a solar eclipse the sun is blocked by the moon. The moon moves between the sun and the earth casting a shadow on the earth that fully or partially blocks the sun's light in an area.
The following are the three types of solar eclipses.

TOTAL SOLAR ECLIPSE
1. the sun moon and earth are perfectly aligned.
2. this occurs when the moon completely covers the face of the sun.
3. the observers are now within the moon's umbra (This is the darkest part of the moon's shadow)

PARTIAL SOLAR ECLPISE
1. The sun, moon and earth are not perfectly lined up.
2. only a part of the sun appears to be covered giving it a crescent shape
3. it looks like the moon has taken a bite out of the sun
4. people outside the area covered by the moon's inner shadow ss a partial solar eclipse

ANNULAR SOLAR ECLIPSE
1. the moon passes between the sun and the earth when it is at or near its farthest point of earth.
2. it appears smaller than the sun and doesn't completely cover the sun
- it is unsafe to view a solar eclipse with the naked eye because the high intensity of the sun's light can damage the retina and even kill some of its cells.
- use eclipse glasses or solar viewers, pin hole projector, a telescope with solar filter and avoid prolonged exposures and don't use damage or scratched filters
- why scientist study solar eclipses are to 1. understanding the sun's corona and 2. studying earth's atmosphere
TOPIC 4: LUNAR ECLIPSE
During a lunar eclipse the moon moves into the earth's shadow causing the moon to be darkened
The following are the 3 types of solar eclipses.

TOTAL LUNAR ECLIPSE
1.the moon moves into the earth's umbra.
2. sunlight passing through earth's atmosphere reaches the moon's atmosphere lighting it dimly
NB: the more dust or clouds in Earth's atmosphere the redder the moon appears.

PARTIAL LUNAR ECLIPSE
1. This is an impart alignment in the sun, earth and moon.
2. This results in the moon passing through only part of Earth's umbra.
3. The shadow grows without entirely covering the moon.

PENUMBRAL ECLIPSE
1. The moon travels through the Earth's penumbra or faint outer part its shadow. the moon dims so slightly that it can be difficult to notice.