Ancient Egyptians predicted that the bright star in the sky was the beginning of the flood of the Nile River.
The imaginary line that runs through the north and south poles of the earth is the earth's axis.The north end of the axis points toward a point in space near the polaris which is the north star.The earth rotates about 1,600 kilometers per hour.
In addition to the rotation of the axis the earth travels around the sun.The movement of the earth around sun is called the revolution.
The ancient astronomers of Egypt counted the numbers of days between each first appearance of the star sirius.In this way they figured out that there were 365 days in a year.
Most places outside the tropics have four distinct seasons such as winter,spring,summer,fall.
Earth has seasons because the earth's axis is tilted as it moves around sun.
In June the earth's axis is pointing toward the sun,in December people who live Southern Hemisphere get the most direct sunlight.In March the sun is pointing northern hemisphere,In September the sun shines for more hours each day.
Moon motion around earth and on its axis
The Moon revolves around earth and rotates on it's own axis.it takes the moon about 27.3 days to revolve around the earth.
On a clear night the moon is full,but the moon does not produce the light it actually reflects off the sun.
During a new moon, the new moon is almost between earth and the sun, but most of the months the moon travels below or above the sun.A solar eclipse occurs when the moon passes between the earth and the sun.
During most of the months the moon goes near the earth's shadow but no into it.A lunar eclipse occurs on a full moon when earth is directly between the moon and the sun.
The force of the moon pulls the water towards it because the moon is close to the surface of the earth.
When the sun,earth and moon are nearly aline, the gravity of the sun and moon pull in the same direction which makes a spring tide.
The line between earth and sun is at right angle,to the line between earth and the moon,so when the sun pulls it's right angels to the moon it creates a neap tide.
Created with images by photovision - "ufo spaceship flying saucer" • jnissa - "paraanile_86" • jonathansautter - "star trails star rotation of the earth" • NASA Goddard Photo and Video - "Apollo 17, Earthrise over Moon" • humboldthead - "October Calender" • PublicDomainPictures - "road forest trees" • Kevin Krejci - "Earth Tilting Sideways" • sandid - "eclipses solar sun" • kasabubu - "lunar eclipse natural phenomenon of sky spectacle" • Ani Carrington - "High Tide" • Hans - "water blue shimmer" • pedrol - "NEAP TIDE by Peter Laws"