Motions of the Earth
Take a look around yourself
A fan or a top turns around a certain imaginary line. This line is called the axis of rotation.
Earth's Rotation
A circle drawn around the surface of the earth at a distance exactly halfway between north and south poles is called the equator.The equator divides earth in two equal parts Northern hemisphere and Southern hemisphere.
Day/night
Earth revolves around the sun. Rotates in anticlockwise motion moves from
west to east. The part that gets light has daytime The part that does not get light has night time.
Sunset and Sunrise Sometimes when we go for a trip we see places
called sunset or sunrise points from where these can be clearly seen on the horizon.
The sunrise point is in the East, sunset in West
Earth completes one revolution around the sun in 24 hours.- i.e. One Day Fix a point at any country.Rotate the earthFor approx. 12 hours that part of earth is towards the sun and approx. 12 hours away from sun.
12 hours daytime + 12 hours Night time = 24 hours
One year
Without changing it's Axis of rotation the earth revolves around the sun.
It takes365 days and 6 hours to complete one revolution around the sun.
Leap year
Every 4 year add 6 hours 6+6+6+6=24 hours-one day. According to Gregorian calendar the
month of February has 28 days. After every 4 years the lost one day makes the month of February of 29 days. So that Leap year has 366 day instead of 365 days.
Seasons Due to inclined axis of earth length of day
and night is not equal. 22 March to 23 sept. Northern Hemisphere-
Days are longer, so warmer, hence Summer season
In the same period in Southern hemisphere. Nights are longer, Less heat so itsWinter.
23 sept. to 22 March - Northern Hemisphere- Nights are longer Less heat - Winter.
In the same period southern hemisphere days are longer, More heat so its Summer.
In Bharat, 3 seasons
Summer : Vastant,Grishma, Chaitra, Vaishakh, Jeshta
Rainy : Varsh sharad Aashard shravan, bhadrapad
Winter : Hemant Shishir Ashwin, kartik, margshish
Why Moon small and
large
Earth revolves around the sun At the same time moon revolves around the
earth These two orbits intersects Sun moon and the earth are not always along a
straight line
Full moon
Moon has no light of its own We see moon because of sun's light that falls
on it. One day in a Month we see full moon
New Moon
One day in a Month we can not see any part of moon - No sun's light on the moon
From day of new moon it grows bigger and bigger.
Different shapes - Phrases.
Waxing moon and Wanning moon
From day of new moon to full moon it takes 14-15 day - Waxing moon Shukla
Full moon to new moon it takes - 14-15 day - wanning moon - krishna Paksha - 15 days.
Lunar Month -Tithi
15 day waxing moon + 15 day wanning = One month - Lunar Month
Everyday of Lunar month is Tithi.
Lets Summaries
The rotation of earth gives rise day & night Revolution of earth and inclination of axis
gives rise to cycle of seasons. Revolution of moon around earth gives rise
to phases of moon. Full moon to new moon - Waxing Shukla
paksha New moon to full moon - warming krishna
paksha