This ppt mainly focus on season in earth

1. SEASONS
• PREPARED BY BINDU.V

2. WHAT IS SEASON
THE SEASONS ARE THE RESULT OF THE MOVEMENT OF THE EARTH
AROUND THE SUN AND THE TILT OF THE EARTH’S AXIS. THE
EARTH’S ORBIT AROUND THE SUN IS AN ELLIPSE, SO SOME TIMES
DURING THE YEAR THE EARTH IS CLOSER TO THE SUN THAN AT
OTHER TIMES.

3. REVOLUTION
A REVOLUTION OCCURS AS THE EARTH MOVES AROUND THE SUN . TIME FOR
ONE REVOLUTION =365 ¼ DAYS (8,766 HOURS).THE SPEED OF EARTH’S
REVOLUTION IS ABOUT 18 MILES PER SECOND.

4. WHY WE HAVE SEASONS
• SEASONS ARE CAUSED BY THE
23.5° TILT OF EARTH COMBINED
WITH EARTH’S REVOLUTION
AROUND THE SUN
EARTH’S AXIS IS ALWAYS
POINTED IN THE SAME
DIRECTION (FIXED POSITION)

5. EARTH SEASONS

6. SEASONS ARE CLASSIFIED INTO 4
• EQUINOXES
• SUMMER SOLSTICE
• WINTER SOLSTICE

7. EQUINOXES
AS ASTRONOMICAL EVENT THAT HAPPENS TWICE , ONCE IN SPRING AND ONCE
IN AUTUMN IN EACH YEAR WHEN THE TILT OF THE EARTH’S AXIS IS INCLINED
NEITHER AWAY FROM NOR TOWARDS THE SUN.
DURING EQUINOXES THE TILT OF THE EARTH (RESPECT WITH THE SUN)
IS 0° BECAUSE OF IT DURATION OF DAY AND NIGHT ARE ALMOST EQUAL ON
THE EQUINOX DAY.
EQUINOX OCCURS ON 20TH OR 21ST MARCH OR 23RD SEPTEMBER IN EACH
YEAR AND BOTH DAYS HAS EQUAL LENGTH OF THE DAY AND NIGHT.

9. VERNAL EQUINOX
THE FIRST DAY OF THE SEASON OF THE SPRING ,AND THE BEGINNING OF A
LONG SUNLIGHT AT THE POLE. IN NORTHERN HEMISPHERE MARCH 20 (SUN
ACROSS EQUATOR AND MOVING NORTH WARDS. IN SOUTHERN HEMISPHERE
SEPTEMBER 22(SUN ACROSS EQUATOR AND MOVING SOUTH WARDS .
ON THE MARCH EQUINOX , IT’S SPRING TIME IN THE UK ,THE USA,
RUSSIA,CHINA, INDIA WHILE IT’S AUTUMN TIME IN AUSTRALIA, ARGENTINA,
CHILE…

10. AUTUMN EQUINOX
THE FIRST DAY OF THE SEASON OF AUTUMN, THE BEGINNING OF A LONG PERIOD OF
DARKNESS AT THE POLE. IN THE NORTHERN HEMISPHERE SEPTEMBER 22(SUN ACROSS THE
EQUATOR MOVING SOUTHWARD. IN THE SOUTHERN HEMISPHERE MARCH 22 (THE SUN
ACROSS THE NORTHWARD.

11. SUMMER SOLSTICE
• ON THIS DIAGRAM ,21ST JUNE THE
NORTHERN HEMISPHERE IS TILTED TOWARDS
THE SUN AND SUNRAYS DIRECTLY FALLS ON
THE TROPIC OF CANCER . AS A RESULT ,THIS
AREA RECEIVES MORE LIGHT AND HEAT. THE
DAY IS LONGEST AND NIGHT IS SHORTEST IN
NORTHERN HEMISPHERE. THIS PHENOMENON
IS KNOWN AS THE SUMMER SOLSTICE.
• SINCE THE LARGE PORTION OF NORTHERN
HEMISPHERE RECEIVES HEAT AND LIGHT
FROM SUN DURING THIS PERIOD . IT IS
SUMMER IN NORTHERN HEMISPHERE . THE
CONDITIONS ARE THE EXACT OPPOSITE IN
SOUTHERN HEMISPHERE AND IT EXPERIENCE

12. WINTER SOLSTICE
• ON THIS DIAGRAM ON 22 ND DECEMBER
,THE SOUTHERN HEMISPHERE IS TILTED
TOWARDS THE SUN AND SUNRAYS
DIRECTLY FALLS ON THE TROPIC OF
CAPRICORN . AS A RESULT OF
SOUTHERN HEMISPHERE RECEIVES MORE
LIGHT AND HEAT. THE DAY IS LONGEST
AND NIGHT IS SHORTEST IN SOUTHERN
HEMISPHERE AND THE REVERSE IS
HAPPENING IN NORTHERN HEMISPHERE.
THIS PHENOMENON IS KNOWN AS THE
WINTER SOLSTICE.
• SINCE A LARGE PORTION OF SOUTHERN
HEMISPHERE RE RECEIVES HEAT AND
LIGHT FROM SUN DURING THIS PERIOD,
IT IS SUMMER IN THE SOUTHERN

13. THANK YOU 🌎🌞