why do we have days and nights

What is a year? A Earth year is the time it takes the earth to make one orbit of the sun. How long does it take the Earth to orbit the Sun? The Earth\’s orbit around the Sun takes 365. 24 days. A \’day\’ is defined as the Earth spinning
once on its axis. An Earth year is 365. 24 days, or 8,765 hours, or 526,000 minutes, or 31. 6 million seconds. Why do we need to have one extra day each 4 years? calendar with the seasons of the year. If we didn\’t, then eventually, the months would flip around, and the northern hemisphere would have summer in January, and vice versa. The Earth takes approximately 365. 25 days to go around the Sun, yet our calendar year is 365 days. To fix this, we put on extra days in some years, called leap years.

Every 4 years, we have a leap year to add another day to the calendar to make up for the 4 missing quarters. In those leap years, a year lasts 366 days, and not the usual 365. The styrofoam ball represents the Earth. Draw the outlines of the continents on the styrofoam using a pencil. You will use the globe model (shown by your teacher) or the map of the globe on the projector as drawing guides. The drawing does not need to be detailed. Just make sure to draw the Philippines clearly. Include also Brazil which is on the opposite side of the Philippines. Color the drawn continents (land) green and the ocean (water) blue using the highlighters. Students must cooperate in drawing and coloring their own БEarth.

Б Carefully pierce the barbecue stick through the middle of the styrofoam ball. Use the marks as guide. The barbecue stick represents the line about which the Earth spins or rotates. This represents the Earth\’s axis of rotation. Take the two pieces of straws. Insert them over each end of the axis piercing the styrofoam ball. Make sure that they cover the barbecue stick entirely. Take the illustration board and investigate. The number written on it (degrees, symbolized as O) is a measure of the tilt of the Earth. Remember that the EarthБs axial tilt is 23. 5O degrees. Stick the two ends of the straw along this axis using the tape. Fold the flap to make the stand. The Earth should turn freely when you try to rotate it.

You are almost done. Put the Philippine flag in place and also the Brazil flag opposite it. The flags represent the two БextremeБ positions on Earth. Make the room completely dark. Using the flash light (representing the БSunБ), shine sunlight onto the Earth. The flashlight should not move. When light strikes the Philippine flag (day), take note that no light falls on Brazil (night). The Philippines is at Бnoon,Б the light shines directly on it. Then turn the globe eastward (from left to right) slowly until their positions reverse. Brazil now experiences daylight while Philippines experiences nighttime. As the БEarthБ moves, this pattern continues.