EVERYDAY SCIENCE

Detailed explanation-1: -Due to the spherical shape of the earth, only half of it gets light from the sun at a time (Figure 3.2). The portion facing the sun experiences day while the other half away from the sun experiences night. The circle that divides the day from night on the globe is called the circle of illumination.

Detailed explanation-2: -Once every 24 hours Earth turns-or rotates on its axis-taking all of us with it. When we are on the side of Earth that is facing the Sun, we have daylight. As Earth continues its spin, we are moved to the side facing away from our Sun, and we have nighttime.

Detailed explanation-3: -The other half of the year, the Northern Hemisphere is tilted away from the Sun, creating winter in the north and summer in the south. Solstices happen twice per year, at the points in Earth’s orbit where this tilt is most pronounced.

Detailed explanation-4: -Around December 21, the Northern Hemisphere tilts the farthest away from the Sun. This is called the northern winter solstice, and it is when we have the least amount of daylight of any time of the year.

Detailed explanation-5: -One side of the Earth faces the sun, while the other side faces away into space. The side facing the sun is bathed in light and heat-we call this daytime. The side facing away is cooler and darker, and experiences night.