Astronomy 1021 Chapter Notes - Chapter 2.2: March Equinox, September Equinox, Northern Hemisphere

• School: Western University
• Department: Astronomy
• Course: Astronomy 1021
• Professor: Margaret Campbell- Brown

Document Summary

What causes the seasons? the tilt of the earth"s axis causes the sunlight to fall differently on earth at different times of year. The orientation of the axis relative to the sun changes over the course of each orbit. The two hemispheres are alternatively tipped toward and away from the sun, which is why the experience the opposite seasons. A steeper angle means more concentrated sunlight, which tends to make it warmer. This steeper angle means the ecliptic of the sun is higher, thus giving longer hours of sunlight. Both hemispheres are illuminated equally in march and september. The changes in season are only caused by a change in the tilt of the axis, and have nothing to do with the distance of earth from the sun. The june or summer solstice occurs around june 21 and is the moment when the northern. Hemisphere is tipped most directly towards the sun and receives the most daylight.