Everyone's birth chart is divided in half by a horizontal line that's meant to represent the horizon. (Your rising, or ascendant sign can be found on the left, or eastern, end of this line.) We can derive a wide variety of insights from looking at which astrological houses and planets occupy the areas above and below the horizon, but for our purposes here you just have to check the position of one celestial body: the sun. If the sun is placed above the horizon on your chart, you likely identify with it more than you do your moon sign. If the sun appears below the horizon, however, there a chance that you see more of yourself in your moon sign. The former is known as a "day chart." The latter is, appropriately, called a "night chart."