In some older Western astrology traditions, a birth chart is called a day chart or a night chart. The name depends on where the Sun was relative to the local horizon at birth.
Look for the Sun and the horizon
If the Sun was above the horizon when you were born, astrologers call it a day chart. If the Sun was below the horizon, they call it a night chart. On a chart wheel, the line between the Ascendant and Descendant marks that horizon; check the Sun against the line, not just a house number.
Why older astrologers made the distinction
This day-or-night division is called sect. Traditional astrologers used it as one part of how they read planets in a chart. The label says nothing about whether a person is good, bad, outgoing, or quiet.
Birth time matters near sunrise and sunset
To place the horizon, a chart needs a birth time and place. If the Sun was close to rising or setting, a small error in the recorded time can change which side of the line it falls on. Leave the label open when the birth time is uncertain.
A few common questions
Does a night chart mean I am a night person?
No. It names where the Sun was relative to the local horizon at birth. It is not a description of your sleeping habits or character.
Sources & further reading
Astrology sources describe their own traditions and methods; they do not establish predictive accuracy. The writing exercises are original Lodestar editorial material.