Day or night chart calculator

What the question means

The horizon in a birth chart is the line from the Ascendant to the Descendant. The upper half of the chart, houses 7 to 12, is above it; the lower half, houses 1 to 6, is below. Traditional astrologers call this division sect: a chart with the Sun above the horizon is a day chart, and one with the Sun below is a night chart. The Sun is called the luminary of sect in a day chart and the Moon in a night chart.

Why the clock and the place matter

Sunrise and sunset depend on the date and on where you were born, so a birth at 6 a.m. or 6 p.m. does not settle the question, and neither does your Sun sign. The calculation needs the actual local time and the coordinates of your birth city, converted with that place’s historical timezone. A time that was skipped or repeated by a local clock change is rejected rather than guessed.

Near the horizon

If the Sun is within half a degree of the Ascendant or Descendant, this page reports “On the horizon: not determined”. That half-degree buffer is a cautious product choice, not a measured clock error or a universal rule. Birth times are often rounded, and a few minutes can move the Sun across the horizon line in the chart.

What this one result can’t tell you

Day or night chart is a traditional label for one feature of a chart. It is not a mood, a sleep pattern, a health signal, a personality verdict, a good or bad rating or a prediction. This page does not score the other planets or rate the chart as a whole.

Method

Lunara calculates the Sun’s tropical, geocentric position with Swiss Ephemeris and your chart’s Placidus houses for the birth instant. Houses 7 to 12 count as day and houses 1 to 6 as night (the chart-horizon method). Placidus houses cannot be calculated for every time near the polar circles, so births above about 66° latitude are not supported. If the calculation cannot be completed, the page says so instead of estimating. Your birth details are used only for this calculation and are not stored.

Frequently asked questions

Can I use this without a birth time?

No. Whether the Sun was above or below the horizon depends on the exact time, so this page needs a recorded birth time and gives no result without one.

I was born at 7 a.m. Is that a day chart?

Not necessarily. Sunrise varies with the date and the place, and the chart’s horizon is calculated for your exact time and city. Enter your details to check.

What does “luminary of sect” mean?

It is a traditional term: the Sun in a day chart and the Moon in a night chart. On this page it is a label only, not a statement about your personality or wellbeing.

Why does another site show a different answer?

Usually because of a different birth time, a different timezone for the birth place, or a Sun very close to the horizon. If your result is “On the horizon”, a few minutes’ difference in the recorded time could change it.