View all 24 planetary hours (horas) for any date and location. The first hora at sunrise is ruled by the weekday's planetary lord; each subsequent hora steps through the classical Chaldean sequence. The currently active hora is highlighted.
How planetary hours are computed
The day is divided into 12 equal horas (sunrise to sunset) and 12 night horas (sunset to next sunrise). The lord of the first hora at sunrise is determined by the weekday — Sunday by the Sun, Monday by the Moon and so on through the Chaldean order. Each successive hora advances through the fixed cycle: Sun, Venus, Mercury, Moon, Saturn, Jupiter, Mars. One mathematical invariant confirms the cycle is correct: the 25th hora (the first of the next day) must match the next weekday's planetary lord. Night horas use an approximated next-sunrise (sunrise + 24 hours); the difference is generally under a few minutes.
Frequently asked questions
What is a Hora (planetary hour)?
A hora is one of 24 planetary hours in a day — 12 for daytime (sunrise to sunset) and 12 for night (sunset to next sunrise). Each hora is ruled by one of the seven classical planets: Sun, Moon, Mars, Mercury, Jupiter, Venus and Saturn. In Vedic and classical Western astrology, activities initiated during a planet's hora are thought to carry that planet's qualities.
Which planet rules the first hora of each day?
The first hora at sunrise is ruled by the planet associated with that weekday: Sunday by the Sun, Monday by the Moon, Tuesday by Mars, Wednesday by Mercury, Thursday by Jupiter, Friday by Venus and Saturday by Saturn. This is also why the days carry those planets' names.
How does the hora sequence advance?
After the first hora, the rulership advances through the cycle Sun → Venus → Mercury → Moon → Saturn → Jupiter → Mars → Sun … and so on. This cycle does not follow weekday order — it follows the traditional "Chaldean order" of the planets by apparent speed.
Are day and night horas the same length?
No. Day horas are each one-twelfth of the daylight span (sunrise to sunset). Night horas are each one-twelfth of the night span (sunset to the next sunrise). On an equinox day both are exactly 60 minutes; otherwise they vary with the season.
Why does this tool use an approximation for night horas?
Night horas technically end at the next day's sunrise. To keep the calculation local (one API call), this tool approximates next sunrise as exactly 24 hours after today's sunrise. The difference is typically a few seconds to a couple of minutes.
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