Epact Day Moon Lookup
Look up the Julian computus epact = 11 x (golden number - 1) mod 30, i.e. the conventional age in days of the mean moon on 1 January, displayed as 30 when the residue is zero.
Description
Look up the Julian computus epact = 11 x (golden number - 1) mod 30, i.e. the conventional age in days of the mean moon on 1 January, displayed as 30 when the residue is zero.
Epact Day Moon Lookup: Look up the Julian computus epact = 11 x (golden number - 1) mod 30, i.e. the conventional age in days of the mean moon on 1 January, displayed as 30 when the residue is zero.
When to use Epact Day Moon Lookup
Use this palaeographic utility to apply a stated dating, script, abbreviation, codicological, metrological, layout, or condition rule consistently while preparing manuscripts for scholarly review.
- Golden number
- Golden number of the year (from paleography/golden-number-cycle-position).
How Epact Day Moon Lookup works
Look up the Julian computus epact = 11 x (golden number - 1) mod 30, i.e. the conventional age in days of the mean moon on 1 January, displayed as 30 when the residue is zero. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.1
- Epact
- Epact value 0-29.
- Display form
- Liturgical display form; zero is written 30.
- Days to new moon
- Days until the next mean new moon under the same model.
Limitations and assumptions
- Script and manuscript evidence varies by language, region, institution, period, scribe, material, restoration, and cataloguing convention. A heuristic flag or score is not an authoritative date, hand attribution, reading, provenance, or conservation diagnosis.
- Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.
Alternative or Complementary approaches
Retain page images, scale, foliation, material, provenance, diplomatic transcription, uncertainty, and comparison exemplars; confirm conclusions with codicological context and specialist judgment.
References
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Chronology — Wikipedia contributors
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