+++
title = "大月"
description = "偉大な月、占星術時代または世界時代としても知られる、約 2,160 年の期間、歳差運動現象が黄道上の黄道帯を西に 30 度、つまり 12 度移動するのにかかる時間360度全周の。 12 の偉大な月は 1 つの偉大な年に相当します。"
template = "wiki-page.html"
toc = true

[extra]
redirect_to = { title = "World Age", path = "/wiki/world-age/" }
category = "Cosmic Chronology"
editorial_pass = "2026-05"
entry_type = "concept"
claim_type = "inferred"
alternative_names = ["Astrological age", "Precessional month", "World Age", "Aeon (in some Greek-derived usages)", "Platonic Month (in some Renaissance-tradition usages)"]

[extra.infobox]
type = "Unit of chronological measurement; one-twelfth of the precessional Great Year"
duration_modern = "Approximately 2,147.6 years (25,771.5 years ÷ 12, based on the modern astronomical precessional rate of ~50.29 arcseconds/year)"
duration_traditional = "Exactly 2,160 years (25,920 years ÷ 12, based on the astrological-tradition Great Year)"
component_units = "1 Great Month = 30° of ecliptic precession; 12 Great Months = 1 Great Year (full precessional cycle); 30 Great Days = 1 Great Month (where 1 Great Day = 72 years ≈ one human lifespan)"
zodiacal_correspondence = "Each Great Month corresponds to the period during which the vernal equinox point lies within one of the twelve zodiacal signs; the current Age is in transition between Pisces and Aquarius"
mathematical_properties = "The traditional figure 25,920 factors as 2⁶ × 3⁴ × 5 = 64 × 405 = 60 × 432 = 360 × 72; the Great Month figure 2,160 factors as 2⁴ × 3³ × 5; both numbers have substantial divisibility properties that account for their prominence in cross-cultural cosmological tradition"
cross_cultural_preservation = "The 25,920 / 2,160 / 432 numerical structure appears in Hindu *yuga* arithmetic (Kali Yuga = 432,000 years = 1/3 of the precessional Great Year measured in arcseconds), Babylonian sexagesimal numerology, the Platonic-tradition Magnus Annus, and other cross-cultural cosmological systems"
framework_significance = "Principal chronological unit for the corpus; the precessional Great Months provide the structured temporal framework within which the Elohim project and the broader prophetic record are dated"
+++

The **Great Month** is the unit of chronological measurement corresponding to **one-twelfth of the precessional Great Year** — the period required for the vernal equinox point to traverse 30° (one zodiacal sign) along the ecliptic at the precessional rate. The unit is also known as the **Astrological Age**, the **Precessional Month**, or the **World Age**, and constitutes the principal chronological building block on which the Wheel of Heaven corpus's broader temporal framework depends.

On the modern astronomical reckoning, the precessional Great Year completes one full cycle in approximately **25,771.5 years**, giving a Great Month of approximately **2,147.625 years** (≈ 2,147 years 7.5 months). On the astrological-tradition reckoning, the Great Year is taken as **25,920 years** exactly — a number with substantial divisibility properties (2⁶ × 3⁴ × 5 = 64 × 405 = 60 × 432 = 360 × 72) that makes it mathematically convenient and that has substantively shaped its prominence in cross-cultural cosmological tradition. On the traditional reckoning, the Great Month is exactly **2,160 years** (one-twelfth of 25,920), with the convenient factorization 2⁴ × 3³ × 5. The two reckonings differ by approximately 12 years per Great Month, sufficient to produce moderate divergence in long-period chronologies but small enough that the practical use of either figure produces broadly consistent results for the corpus's chronological purposes.

The corpus uses the Great Month as the principal chronological unit because the precessional Great Months align meaningfully with the substantive events of the broader prophetic record: the Adamite synthesis in the **Age of Leo** (c. 13,170 – 11,010 BCE), the Sumerian and Egyptian civilisations in the **Age of Taurus** (c. 6,690 – 4,530 BCE), the Hebrew prophetic period in the **Age of Aries** (c. 4,530 – 2,370 BCE on the broader reckoning, with the principal events concentrated in the middle-to-late portion), the Christian era in the **Age of Pisces** (c. 1 CE – 2,160 CE), and the contemporary transition into the **Age of Aquarius** (c. 2,160 CE onward). The framework's reading is that this alignment is not coincidental — that the Great Months structure the chronology of the Elohim project in a substantively meaningful way that is preserved in cross-cultural mythological tradition through the symbolic vocabulary of the zodiacal signs.

The Great Month entry is a focused unit-of-measurement entry within the broader Cosmic Chronology category. The astronomical phenomenon of precession itself is treated more fully in the dedicated [Precession](../precession/) entry; the broader cross-cultural doctrine of cosmic ages (the Hindu *yuga* cycle, the Hesiodic ages, the broader cyclical-cosmological tradition) is treated in the dedicated [World Age](../world-age/) entry; the full Great Year is treated in the dedicated [Great Year](../great-year/) entry. The present entry focuses specifically on the Great Month as a unit of time, its mathematical structure, the cross-cultural preservation of its numerical signatures, and the framework's specific use of the unit as chronological infrastructure.

## Duration and mathematical structure

The Great Month's duration depends on the choice of precessional rate. The two principal reckonings produce different numerical values, both of which are used in different contexts within the corpus's broader work.

### Modern astronomical reckoning

The contemporary astronomical measurement of the precessional rate is approximately **50.29 arcseconds per year** as measured in the contemporary epoch. This rate gives a full precessional cycle of approximately **25,771.5 years**:

$$
\begin{equation*}
\frac{360° \times 3600 \text{ arcsec/°}}{50.29 \text{ arcsec/year}} = \frac{1,296,000}{50.29} \approx 25,771.5 \text{ years}
\end{equation*}
$$

Dividing the modern precessional cycle by twelve gives the modern astronomical Great Month:

$$
\begin{equation*}
\frac{25,771.5 \text{ years}}{12} = 2,147.625 \text{ years}
\end{equation*}
$$

The modern astronomical Great Month is therefore approximately **2,147 years and 7.5 months**. This figure is the one used in contemporary scientific discussions of the precessional cycle and in the rigorous astronomical literature.

The precessional rate itself is not perfectly constant — it varies slowly across geological timescales due to the broader Earth-Moon system dynamics and the influence of the other planets. The contemporary rate is the value applicable to the present epoch; over substantially longer periods (millions of years), the rate varies by a few percent. For the corpus's chronological purposes — which span approximately one full precessional cycle from the Adamite synthesis (~13,000 BCE) through the contemporary period — the variation is negligible and the contemporary rate is adequate.

### Astrological-tradition reckoning

The astrological-tradition reckoning uses the convenient figure of **25,920 years** for the Great Year, giving a Great Month of exactly **2,160 years**:

$$
\begin{equation*}
\frac{25,920 \text{ years}}{12} = 2,160 \text{ years}
\end{equation*}
$$

The number 25,920 has substantial mathematical convenience that accounts for its traditional prominence:

$$
25,920 = 2^6 \times 3^4 \times 5 = 64 \times 405 = 60 \times 432 = 360 \times 72
$$

The number is divisible by:
- **360** (the number of degrees in a circle), giving 72 years per degree of ecliptic precession
- **60** (the base of Babylonian sexagesimal numeration), giving 432 years per sexagesimal unit
- **12** (the number of zodiacal signs), giving 2,160 years per sign — the Great Month
- **24** (the hours of the day or the doubled signs), giving 1,080 years per half-sign
- **36** (the decans of classical astrology), giving 720 years per decan
- **72** (the doubled half-sign, also the Great Day in the unit-system developed below)

The number 2,160 = 2⁴ × 3³ × 5 retains many of these divisibility properties:

$$
2,160 = 2^4 \times 3^3 \times 5 = 30 \times 72 = 12 \times 180 = 6 \times 360 = 60 \times 36
$$

The traditional reckoning's mathematical convenience accounts for its prominence in pre-modern cosmological systems. The corpus's broader work uses the traditional 25,920 / 2,160 figures as the primary reckoning while acknowledging the modern astronomical 25,771.5 / 2,147.6 figures as the contemporary empirical measurement. The choice between the two does not substantially affect the corpus's chronological framework — the difference of approximately 12 years per Great Month is well within the inherent uncertainty of the Age-boundary definitions.

### The Great Day

The Great Month admits further subdivision. If the Great Year is divided into 360 equal parts (corresponding to the 360 degrees of the ecliptic), each part is a **Great Day** of approximately 72 years on the traditional reckoning:

$$
\begin{equation*}
\frac{25,920 \text{ years}}{360} = 72 \text{ years}
\end{equation*}
$$

The Great Day corresponds to one degree of ecliptic precession. On the modern astronomical reckoning, the Great Day is approximately:

$$
\begin{equation*}
\frac{25,771.5 \text{ years}}{360} \approx 71.59 \text{ years}
\end{equation*}
$$

The corpus's adopted reckoning uses the round figure of 72 years for the Great Day. The Great Month accordingly contains 30 Great Days:

$$
\begin{equation*}
\frac{2,160 \text{ years}}{72 \text{ years}} = 30 \text{ Great Days}
\end{equation*}
$$

The system thus mirrors the structure of the ordinary year (12 months of approximately 30 days each), with the Great Year, Great Month, and Great Day standing in approximately the same proportional relationships as the ordinary year, month, and day.

### The 72-year Great Day and the human lifespan

A substantively interesting observation: the Great Day of 72 years approximates the **average human lifespan**. The contemporary global life expectancy at birth is approximately 73 years (2024 World Bank estimate, with substantial regional variation from approximately 53 years in some sub-Saharan African countries to approximately 84 years in Japan and several other developed countries). The biblical figure of "threescore years and ten" (Psalm 90:10) — the seventy-year span the Psalmist gives as the typical human lifetime — falls within two years of the Great Day. The Aristotelian and Hippocratic traditions used 70 years as the conventional human lifespan. The Roman tradition counted "septem decades" (seventy years) similarly.

The framework reads the 72-year Great Day / human-lifespan correspondence as substantively significant. The relationship suggests that:

- **One ordinary human life ≈ one Great Day of ecliptic precession** — a structural correspondence between human-scale time and cosmic-scale time
- **One Great Month (2,160 years) ≈ 30 human lifespans in succession** — roughly the temporal scope across which cultural-religious traditions maintain continuous transmission
- **One Great Year (25,920 years) ≈ 360 human lifespans** — substantially exceeding the temporal scope of any continuous cultural memory

The framework's broader reading treats this correspondence as one of several structural patterns connecting human and cosmic scales that the corpus engages. The dedicated [Anthropic principle](../anthropic-principle/) and related entries develop the broader pattern. The 72-year Great Day also connects to substantial source-tradition material on the number 72, developed in the framework section below.

## Cross-cultural preservation of the numerical structure

The numerical structure of the precessional cycle (25,920 years for the Great Year, 2,160 years for the Great Month, 72 years for the Great Day, and the broader family of related numbers including 432, 4,320, 43,200, and 432,000) is substantially preserved across multiple pre-modern cosmological traditions. The cross-cultural pattern is one of the principal substantive supports for the corpus's broader reading of pre-Hipparchian transmission of precessional content, developed more fully in the [Precession](../precession/) entry's treatment of the *Hamlet's Mill* thesis.

### The Hindu yuga cycle

The Hindu cosmological tradition preserves the most substantial numerical correspondences with the precessional cycle. The standard *yuga* periods (in human years, after the conversion factor of 360 human years per divine year is applied):

| Yuga | Duration in human years | Relationship to 432 |
|---|---|---|
| **Satya Yuga (Krita Yuga)** | 1,728,000 | 4 × 432,000 |
| **Treta Yuga** | 1,296,000 | 3 × 432,000 |
| **Dvapara Yuga** | 864,000 | 2 × 432,000 |
| **Kali Yuga** | 432,000 | 1 × 432,000 |
| **Mahayuga (sum of all four)** | 4,320,000 | 10 × 432,000 |
| **Kalpa (1,000 Mahayugas)** | 4,320,000,000 | 10,000 × 432,000 |

The number **432,000** is the basic unit of the entire Hindu cosmological time-system. The number relates to the precessional Great Year through several connections:

- **432,000 = 60 × 7,200 = 1,000 × 432**, with 432 as the basic unit
- The precessional Great Year of 25,920 years can be expressed as **432,000 ÷ 16.67** in arcsecond-related arithmetic
- More substantively: the Kali Yuga of 432,000 years corresponds (through symbolic-numerological calculation) to **one-third** of the precessional Great Year measured in arcseconds: the Great Year contains 360° × 60' × 60" = 1,296,000 arcseconds, of which 432,000 arcseconds = 120° = one-third
- The Mahayuga of 4,320,000 years can be read as the precessional Great Year (25,920) scaled by 10 × 360/2.16 = 1666.67, producing the 4,320,000 figure

The mainstream-academic reception of these numerical correspondences is contested. The earlier-20th-century scholarly tradition (particularly the work of Hermann Jacobi and others) treated the Hindu *yuga* numbers as substantially astronomical in derivation; subsequent scholarship has been more skeptical, treating the numbers as primarily cosmological-mythological with possible secondary astronomical connections. The framework's adopted position is that the substantive numerical correspondence between the Hindu cosmological time-system and the precessional cycle is sufficiently striking to warrant treating it as evidence of cross-cultural preservation of astronomical content — consistent with the broader *Hamlet's Mill* thesis.

A separate but related tradition is associated with **Sri Yukteshwar** (1855–1936), the Indian astronomer-astrologer whose *The Holy Science* (1894) proposed a 24,000-year *yuga* cycle (substantially shorter than the standard Puranic figure) explicitly correlated with the precessional cycle. The Yukteshwar tradition treats the standard 4.32-million-year *yuga* numbers as misinterpretations of an underlying 24,000-year cycle; the position is contested in the broader Hindu astronomical tradition and is treated as one possible reading rather than the orthodox position. The corpus's broader engagement with Hindu cosmology is treated in the [List of exegetic readings](../list-of-exegetic-readings/) entry.

### The Platonic Magnus Annus tradition

The Greek philosophical tradition includes substantial engagement with the concept of a cosmic "Great Year" predating Hipparchus's discovery of precession. **Plato**'s *Timaeus* (c. 360 BCE, Timaeus 39d) introduces the **Perfect Year** (*teleios eniautos*) or **Magnus Annus** (in the later Latin tradition) — the period required for all the celestial bodies (Sun, Moon, and the five visible planets) to return to their initial configuration:

> ...the perfect number of time brings to completion the perfect year at that moment when the relative speeds of all eight periods have been completed together and, measured by the circle of the Same that moves uniformly, have achieved their consummation.
>
> — Plato, *Timaeus* 39d (translation Cornford)

Plato did not specify the duration of the Perfect Year; later authors gave various figures. **Cicero** in *De Natura Deorum* (c. 45 BCE) discussed the concept following Plato. **Censorinus** (3rd century CE) preserved several ancient calculations: **Heraclitus** (c. 540–480 BCE) was given as 10,800 years; **Aristarchus of Samos** (c. 310–230 BCE) as 2,484 years; **Diogenes of Babylonia** as 360 times Heraclitus's figure. The figure of **36,000 years** for the Platonic Great Year appears in **Ptolemy** (c. 150 CE) and became the dominant Western figure through the medieval period.

The relationship between the Platonic Magnus Annus and the precessional Great Year is genuinely contested. Plato himself, predating Hipparchus by approximately 230 years, could not have known the precessional cycle. The original Magnus Annus concept appears to have been about planetary conjunctions rather than precession; the conflation of the two came after Hipparchus's discovery, when subsequent commentators retrospectively connected Plato's vague description to the newly identified precessional phenomenon. By the Renaissance, the Magnus Annus was commonly identified with the precessional cycle, and the figure of 25,920 years (sometimes 36,000) was used as the standard Platonic figure.

The framework's reading of the Magnus Annus tradition: the post-Hipparchian conflation of Plato's planetary-conjunction cycle with the precessional cycle was substantively *correct*, in the sense that the underlying intuition (a long cosmic cycle structuring history into ages) was applied to the actual phenomenon (precession) once that phenomenon was identified. The framework treats this as one instance of the broader pattern of pre-Hipparchian cosmic-cycle awareness being retrospectively connected to the precessional phenomenon.

### Babylonian sexagesimal numerology

The Babylonian astronomical tradition's sexagesimal (base-60) numeration produces several numerical correspondences with the precessional cycle:

- **The *sar* of 3,600 years** (60²) — a basic unit of long-period Babylonian chronology; 25,920 = 7.2 × 3,600
- **The *ner* of 600 years** (60 × 10) — 25,920 = 43.2 × 600
- **The *sussu* of 60 years** — 25,920 = 432 × 60
- **The 360-day year** (the standard Babylonian schematic year) — 25,920 = 72 × 360, with 72 as the Great Day

The Babylonian astronomical tradition did not explicitly identify precession (as discussed in the [Precession](../precession/) entry), but the numerical infrastructure of Babylonian astronomy substantially aligns with the precessional cycle. The framework reads this as evidence that the underlying numerical structure was preserved in the Babylonian tradition through symbolic-numerological transmission, even if the explicit astronomical identification of precession was not present.

### The Mesoamerican Long Count

The Mesoamerican Long Count calendar (developed by the Olmec and Maya civilisations) uses a base-20 (vigesimal) system with some base-18 modifications. The principal Long Count units:

- **K'in** = 1 day
- **Winal** = 20 k'in = 20 days
- **Tun** = 18 winal = 360 days (note the base-18 modification, producing a 360-day "year" comparable to the Babylonian schematic year)
- **K'atun** = 20 tun = 7,200 days ≈ 19.7 years
- **B'ak'tun** = 20 k'atun = 144,000 days ≈ 394.3 years
- **Great Cycle (13 B'ak'tun)** = 1,872,000 days ≈ 5,125 years

The relationship between the Long Count and the precessional cycle is substantively contested. The widely-publicised "2012 phenomenon" — the completion of the 13 B'ak'tun Great Cycle on December 21, 2012 — was interpreted by some commentators as indicating Mayan awareness of the precessional cycle (with one Great Cycle corresponding to approximately one-fifth of the precessional period, or with the December solstice 2012 alignment to the galactic centre being a precession-related event). The mainstream-academic position is that the Long Count is principally a counting system without explicit precessional content; the contemporary popular conflation of the Long Count with precession is largely a 20th-21st century interpretive overlay rather than an established Mayan tradition.

The framework's adopted position: the Mesoamerican Long Count's substantive numerical correspondences with the precessional cycle (the 360-day Tun base, the relationship between the K'atun and the Great Day, the broader integration of cosmic time-structure into the calendar system) are consistent with the cross-cultural pattern that the framework reads as evidence of pre-Hipparchian astronomical transmission. The specific question of whether the Long Count explicitly encodes precession is treated as open.

### The broader cross-cultural pattern

The combined evidence from the Hindu, Greek, Babylonian, and Mesoamerican traditions supports the framework's reading that the precessional Great Year and Great Month numerical structures were preserved across multiple pre-modern cosmological systems. The specific numbers (25,920, 2,160, 432, 72, 360, 4,320) appear with substantial frequency in cosmological-mythological contexts that predate explicit astronomical identification of precession. The framework's reading is that this pattern is evidence of cross-cultural transmission of astronomical content through symbolic-numerological vocabulary — the broader thesis developed in **Giorgio de Santillana and Hertha von Dechend's *Hamlet's Mill: An Essay on Myth and the Frame of Time*** (1969), treated in more detail in the [Precession](../precession/) entry.

## In the Wheel of Heaven framework

The framework's specific use of the Great Month is multilayered. The unit serves as chronological infrastructure for the corpus's broader work, and the substantive symbolic-numerological properties of the unit and its components connect to substantial source-tradition material.

### Great Months as chronological infrastructure

The corpus's broader interpretive work uses Great Months as the structured temporal framework for dating the principal events of the Elohim project and the broader prophetic record. The principal Great Month identifications used across the corpus:

- **Age of Virgo** (c. 15,330 – 13,170 BCE) — the *yom* 5 phase of Genesis 1, the synthesis of the broader animal life
- **Age of Leo** (c. 13,170 – 11,010 BCE) — the *yom* 6 human-synthesis phase, the principal Adamite synthesis, the Eden phase
- **Age of Cancer** (c. 11,010 – 8,850 BCE) — the post-deluge reorganisation following the Younger Dryas-era catastrophic events
- **Age of Gemini** (c. 8,850 – 6,690 BCE) — the early Neolithic population developments, the broader Holocene climate stabilisation
- **Age of Taurus** (c. 6,690 – 4,530 BCE) — the Sumerian, Egyptian, and broader Bronze Age civilisations
- **Age of Aries** (c. 4,530 – 2,370 BCE) — the principal Hebrew prophetic period (Abraham through Moses, the Sinai theophany, the Davidic monarchy, the prophetic tradition)
- **Age of Pisces** (c. 1 CE – 2,160 CE) — the Christian era and the broader subsequent religious developments
- **Age of Aquarius** (c. 2,160 CE onward) — the contemporary recovery period, overlapping with the corpus's identification of the **Age of Apocalypse**

The dedicated entries on each Great Month develop the specific content; the present entry establishes the chronological unit on which the broader framework depends.

### The chronological precision question

The framework's adopted reckoning produces Great Month boundary dates with approximately ±200-year uncertainty due to several methodological choices:

- **Which precessional rate to use** — the modern astronomical 25,771.5-year cycle vs. the traditional 25,920-year cycle produces approximately 12 years of difference per Great Month, accumulating to approximately 150 years across the full cycle
- **Which starting reference to use** — the choice of starting reference (the contemporary equinox position, the position at a specific historical date, the conventional zero-point at 0° Aries in the tropical zodiac, etc.) produces variation in the boundary dates
- **How to define constellation boundaries** — the IAU-standardised constellation boundaries (defined 1930) differ substantially from the classical astrological boundaries, producing alternative dating systems

The framework's adopted reckoning uses the traditional 25,920-year cycle and the conventional zero-point at the vernal equinox / 0° Aries in the tropical zodiac. The boundary dates given above should be treated as approximate (±200 years), with the substantive interpretive content concerning the Great Month-specific events and not the precise transition dates.

### The Great Day and the prophetic generations

The framework reads the 72-year Great Day as substantively connected to the broader pattern of prophetic transmission. The principal observations:

- **One Great Day (72 years) ≈ one human lifespan** — the temporal scope across which a single prophetic figure can directly transmit content
- **One Great Day ≈ three biblical generations** — the standard biblical generation of approximately 20-25 years (Genesis 25:26: Isaac at age 60 when Jacob was born; Genesis 5 genealogies' approximately 20-year average childbearing ages on the framework's reading)
- **Thirty Great Days = one Great Month** — the temporal scope across which a religious tradition's continuous transmission typically operates before substantial reformulation or renewal

The framework's broader reading treats the structural relationship between the 72-year Great Day and the typical prophetic lifespan as preserving content about the chronological infrastructure within which the prophetic tradition operates. The dedicated [List of prophets and religions](../list-of-prophets-and-religions/) entry develops the broader pattern; the present entry establishes the chronological-unit connection.

### The symbolic-numerological significance of 72

The number 72 — the Great Day in years — has substantial significance across multiple source-tradition contexts that the framework's broader work engages:

- **The 72 disciples of Luke 10:1** — the secondary group of disciples sent out by Jesus, distinguished from the principal twelve. The number 72 in some manuscript traditions; 70 in others (the textual variant is well-attested and longstanding). The framework reads the 72/70 variation as reflecting the underlying symbolic-numerological pattern.
- **The 70 (or 72) nations of the Table of Nations** — Genesis 10's enumeration of the post-deluge nations descended from Noah's three sons. The Masoretic Hebrew text gives 70; the Septuagint Greek translation gives 72. The same 70/72 variation pattern appears here as in Luke 10:1, consistent with a shared underlying symbolic structure.
- **The 70 elders of Israel** — Numbers 11:16-25, the seventy elders given a portion of Moses's spirit at the Tabernacle. The number connects to the broader pattern of 70/72 as a representative-completion number in the Hebrew tradition.
- **The 72 names of God in Kabbalah** — the *Shemhamphorash*, the 72-letter Name of God derived from Exodus 14:19-21 (each verse containing 72 Hebrew letters; combined, they produce a 72 × 3 = 216 letter sequence that is divided into 72 three-letter Names). The Kabbalistic tradition is substantially developed in *Sefer Yetzirah* (c. 200-900 CE) and subsequent medieval Jewish mystical literature.
- **The 72 angels of the *Shemhamphorash*** — derived from the 72 Names, each Name associated with a specific angel. The tradition is developed in Pseudo-Solomonic and broader medieval ceremonial magic literature.
- **The 70 (or 72) translators of the Septuagint** — the legendary group of Jewish scholars who translated the Hebrew Bible into Greek under Ptolemy II Philadelphus (mid-3rd century BCE). The number is traditional 70 in earlier sources, 72 in later (six translators from each of the twelve tribes).
- **The 72 conspirators against Osiris** — in the Egyptian myth of Osiris's death at the hands of Set and his seventy-two co-conspirators (preserved in Plutarch's *De Iside et Osiride*, c. 100 CE). The number 72 in this context has been read by some interpreters (including Santillana and von Dechend) as connecting to the precessional Great Day.
- **The 72-day Egyptian decan-week period** — in the broader Egyptian astronomical tradition, 72 days corresponds to one-fifth of the 360-day schematic year and connects to the decanal division of the ecliptic.
- **The 72-fold structure of the *Bardo Thodol* (Tibetan Book of the Dead)** — the 72 manifestations of the deities encountered in the bardo state, developed in the Tibetan Buddhist tradition.

The cross-cultural appearance of the number 72 in symbolic-numerological contexts is consistent with the framework's broader reading that pre-modern cosmological systems preserved the precessional numerical structure through symbolic vocabulary. The framework does not require that every appearance of 72 in source-tradition material be precessionally significant — the number has substantial intrinsic mathematical properties (the divisibility, the close approximation to human lifespan, etc.) that account for some of its prominence. But the broader pattern is consistent with the *Hamlet's Mill* thesis.

### Connection to the source-tradition chronological content

The framework's broader reading uses the Great Month framework to interpret several specific source-tradition chronological passages:

- **The Genesis 5 antediluvian genealogy** — the long-lived patriarchs (Methuselah at 969 years, the others at comparably long ages) preserve content that the framework reads through the Great Day pattern: the 900-1,000 year lifespans approximate **12-14 Great Days** (12 × 72 = 864 years; 14 × 72 = 1,008 years), suggesting that the antediluvian lifespans may preserve content about a different chronological relationship between human and cosmic scales in the immediate post-synthesis Adamite population.
- **The 70-year span of Psalm 90:10** — "the years of our life are seventy" — connects directly to the standard 70-year human lifespan that approximates the 72-year Great Day
- **The 70 years of the Babylonian exile (Jeremiah 25:11-12; 29:10)** — the standard biblical figure for the duration of the exile, again approximating the 72-year Great Day
- **The "year of years" or jubilee pattern** — the 49-year (7 × 7) jubilee cycle of Leviticus 25, while not directly precessional, reflects the broader pattern of structured time-cycles in the biblical chronological vocabulary

The framework's reading is that the source-tradition chronological vocabulary substantially incorporates the broader precessional numerical structure — both directly (through the 72-year Great Day approximating the prophetic lifespan and the 2,160-year Great Month framing the major religious-historical periods) and indirectly (through the broader cross-cultural symbolic-numerological vocabulary of 72, 360, 432, and related numbers).

## Connections to the broader framework

The Great Month entry connects to several specific corpus entries.

**The Precession entry.** The dedicated [Precession](../precession/) entry treats the astronomical phenomenon itself; the Great Month is the principal chronological unit derived from precession.

**The Great Year entry.** The dedicated [Great Year](../great-year/) entry treats the full precessional cycle (12 Great Months); the Great Month is its principal subdivision.

**The World Age entry.** The dedicated [World Age](../world-age/) entry treats the broader cross-cultural doctrine of cosmic ages; the Great Month is one specific articulation of this broader doctrine.

**The individual Age entries.** The dedicated entries on each Great Month — [Age of Virgo](../timeline/age-of-virgo/), [Age of Leo](../timeline/age-of-leo/), [Age of Cancer](../timeline/age-of-cancer/), [Age of Gemini](../timeline/age-of-gemini/), [Age of Taurus](../timeline/age-of-taurus/), [Age of Aries](../timeline/age-of-aries/), [Age of Pisces](../timeline/age-of-pisces/), [Age of Aquarius](../timeline/age-of-aquarius/), and the [Age of Apocalypse](../age-of-apocalypse/) — develop the specific content of each Great Month within the framework that the present entry establishes.

**The Genesis entry.** The dedicated [Genesis](../genesis/) entry treats the *yamim* sequence as structured by the precessional Great Months (each *yom* corresponding to a specific Age on the framework's reading).

**The List of mythemes and mythological motifs entry.** The dedicated [List of mythemes and mythological motifs](../list-of-mythemes-and-mythological-motifs/) entry treats the broader cross-cultural mythological preservation of astronomical content, including the numerical patterns developed in the present entry.

**The List of exegetic readings entry.** The dedicated [List of exegetic readings](../list-of-exegetic-readings/) entry treats the broader interpretive tradition that the framework engages, including the Hindu *yuga* and broader cosmological-cycle readings.

## Open questions

The Great Month entry surfaces several open questions for the framework's broader interpretive work.

- **The reconciliation of the modern astronomical and traditional reckonings.** The framework currently uses both the modern astronomical 25,771.5-year cycle and the traditional 25,920-year cycle in different contexts. Whether the corpus should converge on one of these as the principal reckoning, and what the principled basis for the choice should be, is treated as open.
- **The specific significance of 432.** The number 432 appears with extraordinary frequency in cross-cultural cosmological-numerological contexts (the Hindu 432,000-year Kali Yuga, the 4,320,000-year Mahayuga, the 432,000-year Babylonian *sar*-related calculations, the 432 Hz frequency in some musical-tradition contexts). Whether the 432 pattern is principally a derivation from the precessional structure (with 432 = 60 × 7.2, where 7.2 is the close approximation to 72/10) or whether 432 has independent significance that secondarily connects to precession is treated as open.
- **The Yukteshwar 24,000-year cycle.** The 19th-century Indian astrological tradition associated with Sri Yukteshwar uses a 24,000-year *yuga* cycle that does not match the standard Puranic figures. The framework's adopted position is open on whether the Yukteshwar reading preserves substantive earlier content or is a 19th-century reinterpretation; subsequent corpus work on the broader Hindu cosmological tradition may permit more developed readings.
- **The Egyptian decanal connection.** The Egyptian astronomical tradition's 36 decans (10° divisions of the ecliptic, corresponding to 10-day periods within the 360-day schematic year) and the broader 72-day Egyptian periods may preserve precessional content. Future corpus work on the Egyptian astronomical tradition may permit more developed readings.
- **The specific operational use by the Elohim.** Whether the Elohim used the Great Month / Great Year cycle as navigation infrastructure (per the Biglino reading developed in the [Precession](../precession/) entry), as project-chronology infrastructure, as some other operational application, or as a combination of these is treated as open.

## See also

- [Precession](../precession/)
- [Great Year](../great-year/)
- [World Age](../world-age/)
- [Age of Virgo](../timeline/age-of-virgo/)
- [Age of Leo](../timeline/age-of-leo/)
- [Age of Cancer](../timeline/age-of-cancer/)
- [Age of Gemini](../timeline/age-of-gemini/)
- [Age of Taurus](../timeline/age-of-taurus/)
- [Age of Aries](../timeline/age-of-aries/)
- [Age of Pisces](../timeline/age-of-pisces/)
- [Age of Aquarius](../timeline/age-of-aquarius/)
- [Age of Apocalypse](../age-of-apocalypse/)
- [Genesis](../genesis/)
- [List of mythemes and mythological motifs](../list-of-mythemes-and-mythological-motifs/)
- [List of exegetic readings](../list-of-exegetic-readings/)
- [List of prophets and religions](../list-of-prophets-and-religions/)

## External links

- [Astrological age | Wikipedia](https://en.wikipedia.org/wiki/Astrological_age)
- [Great Year | Wikipedia](https://en.wikipedia.org/wiki/Great_Year)
- [Yuga | Wikipedia](https://en.wikipedia.org/wiki/Yuga)
- [Plato, *Timaeus* | Perseus Digital Library](http://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.01.0179)

## References

Vorilhon, Claude (Raël). *Le Livre qui dit la vérité* (1974) and *Les extra-terrestres m'ont emmené sur leur planète* (1976), collected as *Message from the Designers* (Raëlian Foundation, current English edition). [Primary source for the framework's broader interpretive work; the Great Month chronological framework is not explicitly developed in the Vorilhon source material but is consistent with the broader corpus position.]

Santillana, Giorgio de, and Hertha von Dechend. *Hamlet's Mill: An Essay on Myth and the Frame of Time*. Boston: Gambit, 1969. [The foundational scholarly engagement with the cross-cultural preservation of precessional numerical content, treating the 25,920 / 432 / 72 / 360 numerical structure as evidence of pre-Hipparchian transmission.]

Plato. *Timaeus*. c. 360 BCE. Standard English translation: *Plato: Complete Works*, edited by John M. Cooper. Hackett, 1997. [The foundational philosophical source for the Magnus Annus / Great Year concept that was subsequently identified with the precessional cycle.]

Cicero. *De Natura Deorum*. c. 45 BCE. [The principal Latin source for the post-Platonic Magnus Annus tradition.]

Censorinus. *De Die Natali*. c. 238 CE. [Preserves the various ancient calculations of the Great Year (Heraclitus, Aristarchus, Diogenes of Babylonia).]

Plutarch. *De Iside et Osiride* (*On Isis and Osiris*). c. 100 CE. [Preserves the Egyptian Osiris-Set tradition with the 72 conspirators against Osiris.]

Biglino, Mauro. *Il libro che cambierà per sempre le nostre idee sulla Bibbia*. Mondadori, 2011. [The contemporary philological reading of the Hebrew Bible's chronological content, including the 70/72 numerical patterns.]

Biglino, Mauro, and Giorgio Cattaneo. *The Naked Bible: The Truth About the Most Famous Book in History*. 2022.

Yukteshwar Giri, Swami Sri. *The Holy Science (Kaivalya Darsanam)*. Yogoda Satsanga Society of India, 1894. [The principal Indian astrological-spiritual tradition treating the *yuga* cycle as a 24,000-year precessional cycle.]

Cruttenden, Walter. *Lost Star of Myth and Time*. St. Lynn's Press, 2006. [Contemporary popular treatment of the broader cross-cultural Great Year tradition.]

Sellers, Jane B. *The Death of Gods in Ancient Egypt: An Essay on Egyptian Religion and the Frame of Time*. Lulu, 2007 (expanded edition). [Contemporary scholarly engagement with the Egyptian astronomical tradition and its preservation of precessional content.]

Sendy, Jean. *La Lune, clé de la Bible*. Julliard, 1968.

Sendy, Jean. *Ces dieux qui firent le ciel et la terre*. Robert Laffont, 1969.

Hancock, Graham. *Fingerprints of the Gods: The Evidence of Earth's Lost Civilization*. Crown, 1995. [The principal popular treatment of the broader cross-cultural precessional-numerical pattern.]

Evans, James. *The History and Practice of Ancient Astronomy*. Oxford University Press, 1998.

Neugebauer, Otto. *A History of Ancient Mathematical Astronomy*. 3 vols. Springer-Verlag, 1975.

Pingree, David. "Astronomy and Astrology in India and Iran." *Isis* 54, no. 2 (1963): 229–246. [The principal academic treatment of the relationship between Indian and Iranian astronomical traditions, including the *yuga* cycle.]

Hartner, Willy. "The Earliest History of the Constellations in the Near East and the Motif of the Lion-Bull Combat." *Journal of Near Eastern Studies* 24, no. 1/2 (1965): 1–16.

"Astrological age." *Wikipedia*. <https://en.wikipedia.org/wiki/Astrological_age>

"Great Year." *Wikipedia*. <https://en.wikipedia.org/wiki/Great_Year>

"Yuga." *Wikipedia*. <https://en.wikipedia.org/wiki/Yuga>

"Kalpa (time)." *Wikipedia*. <https://en.wikipedia.org/wiki/Kalpa_(time)>

"Long Count calendar." *Wikipedia*. <https://en.wikipedia.org/wiki/Mesoamerican_Long_Count_calendar>