Candidate skies, not recovered eyewitness reports. No exact observation date is supplied by these passages. Patmos is used as Revelation’s literary location. Alexandria is a representative Egyptian observing site, not an established location for the authors of Pistis Sophia. The third-century examples were chosen by a declared astronomical rule.
Viewing time
Observing site
Local mean solar time · Julian
Sun altitude−6° · civil twilight
Above the local horizon
Look upward: north at top, east at left. The outer circle is the level horizon; the center is directly overhead. Stars are a sparse catalogue reference sample, not all stars or all 88 constellation outlines. Star marks are shown regardless of twilight brightness; a plotted mark does not guarantee visibility. Below-horizon planets appear in the table.
Babylon’s chamber overlay
A longitude diagram of the whole sky, including bodies below the horizon. Twelve equal 30° chambers are seasonal sectors, not irregular constellation borders. Positions include precession through Swiss Ephemeris transformations; this does not use the local Clock’s constant-period age labels.
| Body / letter | Chamber | Longitude | Altitude | Direction | Horizon geometry |
|---|
Measured planetary Gates at this viewing time
Five major longitude aspects, within the Clock’s default 3° tolerance. A Gate is the planetary-letter pair; the chamber tells us its setting. Angles refer to this dawn or dusk, which may be hours from the exact opposition.
Time uncertainty and the date of this candidate
Delta T converts Earth-rotation time (UT1) to ephemeris time (TT). Ancient Earth rotation is model-dependent. A nominal minute in the display is a calculation label, not minute-level historical certainty. The ±1,000-second perturbation below is a sensitivity example, not a statistical error bar.
Five third-century arrangements named in Pistis Sophia
Search interval: 200–350 CE inclusive. Daily brackets were searched for exact Venus–Jupiter longitude oppositions, then refined numerically. We retained the five sign-pair arrangements in chapters 139–140. There are 63 matches in this interval. For each arrangement the example nearest 1 January 275 CE is displayed; the midpoint is an analyst’s selection device, not a proposed composition date.
| Passage’s region | Exact longitude opposition · TT Julian | Gimel in | Peh in | Actual angular separation |
|---|
| Paraplex | 0279-10-28 21:28 | ה Hey | ל Lamed | 179.85° |
| Ariouth | 0270-12-08 05:26 | ח Chet | ע Ayin | 178.76° |
| Hekate | 0275-05-12 13:04 | נ Nun | ו Vav | 179.55° |
| Parhedron Typhon | 0276-07-17 10:49 | ס Samech | ז Zayin | 178.24° |
| Yachthanabas | 0278-08-19 10:19 | צ Tzadi | ט Tet | 179.83° |
Actual angular separation can differ from 180° because the bodies have different ecliptic latitudes. The passage specifies signs, not exact degrees, so these exact oppositions are one transparent subset of possible configurations.
The Revelation illustration
The Patmos example uses 95 CE, a plausible illustrative year in Revelation’s late-first-century context. We searched that year for dusk with the Sun within 15° longitude of Spica, the Moon 10°–40° east of the Sun and more than 5° above the horizon; we then chose the smallest Sun–Spica longitude difference. This produces the evening of 20 September 95 CE, proleptic Julian.
Spica supplies a star-based Virgo reference, distinct from the Yod seasonal sector. These filters are our exploratory reading, not criteria supplied by Revelation. The result does not establish an anatomical “Moon under Virgo’s feet,” twelve stars on a head, an identification of Draco with the dragon, or the date of John’s vision. Stars close to the Sun would be washed out even though their positions can be reconstructed.
How this helps the historical question
These views let us compare planetary arrangements, star positions, viewing geometry and Babylon’s interpretive vocabulary. A recurring sky pattern can establish a possible astronomical setting. Dating a text, demonstrating that an author observed a particular event, or tracing how an image changed between cultures still requires independent historical evidence.
Calculation method and reproducibility
Ephemeris: Swiss Ephemeris 2.10.03, explicit Moshier analytical mode. This differs from the earlier Babylon-reign DE441 reconstruction. Moshier is documented for 3000 BCE–3000 CE and needs no planetary data download. Source flags are checked to prevent silent mode changes.
All dates here use the proleptic Julian calendar. Root searches run in TT. Modeled UT1 uses Swiss Ephemeris Delta T. Dawn and dusk are the nearest crossings of Sun geometric altitude −6° to the selected event, so they can fall on different civil dates. Local mean solar time equals UT1 plus longitude/15 hours; it is not a modern time zone.
Planet positions for the horizon view are topocentric; the chamber wheel uses apparent geocentric tropical longitudes. Observer height is 0 m. The horizon is level and altitudes are geometric. Detection also depends on sky brightness, atmospheric extinction, weather and terrain, none of which are modeled. No claim is made that all marked stars could be seen at civil twilight.
The 65-star sample retains catalogue ICRS coordinates, proper motion, radial velocity and parallax; Swiss fixed-star routines propagate them to the selected epoch. It is irregularly selected from retrieved catalogue ranges, not a complete magnitude-limited survey. Traditional names are modern lookup labels; no ancient use of those names is implied.
BCE conventions for reuse: astronomical year 0 is 1 BCE and −1 is 2 BCE. All candidate dates in this particular search are CE. Gate angles and labels follow the inspected local Clock’s 0° / 60° / 90° / 120° / 180° scheme; its 180° aspect is called Revelation. That label is not evidence that the biblical book encodes the aspect.