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Astral Atlas
Wiki concept · Named stars

Sirius

Also called Alpha Canis Majoris · Dog Star

The IAU-recognised proper name for Alpha Canis Majoris A, the bright star in Canis Major used here as a selectable astronomical target.

In this entry

Astronomical identity

Sirius is the IAU proper name assigned to Alpha Canis Majoris A (HR 2491), in Canis Major. The IAU naming table lists it as a component A; that distinction matters where a catalogue resolves a stellar system rather than a folklore label.

For an angular-event tool, the reproducible object is the selected catalogue target and its position model at the stated time and place. ‘Fixed’ does not waive the need to name epoch, coordinate frame, proper motion, or horizon convention.

IAU: Naming Stars ↗

Name and historical record

LSJ gives Greek seirios as the dog-star and ‘the scorcher’. The IAU notes Sirius among the few names retained from Greek antiquity, with an appearance in Hesiod but not the Almagest.

A heat-associated ancient name is a historical/literary datum. It should not be turned into a physical property of a local rise or into a personal prediction.

LSJ: σείριος ↗IAU: Naming Stars ↗

Ptolemy’s named comparison

In Tetrabiblos I.9, Ptolemy calls the bright star in the mouth of Canis like Jupiter and, to a lesser degree, Mars. This is the directly evidenced comparative label carried by the companion historical dataset.

It is neither a zodiacal conjunction rule nor a modern angular-event recipe. Ptolemy closes the chapter by calling these observations of predecessors.

Ptolemy, Tetrabiblos I.9 ↗

Use in a modern paran result

Start with the event row: for example, record ‘Sirius rising’ alongside the other body’s named angle, the full local timestamps, the separation, location, and tolerance. Compare a second location only after retaining those same settings.

Brady describes modern parans as simultaneous contact with earth-generated angles and a blending of star and planet meanings. If the optional Ptolemaic lens is enabled, place its Jupiter/lesser-Mars comparison beside the event facts; any visitor question remains original reflection.

Bernadette Brady, Fixed Stars, other voices in our astrology ↗

Word origin · etymology

Ancient Greek Seirios.

LSJ records seirios as the dog-star and ‘the scorcher’; the name’s older derivation is not settled here.

LSJ: σείριος ↗

How we know · epistemology

Astronomical identification; historical and interpretive records kept separate.

The catalogue models the direction of the named Sirius target; a component name does not imply that the event solver models its binary orbit. The Greek name and Ptolemaic comparison are historical records, not measured personal effects.

IAU: Naming Stars ↗Ptolemy, Tetrabiblos I.9 ↗

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Terms used in this explanation

These links connect subjects and terminology. They do not establish a shared historical origin.

Sources & provenance

Use the citations beside each section to distinguish a calculation convention, a historical teaching and an editorial example.

Find these sources across the wiki →

  1. IAU: Naming Stars ↗
  2. LSJ: σείριος ↗
  3. Ptolemy, Tetrabiblos I.9 ↗
  4. Bernadette Brady, Fixed Stars, other voices in our astrology ↗