celestial epoch

• CURIE: gmeow:celestialEpoch
• IRI: https://blackcatinformatics.ca/gmeow/celestialEpoch
• Category: property
• Defined by: gmeow:slices/places
• Box roles: RBox role (What is this?)

The epoch (Julian year, e.g. 2000.0) for which the coordinates are expressed. Required for proper-motion propagation; frame-relative per Principle 11.

Structure

Property shape: datatype property; gmeow:CelestialCoordinates -> xsd:decimal

Practical Pattern

Use gmeow:celestialEpoch from gmeow:CelestialCoordinates to xsd:decimal when the relationship itself belongs in the native GMEOW graph.

Common Companion Terms

gmeow:CelestialCoordinates

Usage Advice

Use when

• Use for the epoch (Julian year) for which celestial coordinates are expressed — required for proper-motion propagation.

Avoid when

• Avoid omitting it for moving bodies and avoid confusing it with the temporal slice's observation time.

How to use

• Add gmeow:celestialEpoch to CelestialCoordinates alongside the frame; frame-relative per Principle 11.

Examples

• ex:vegaCoords gmeow:celestialEpoch 2000.0.