Module model 

Public time model type family.

A bare Epoch is ambiguous (element epoch vs observation epoch vs product epoch), so the public surface is a concrete family of types that always name their scale and use a precision-preserving representation:

• TimeScale - the named time scale of an instant.
• Instant - a scale + a split-Julian-date / integer-nanosecond repr.
• Duration - an integer-nanosecond elapsed interval.
• JulianDateSplit - the two-part (whole + fraction) Julian date used to avoid catastrophic cancellation, matching the Skyfield split convention.
• GnssWeekTow - a GNSS week number + time-of-week with rollover handling.

These are representation/value types only. The parity-critical conversion numerics live in crate::astro::time::scales; this module deliberately holds no transcendental math so it cannot perturb the 0-ULP contract.

Re-exports

pub use crate::astro::constants::time::SECONDS_PER_WEEK;

Structs

Duration

An elapsed interval, stored as exact integer nanoseconds.

GnssWeekTow

A GNSS week number + time-of-week, tagged by constellation.

Instant

A point in time, always tagged with its TimeScale.

JulianDateSplit

Two-part Julian date (whole day boundary + day fraction).

Enums

InstantRepr

Internal representation backing an Instant.

TimeModelError

Error returned when constructing public time model values from invalid input.

TimeScale

Named time scales supported by the time model.