Namespaces
namespace	detail

Classes
struct	TargetFacts
	Target identity and provider domains; rate_node preserves the paired ascending trajectory. More...
struct	Position
	Apparent geocentric coordinates in the true ecliptic and equinox of date. More...
struct	EquatorialPosition
	Apparent geocentric equatorial coordinates of date; nodes have no physical distance. More...
struct	LongitudeRate
	A signed instantaneous longitude rate; a negative value means longitude is decreasing at that instant. More...
struct	LongitudeEvent
	A crossing or exact numerical contact at a supplied longitude. More...
struct	StationEvent
	A stationary instant of the published finite-difference rate, with its two-sided motion. More...
struct	LongitudeDifferenceEvent
	An event in the directed, canonical longitude difference first minus second. More...

Enumerations
enum class	Target : uint8_t { SUN , MOON , MERCURY , VENUS , MARS , JUPITER , SATURN , URANUS , NEPTUNE , PLUTO , MEAN_ASCENDING , MEAN_DESCENDING , TRUE_ASCENDING , TRUE_DESCENDING }
	A body or lunar node. More...
enum class	PositionSource : uint8_t { SUN_VSOP87D , MOON_ELP2000_82B_TRUNC , PLANET_VSOP87D , PLUTO_PLUTO95_APPARENT , NODE_MEAN , NODE_TRUE_MEEUS_FIVE_TERM }
	The computation supplying a target's apparent position. More...
enum class	DomainOrigin : uint8_t { SOURCE , IMPLEMENTATION }
	Origin of a bounded position domain; ignored when no position domain is declared. More...
enum class	EventDirection : uint8_t { INCREASING , DECREASING , TANGENT }
	Behavior of an angular level on the two sides of an event. More...
enum class	Motion : uint8_t { DIRECT , RETROGRADE }
	The sign of longitude motion away from a stationary instant. More...

Functions
constexpr auto	is_target (const Target target) -> bool
	Recognize named Target values; new distinct enumerators must also enter TARGET_FACTS.
constexpr auto	target_facts (const Target target) -> const TargetFacts &
	Look up a named target; unknown values are invalid arguments.
constexpr auto	source_of (const Target target) -> PositionSource
	The source of a named target's apparent position.
constexpr auto	position_domain (const Target target) -> std::optional< std::array< double, 2 > >
	Half-open provider domain, or no hard interval; neither implies accuracy or successful evaluation.
auto	position (const Target target, const double jde_tt) -> Position
	Evaluate one target's apparent position without a rate stencil or civil policy.
auto	equatorial_position (const Target target, const double jde_tt) -> EquatorialPosition
	Project one apparent ecliptic position to geocentric apparent RA/Dec of date.
constexpr auto	longitude_rate_domain (const Target target) -> std::array< double, 2 >
	Return the half-open center domain of a target's longitude-rate operation.
auto	longitude_rate (const Target target, const double jde_tt) -> LongitudeRate
	Instantaneous geocentric longitude rate using the target's position model.
auto	longitude_events (const Target target, const toolbox::AngleDeg target_longitude, const double start_jde_tt, const double end_jde_tt) -> std::vector< LongitudeEvent >
	Return every crossing or exact numerical contact at a supplied tropical longitude.
auto	stations (const Target target, const double start_jde_tt, const double end_jde_tt) -> std::vector< StationEvent >
	Return every isolated zero of ephemeris::longitude_rate in a half-open TT interval.
auto	longitude_difference_events (const Target first, const Target second, const toolbox::AngleDeg target_difference, const double start_jde_tt, const double end_jde_tt) -> std::vector< LongitudeDifferenceEvent >
	Return every event at a directed longitude difference, first minus second.

Variables
constexpr auto	TARGET_FACTS
	Target facts in chart order; absent position domains admit finite-input evaluation, which may fail.
constexpr auto	TARGETS
	The target roster, derived from the facts table in chart order.
constexpr double	EVENT_MAXIMUM_QUERY_SPAN_TT_DAYS
	Maximum nonempty event-query span in TT days.

Enumeration Type Documentation

◆ DomainOrigin

enum class astro::ephemeris::DomainOrigin : uint8_t

strong

Origin of a bounded position domain; ignored when no position domain is declared.

Enumerator
SOURCE
IMPLEMENTATION

◆ EventDirection

enum class astro::ephemeris::EventDirection : uint8_t

strong

Behavior of an angular level on the two sides of an event.

Enumerator
INCREASING
DECREASING
TANGENT

◆ Motion

enum class astro::ephemeris::Motion : uint8_t

strong

The sign of longitude motion away from a stationary instant.

Enumerator
DIRECT
RETROGRADE

◆ PositionSource

enum class astro::ephemeris::PositionSource : uint8_t

strong

The computation supplying a target's apparent position.

Enumerator
SUN_VSOP87D
MOON_ELP2000_82B_TRUNC
PLANET_VSOP87D
PLUTO_PLUTO95_APPARENT
NODE_MEAN
NODE_TRUE_MEEUS_FIVE_TERM	Meeus' five-term approximation, not an osculating node.

◆ Target

enum class astro::ephemeris::Target : uint8_t

strong

A body or lunar node.

Enumerator
SUN
MOON
MERCURY
VENUS
MARS
JUPITER
SATURN
URANUS
NEPTUNE
PLUTO
MEAN_ASCENDING
MEAN_DESCENDING
TRUE_ASCENDING
TRUE_DESCENDING

Function Documentation

◆ equatorial_position()

auto astro::ephemeris::equatorial_position	(	const Target	target,
		const double	jde_tt )->EquatorialPosition

inlinenodiscard

Project one apparent ecliptic position to geocentric apparent RA/Dec of date.

Parameters

target	A named ephemeris target.
jde_tt	Finite JDE(TT), within the target's declared provider window.

Returns: RA in [0, 360) and declination in [-90, 90] degrees, with physical distance where present.

Exceptions

std::invalid_argument	For malformed or out-of-provider-domain input.
std::runtime_error	If position evaluation or projection produces invalid coordinates.

Note: Longitude nutation and true obliquity use fixed IAU1980; no rate stencil or civil policy applies. Coordinate validity establishes neither accuracy nor physical plausibility at remote epochs.

See also: Jean Meeus, "Astronomical Algorithms", Second Edition, formulas (13.3), (13.4) and (22.2).

◆ is_target()

auto astro::ephemeris::is_target ( const Target target ) ->bool

nodiscardconstexpr

Recognize named Target values; new distinct enumerators must also enter TARGET_FACTS.

◆ longitude_difference_events()

auto astro::ephemeris::longitude_difference_events	(	const Target	first,
		const Target	second,
		const toolbox::AngleDeg	target_difference,
		const double	start_jde_tt,
		const double	end_jde_tt )->std::vector< LongitudeDifferenceEvent >

inlinenodiscard

Return every event at a directed longitude difference, first minus second.

Parameters

first	The first moving body or node.
second	A distinct supported target.
target_difference	A finite signed angle, canonicalized to (-180,180] degrees.
start_jde_tt	Inclusive start, within the intersection of the two longitude_rate_domain windows.
end_jde_tt	Exclusive end; the nonempty span must not exceed 3660 TT days.

Returns: Ordered crossings and exact numerical relative-station contacts, or an empty list for a constant miss.

Exceptions

std::invalid_argument For self-pairs, continuously satisfied relations or malformed/out-of-window inputs.

Note: Numerical uncertainty or work-limit exhaustion throws, never returns a prefix. The floating-point premises and numerical-contact equality rule are the same as for longitude_events.

◆ longitude_events()

auto astro::ephemeris::longitude_events	(	const Target	target,
		const toolbox::AngleDeg	target_longitude,
		const double	start_jde_tt,
		const double	end_jde_tt )->std::vector< LongitudeEvent >

inlinenodiscard

Return every crossing or exact numerical contact at a supplied tropical longitude.

Parameters

target	The moving body or node.
target_longitude	A finite angle; whole-turn shifts denote the same level.
start_jde_tt	Inclusive start, within longitude_rate_domain.
end_jde_tt	Exclusive end; the nonempty span must not exceed 3660 TT days.

Returns: Chronologically ordered events, with no partial result on numerical or work-limit failure.

Note: Completeness is conditional on the floating-point and elementary-function contract in Longitude events. A tangent requires exact equality with the query-independent stationary output, not angular proximity.

◆ longitude_rate()

auto astro::ephemeris::longitude_rate	(	const Target	target,
		const double	jde_tt )->LongitudeRate

inlinenodiscard

Instantaneous geocentric longitude rate using the target's position model.

Parameters

jde_tt JDE(TT).

Returns: Longitude rate in the true ecliptic and equinox of date.

Exceptions

std::invalid_argument	For invalid arguments, out-of-domain samples or inexact sample offsets.
std::runtime_error	If numerical evaluation fails.

Note: Seven-point centered difference at 1/8 TT day spacing, sampling up to 3/8 TT day each way.; Center domains: Pluto [2409543.875, 2488069.125); nodes [2409542.875, 2488069.125); others [-1200954.625, 6104044.625).; Descending-node rates equal ascending-node rates.

◆ longitude_rate_domain()

auto astro::ephemeris::longitude_rate_domain ( const Target target ) ->std::array< double, 2 >

nodiscardconstexpr

Return the half-open center domain of a target's longitude-rate operation.

Parameters

target A named ephemeris target.

Returns: Inclusive start and exclusive end in JDE(TT), allowing the full sampled reach.

Exceptions

std::invalid_argument If the target is unknown.

Note: This window bounds the rate operation, not the target's position model. Exact sample-offset representability is checked separately by longitude_rate.

◆ position()

auto astro::ephemeris::position	(	const Target	target,
		const double	jde_tt )->Position

inlinenodiscard

Evaluate one target's apparent position without a rate stencil or civil policy.

Parameters

target	A named ephemeris target.
jde_tt	Finite JDE(TT), within the provider window where one is declared.

Returns: Longitude in [0, 360), latitude in [-90, 90] degrees, and positive distance where physical.

Exceptions

std::invalid_argument	For malformed or out-of-provider-domain input.
std::runtime_error	If computation fails or produces invalid coordinates.

Note: Where no hard input interval is declared, finite-input evaluation gives no accuracy or plausibility guarantee.

◆ position_domain()

auto astro::ephemeris::position_domain ( const Target target ) ->std::optional< std::array< double, 2 > >

nodiscardconstexpr

Half-open provider domain, or no hard interval; neither implies accuracy or successful evaluation.

◆ source_of()

auto astro::ephemeris::source_of ( const Target target ) ->PositionSource

nodiscardconstexpr

The source of a named target's apparent position.

◆ stations()

auto astro::ephemeris::stations	(	const Target	target,
		const double	start_jde_tt,
		const double	end_jde_tt )->std::vector< StationEvent >

inlinenodiscard

Return every isolated zero of ephemeris::longitude_rate in a half-open TT interval.

Parameters

target	The moving body or node.
start_jde_tt	Inclusive start, within longitude_rate_domain.
end_jde_tt	Exclusive end; the nonempty span must not exceed 3660 TT days.

Returns: Ordered stationary instants and the certified motion on both sides.

Note: The reported finite-difference rate need not be exactly zero. Unresolved isolation or refinement throws. The floating-point premises are the same as for longitude_events.

◆ target_facts()

auto astro::ephemeris::target_facts ( const Target target ) ->constTargetFacts &

nodiscardconstexpr

Look up a named target; unknown values are invalid arguments.

Variable Documentation

◆ EVENT_MAXIMUM_QUERY_SPAN_TT_DAYS

double astro::ephemeris::EVENT_MAXIMUM_QUERY_SPAN_TT_DAYS

inlineconstexpr

Maximum nonempty event-query span in TT days.

Note: About ten years per request; an admission limit independent of evaluation/candidate exhaustion.

◆ TARGET_FACTS

auto astro::ephemeris::TARGET_FACTS

inlineconstexpr

Target facts in chart order; absent position domains admit finite-input evaluation, which may fail.

◆ TARGETS

auto astro::ephemeris::TARGETS

inlineconstexpr

The target roster, derived from the facts table in chart order.

Namespaces

Classes

Enumerations

Functions

Variables

Enumeration Type Documentation

◆ DomainOrigin

◆ EventDirection

◆ Motion

◆ PositionSource

◆ Target

Function Documentation

◆ equatorial_position()

◆ is_target()

◆ longitude_difference_events()

◆ longitude_events()

◆ longitude_rate()

◆ longitude_rate_domain()

◆ position()

◆ position_domain()

◆ source_of()

◆ stations()

◆ target_facts()

Variable Documentation

◆ EVENT_MAXIMUM_QUERY_SPAN_TT_DAYS

◆ TARGET_FACTS

◆ TARGETS