Equation of the Equinoxes Component Summator
Equation-of-equinoxes leadingΔψcosεplus caller independently edition-matched additional terms; not generate IAU series or double-count already full term. Caller independently establishes frames, units, epoch, covariance and instrument context; not an identity, association or astrometric quality certification.
Description
The equation of the equinoxes connects nutation terms with sidereal-time conventions.
The equation of the equinoxes connects nutation terms with sidereal-time conventions.1
Its inputs must use a consistent model rather than unrelated independently tabulated epochs. Use Equation of the Equinoxes Component Summator to evaluate the supplied inputs under the model explained below.
When to use Equation of the Equinoxes Component Summator
Use Equation of the Equinoxes Component Summator to evaluate the supplied inputs under the model explained below. Establish the units, measurement scope and model assumptions before entering values.
How to use Equation of the Equinoxes Component Summator and understand its results
- Establish the units, measurement scope and model assumptions before entering values.
- Enter Independently computed nutation longitude arcsec, Independently computed true obliquity degrees, Caller additional equinox terms arcsec using the field table and validation rules below, then run the tool.
- Read Equation of equinoxes arcsec; interpret the units, signs, ordering and unknown-value placeholders described below.
- Correct reported input errors and rerun. Apply successful results according to their specific meanings and check the assumptions before using them in a decision.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| independentlyComputedNutationLongitudeArcsec | Independently computed nutation longitude arcsec | number | Required; constraints below |
| independentlyComputedTrueObliquityDegrees | Independently computed true obliquity degrees | number | Required; constraints below |
| callerAdditionalEquinoxTermsArcsec | Caller additional equinox terms arcsec | array of number | Required; constraints below |
Enter finite nutation longitude in arcsec, true obliquity from 0 to 90 degrees and finite additional terms in arcsec. Return longitude×cos(obliquity)+sum(additional). An empty additional array is accepted. No nutation theory, epoch matching or apparent/mean sidereal-time solution is calculated.
equationEquinoxesArcsec=nutationLongitudeArcsec×cos(obliquity)+ΣcallerAdditionalTerms Use the field order, units and branch conditions described above.
| Output field | Meaning | Value type |
|---|---|---|
| equationOfEquinoxesArcsec | Equation of equinoxes arcsec | number |
{
"input": {
"independentlyComputedNutationLongitudeArcsec": 10,
"independentlyComputedTrueObliquityDegrees": 60,
"callerAdditionalEquinoxTermsArcsec": [
1,
-0.5
]
},
"output": {
"equationOfEquinoxesArcsec": 5.500000000000001
}
}Limitations and assumptions
Its inputs must use a consistent model rather than unrelated independently tabulated epochs. Apply the exact scope and assumptions explained above.
All listed fields require explicit values. Unexpected fields, incorrect types, nonfinite numbers and sparse arrays fail validation. Domain-specific bounds, alignments and supported tokens are explained above; extremely large inputs or outputs can also be rejected. Input errors differ from successful false results, empty match lists and unknown-evidence placeholders.
Alternative or Complementary methods
Use Hour Angle from Right Ascension and LST Solver for a related task: Hour angle measures local sidereal time relative to right ascension.
Use Transit Time Upper Culmination Hour Finder for a related task: Upper culmination occurs when local sidereal time matches right ascension.
References
Similar or alternative tools
- Hour Angle from Right Ascension and LST Solver
Hour angle measures local sidereal time relative to right ascension.
- Transit Time Upper Culmination Hour Finder
Upper culmination occurs when local sidereal time matches right ascension.