Semi-Major Axis From Period Calculator
Inverseidealpointmasstwo-bodyKeplerperiodsemi-majoraxis,centralμincludesactualtotalmass whenapplicable,not keplerperioddirection. Actual independent model/unit/frame/epoch/calibration and applicable measurement established;not precise ephemeris,forecast,geodesy operation,identity or safety approval.
Description
Kepler’s two-body period relation connects a bound orbit’s period with its semi-major axis.
Kepler’s two-body period relation connects a bound orbit’s period with its semi-major axis.1
This calculator needs the applicable gravitational parameter and period, with coherent units and the relevant masses already accounted for.
When to use Semi-Major Axis From Period Calculator
Use this tool to apply the stated semi-major axis from period calculator operation with an explicit input and unit basis.
How to use Semi-Major Axis From Period Calculator and how it works
- Establish the measurement basis and units described above.
- Enter actualCentralGravitationalParameter, actualOrbitalPeriodSeconds and run the tool.
- Read result.value using the output meanings below.
- If input is rejected, correct the stated type, range, ordering or alignment issue and rerun; review successful results under the declared convention.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| actualCentralGravitationalParameter | Central Gravitational Parameter. Units, ordering and applicable branch are specified in the algorithm. | number | required; finite; strictly positive; further conditions in the algorithm |
| actualOrbitalPeriodSeconds | Orbital Period Seconds. Units, ordering and applicable branch are specified in the algorithm. | number | required; finite; strictly positive; further conditions in the algorithm |
Require positive gravitational parameter and positive period in seconds. Cube-root μT²/(4π²); SI μ in m³/s² gives meters. Perturbations and an orbital fit are not included.
a = (μT²/(4π²))^(1/3) Apply the declared units, ordering and branch conditions.
| Output field | Meaning | Value type |
|---|---|---|
| result | Object containing the declared output fields. | object |
| result.value | Two-body semi-major axis; meters when μ is m³/s² and period is seconds. | number |
{
"input": {
"actualCentralGravitationalParameter": 1,
"actualOrbitalPeriodSeconds": 6.283185307179586
},
"output": {
"result": {
"value": 1
}
}
}Limitations and assumptions
The output applies the declared operation to the values you supply. Establish the measurement basis, units, coefficients and any caller-selected rules before interpreting it. The tool does not independently collect or verify observations or decide whether a model or reference applies.
Supply explicit required fields with the documented types and dense aligned arrays. Unknown fields, wrong types and nonfinite numbers are rejected. Branch-specific constraints are explained above. A returned boolean, signed difference or tied result follows the stated convention; an input error instead means the required input contract was not satisfied. Very large inputs or outputs may be rejected by shared resource limits.
Alternative or Complementary methods
For a related operation, use Exoplanet Surface Gravity Calculator. Surface gravity is gravitational acceleration at the radius of an ideal spherical body.
For a related operation, use Exoplanet Density g/cm³ Calculator. Bulk density combines a body’s mass with an assumed spherical volume.
References
-
Semi-Major Axis From Period Calculator — tool.io
Similar or alternative tools
- Exoplanet Surface Gravity Calculator
Surface gravity is gravitational acceleration at the radius of an ideal spherical body.
- Exoplanet Density g/cm³ Calculator
Bulk density combines a body’s mass with an assumed spherical volume.