Sidereal versus Synodic Month 27.32 vs 29.53 Day Note Generator
Rounded sidereal/synodic lunar month distinction, not a date-specific ephemeris.
Description
Sidereal versus Synodic Month 27.32 vs 29.53 Day Note Generator: look up a supported built-in reference entry.
A sidereal month measures lunar motion against distant stars, while a synodic month measures recurrence of lunar phases.
This tool returns a built-in reference entry for an exact supported selector. The supported entries and their scope are part of the tool; no website or current external table is queried.
When to use this tool
Use this tool when the supplied inputs match the specific operation described above and you need a repeatable result under its stated convention.
- Check the supported input and output contract against an existing calculation or observation.
- Use the complete example to confirm units, selector spelling and result interpretation.
How to use the tool and how it works
- Enter every field in the input table using the stated units and the exact supported selector spelling where applicable.
- Run the tool. Correct input errors before interpreting an output.
- Read the result fields below; use accompanying flags and the stated sign, boundary or model convention when interpreting a number.
Select sidereal or synodic and return the built-in approximate duration note, 27.32 or 29.53 days respectively.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| month | Month. | Exact value: "sidereal", "synodic" |
| month | Built-in entry |
|---|---|
| "sidereal" | Approximately 27.32 days relative to distant stars. |
| "synodic" | Approximately 29.53 days between repeated lunar phases. |
| Output field | Interpretation |
|---|---|
| result | Object containing the following named result fields. |
| result.reference | The stored entry for the exact selected key; its type may be text, a number or a list. |
{
"input": {
"month": "sidereal"
},
"output": {
"result": {
"reference": "Approximately 27.32 days relative to distant stars."
}
}
}Limitations and assumptions
- These rounded notes are not dates of future phases or a lunar ephemeris.
- Every declared field is required and unexpected fields are rejected. Numeric inputs must be finite; input errors are distinct from a valid false result or an explicitly qualified output.
- Extremely large inputs and nonfinite or excessively large outputs are rejected. List positions reported by the tool use zero-based indices unless stated otherwise.
Alternative or Complementary methods
Check the underlying observations, units and conventions independently before using the result in a larger workflow. The tools listed below address nearby tasks; compare their inputs and scope before substituting one for this operation.
References
Similar or alternative tools
- orbital synodic period
A synodic period describes the repetition of relative alignment between same-direction cycles.
- Synodic Period Earth-Mars 780 day Reference Lookup
Rounded Earth-Mars synodic-period reference, not actual opposition-date or transfer-window prediction.