# Julian Day

{% hint style="info" %}
**All** input dates are assumed to be in the Gregorian calendar. Even if you provide a date earlier than the first adoption of the Gregorian calendar, it is taken as is and is **not** assumed to be a Julian calendar date.
{% endhint %}

### Calculate Julian Day

{% openapi src="<https://api.radiantdrift.com/openapi/0.18.3.json>" path="/julian-day/{date}" method="get" %}
<https://api.radiantdrift.com/openapi/0.18.3.json>
{% endopenapi %}

### Calculate Gregorian Date/Time

{% openapi src="<https://api.radiantdrift.com/openapi/0.18.3.json>" path="/date/{julian-day}" method="get" %}
<https://api.radiantdrift.com/openapi/0.18.3.json>
{% endopenapi %}


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.radiantdrift.com/julian-day.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.