Orbit Type API¶

The Orbit Type API can determine an "orbit type" for given orbital parameters from the categories maintained by the MPC.

Endpoint¶

https://data.minorplanetcenter.net/api/orbit-type

Method: POST

Input Format¶

The API accepts a JSON object with the following fields. Distances (a and q) are in AU, eccentricity (e) is dimensionless, and inclination (i) is in degrees.

field	description	format	required
`a`	Semi-major axis	float	No (if `q` is provided.)
`q`	Perihelion distance	float	No (if `a` is provided.)
`e`	Eccentricity	float	Yes
`i`	Inclination	float	Yes
`mpcID`	MPC unpacked primary provisional designation	string	Yes (unless `require_mpcID == False`.)
`require_mpcID`	Whether a MPC designation is required.	boolean	No (default: `True`)

Note

mpcID is used to establish precise orbit types for comets and natural satellites. If require_mpcID is set to False, the API will return a best-effort orbit type based on the provided orbital parameters, even if no valid MPC designation is provided.

Response Format¶

The API returns a JSON object with the following fields:

Field	Type	Description
`orbit_type`	integer	Determined orbit type, or `None` if it could not be determined.
`orbit_type_long`	string	A human-readable 'long' name for the orbit type.

Examples¶

Note that a Python Notebook tutorial is also available here.

Python¶

import requests
import json
import sys

payload = {
    "a": 2.5,
    "e": 0.1,
    "i": 5.0,
    "require_mpcID": False
}
response = requests.post("https://data.minorplanetcenter.net/api/orbit-type", json=payload)
response.raise_for_status()
json.dump(response.json(), sys.stdout, indent=4)

Output:

{
    "orbit_type": 11,
    "orbit_type_long": "Middle Main Belt"
}

cURL¶

curl -X POST \
  https://data.minorplanetcenter.net/api/orbit-type \
  -H "Content-type: application/json" \
  -d '{"a": 2.5, "e": 0.1, "i": 5.0, "require_mpcID": false}'