US Space Command

US Space Command Conjunction Data API

Conjunction data messages (collision warnings)

Documentation GitHub OpenAPI

Operations 1

GET /basicspacedata/query/class/cdm_public/format/{format} List Conjunction Data Messages (CDM) #

Work with this as data

Every API here is available over the APIs.io API and to AI agents over MCP.

MCP server

One button, every client — Claude, Cursor, VS Code and the rest.

https://apis.io/mcp

Tools for apis

7 MCP tools reach this

find_apisBrowse and filter every API in the catalog.
get_api_artifactsOne API's artifacts, grouped by type.
get_openapiThe primary OpenAPI for this API.
find_similar_apisAPIs that look like this one.
apis_io_searchSTART HERE — APIs, providers and tags for one query, each with its total.
resolveTurn a domain, URL or GitHub org into the provider it belongs to.
find_cohortsEvery scored population of providers in the catalog.

All 92 tools →

Call it yourself

curl for this page

This API

curl "https://apis.io/api/v1/apis/us-space-comman-conjunction-data-api"

All apis

curl "https://apis.io/api/v1/apis?limit=25"

Discovery needs no key. Ratings and market analysis are Pro.

Get an API key

Free tier, no form to fill in. Signing in shares your email address with us — we store it to create your key and to recognise you if you sign in with another provider. See our Privacy Policy and Terms.

GitHub Google LinkedIn

A second provider on the same verified email joins the account you already have.

OpenAPI Specification

openapi: 3.2.0
info:
  title: Space-Track.org REST Authentication Conjunction Data API
  description: Space-Track.org is the official US Space Command (USSPACECOM) source for space situational awareness data. The REST API provides access to the satellite catalog (SATCAT), orbital element sets (GP/TLEs), conjunction data messages (CDMs), decay predictions (TIP), and space object history. Requires a free account. Authenticate via POST to /ajaxauth/login then use session cookies for subsequent requests.
  version: '1.0'
  contact:
    name: US Space Command / 18th Space Defense Squadron
    url: https://www.space-track.org
servers:
- url: https://www.space-track.org
security:
- sessionCookie: []
tags:
- name: Conjunction Data
  description: Conjunction data messages (collision warnings)
paths:
  /basicspacedata/query/class/cdm_public/format/{format}:
    get:
      tags:
      - Conjunction Data
      operationId: listConjunctionData
      summary: List Conjunction Data Messages (CDM)
      description: Returns publicly available Conjunction Data Messages (CDMs), which are notifications of potential close approaches between tracked objects. Sorted by collision probability descending.
      parameters:
      - name: format
        in: path
        required: true
        schema:
          type: string
          enum:
          - json
          - xml
          - csv
          default: json
      - name: SAT_1_ID
        in: query
        description: NORAD ID of primary object
        schema:
          type: string
      - name: SAT_2_ID
        in: query
        description: NORAD ID of secondary object
        schema:
          type: string
      - name: TCA_RANGE_START
        in: query
        description: Time of closest approach start filter (ISO 8601)
        schema:
          type: string
      - name: TCA_RANGE_END
        in: query
        description: Time of closest approach end filter (ISO 8601)
        schema:
          type: string
      - name: PC
        in: query
        description: Probability of collision filter (e.g., >0.0001)
        schema:
          type: string
      - name: MISS_DISTANCE
        in: query
        description: Miss distance filter (km)
        schema:
          type: string
      - name: orderby
        in: query
        schema:
          type: string
      - name: limit
        in: query
        schema:
          type: integer
      responses:
        '200':
          description: Conjunction data messages
          content:
            application/json:
              schema:
                type: array
                items:
                  $ref: '#/components/schemas/ConjunctionDataMessage'
        '401':
          description: Unauthorized
components:
  schemas:
    ConjunctionDataMessage:
      type: object
      description: Conjunction Data Message indicating potential close approach
      properties:
        CDM_ID:
          type: integer
        CREATED:
          type: string
          format: date-time
        EMERGENCY_REPORTABLE:
          type: string
        TCA:
          type: string
          format: date-time
          description: Time of closest approach
        MIN_RNG:
          type: number
          description: Minimum range (km)
        PC:
          type: number
          description: Probability of collision
        SAT_1_ID:
          type: integer
          description: NORAD ID of primary object
        SAT_1_NAME:
          type: string
        SAT_2_ID:
          type: integer
          description: NORAD ID of secondary object
        SAT_2_NAME:
          type: string
        SAT_1_TYPE:
          type: string
        SAT_2_TYPE:
          type: string
        MISS_DISTANCE:
          type: number
          description: Miss distance (km)
  securitySchemes:
    sessionCookie:
      type: apiKey
      in: cookie
      name: chocolatechip
      description: Session cookie obtained after successful login via POST /ajaxauth/login