Space-Track Conjunction Data API

Spaceflight safety conjunction data messages (CDM)

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OpenAPI Specification

spacetrack-conjunction-data-api-openapi.yml Raw ↑
openapi: 3.0.3
info:
  title: Space-Track Ancillary Conjunction Data API
  description: US military space surveillance REST API operated by the 18th Space Control Squadron. Provides Two-Line Element (TLE) sets, conjunction data messages, orbital element sets, satellite catalog data, and decay predictions for all tracked Earth-orbiting objects and debris.
  version: 1.0.0
  contact:
    name: Space-Track Support
    url: https://www.space-track.org/contactus/
  termsOfService: https://www.space-track.org/documentation#user-agreement
  x-logo:
    url: https://www.space-track.org/favicon.ico
servers:
- url: https://www.space-track.org
  description: Space-Track production server
tags:
- name: Conjunction Data
  description: Spaceflight safety conjunction data messages (CDM)
paths:
  /basicspacedata/query/class/cdm_public/{queryParams}:
    get:
      summary: Query public Conjunction Data Messages (CDM)
      description: 'Returns conjunction data messages for close approaches between tracked objects. Rate limit: 3 queries per day for all conjunctions; 1 per hour for specific events.'
      operationId: queryCDMPublic
      tags:
      - Conjunction Data
      parameters:
      - $ref: '#/components/parameters/queryParams'
      responses:
        '200':
          description: Conjunction data message records
          content:
            application/json:
              schema:
                type: array
                items:
                  $ref: '#/components/schemas/CDMRecord'
            text/csv:
              schema:
                type: string
            application/xml:
              schema:
                type: string
                description: CCSDS CDM XML format
        '401':
          $ref: '#/components/responses/Unauthorized'
        '429':
          $ref: '#/components/responses/RateLimited'
      security:
      - sessionCookie: []
  /expandedspacedata/query/class/cdm/{queryParams}:
    get:
      summary: Query full Conjunction Data Messages (CDM)
      description: Returns full conjunction data messages from the expanded space data controller. Requires elevated access. Contains complete CCSDS-compliant CDM data including covariance matrices.
      operationId: queryCDM
      tags:
      - Conjunction Data
      parameters:
      - $ref: '#/components/parameters/queryParams'
      responses:
        '200':
          description: Full CDM records
          content:
            application/json:
              schema:
                type: array
                items:
                  $ref: '#/components/schemas/CDMRecord'
            application/xml:
              schema:
                type: string
        '401':
          $ref: '#/components/responses/Unauthorized'
        '429':
          $ref: '#/components/responses/RateLimited'
      security:
      - sessionCookie: []
  /expandedspacedata/query/class/car/{queryParams}:
    get:
      summary: Query Conjunction Assessment Results (CAR)
      description: Returns conjunction assessment result records from the expanded space data controller.
      operationId: queryCAR
      tags:
      - Conjunction Data
      parameters:
      - $ref: '#/components/parameters/queryParams'
      responses:
        '200':
          description: CAR records
          content:
            application/json:
              schema:
                type: array
                items:
                  type: object
                  description: Conjunction assessment result
        '401':
          $ref: '#/components/responses/Unauthorized'
      security:
      - sessionCookie: []
components:
  responses:
    Unauthorized:
      description: Authentication required. Login at /ajaxauth/login first to obtain a session cookie.
    RateLimited:
      description: Rate limit exceeded. Maximum 30 requests per minute or 300 per hour globally. Per-class rate limits also apply.
  schemas:
    CDMRecord:
      type: object
      description: Conjunction Data Message (CDM) record following CCSDS standard
      properties:
        CDM_ID:
          type: string
          description: Unique CDM identifier
        CREATED:
          type: string
          format: date-time
          description: CDM creation date-time in UTC
        EMERGENCY_REPORTABLE:
          type: string
          description: Whether the conjunction is emergency reportable (Y/N)
        TCA:
          type: string
          format: date-time
          description: Time of closest approach in UTC
        MIN_RNG:
          type: string
          description: Minimum range at TCA in meters
        PC:
          type: string
          description: Probability of collision
        SAT1_ID:
          type: string
          description: NORAD catalog ID of first object
        SAT1_NAME:
          type: string
          description: Name of first object
        SAT1_OBJECT_TYPE:
          type: string
          description: Type of first object
        SAT1_RCS:
          type: string
          description: RCS of first object
        SAT2_ID:
          type: string
          description: NORAD catalog ID of second object
        SAT2_NAME:
          type: string
          description: Name of second object
        SAT2_OBJECT_TYPE:
          type: string
          description: Type of second object
        SAT2_RCS:
          type: string
          description: RCS of second object
        SAT2_EXCL_VOL:
          type: string
          description: Exclusion volume for second object
  parameters:
    queryParams:
      name: queryParams
      in: path
      required: false
      description: 'Flexible REST query path segments. Format: /FIELD/VALUE/FIELD2/VALUE2/format/FORMAT/. Supports operators: range (--), greater-than (%3E), less-than (%3C), null (null-val), comma lists. Example: /NORAD_CAT_ID/25544/format/json/'
      schema:
        type: string
        default: ''
        example: NORAD_CAT_ID/25544/format/json/
  securitySchemes:
    sessionCookie:
      type: apiKey
      in: cookie
      name: chocolatechip
      description: Session cookie obtained by POSTing credentials to /ajaxauth/login
x-query-guide:
  syntax: 'REST queries use path segments: /class/{class}/FIELD/VALUE/format/FORMAT/'
  operators:
    exact: /FIELD/VALUE/
    range: /FIELD/START--END/
    greaterThan: /FIELD/%3EVALUE/
    lessThan: /FIELD/%3CVALUE/
    commaList: /FIELD/V1,V2,V3/
    nullValue: /FIELD/null-val/
    notNull: /FIELD/null-val/exclude/
  formats:
  - json
  - csv
  - xml
  - html
  - tle
  - 3le
  - kvn
  commonFilters:
    currentEpoch: EPOCH/%3Enow-30
    specificObject: NORAD_CAT_ID/25544
    multipleObjects: NORAD_CAT_ID/25544,43873,44506
    catalogRange: NORAD_CAT_ID/25000--26000
    recentMessages: MSG_EPOCH/%3Enow-1