Get the current ephemeris for a satellite - AWS Ground Station
Example GetSatellite return for a satellite using a default ephemerisExample GetSatellite for a satellite using a custom ephemerisListing azimuth elevation ephemerides

Get the current ephemeris for a satellite

The current ephemeris in use by AWS Ground Station for a specific satellite can be retrieved by calling the GetSatellite or ListSatellites actions. Both of these methods will return metadata for the ephemeris currently in use. This ephemeris metadata is different for custom ephemerides uploaded to AWS Ground Station and for default ephemerides.

Note

Azimuth elevation ephemerides are not associated with satellites and therefore are not returned by GetSatellite or ListSatellites. To retrieve information about azimuth elevation ephemerides, use the DescribeEphemeris API with the specific ephemeris ID, or use ListEphemerides to see all available ephemerides for your account.

Default Ephemerides will only include source and epoch fields. The epoch is the epoch of the two-line element set that was pulled from Space-Track, and it is currently being used for computing the trajectory of the satellite.

A custom ephemeris will have a source value of CUSTOMER_PROVIDED and will include a unique identifier in the ephemerisId field. This unique identifier can be used to query for the ephemeris via the DescribeEphemeris action. An optional name field will be returned if the ephemeris was assigned a name during upload to AWS Ground Station via the CreateEphemeris action.

It is important to note that ephemerides are updated dynamically by AWS Ground Station so the returned data is only a snapshot of the ephemeris being used at the time of the call to the API.

Example GetSatellite return for a satellite using a default ephemeris

{
    "satelliteId": "e1cfe0c7-67f9-4d98-bad2-EXAMPLE",
    "satelliteArn": "arn:aws:groundstation::111122223333:satellite/e1cfe0c7-67f9-4d98-bad2-EXAMPLE",
    "noradSatelliteID": 25994,
    "groundStations": [
        "Ohio 1",
        "Oregon 1"
    ],
    "currentEphemeris": {
        "source": "SPACE_TRACK",
        "epoch": 1528245583.619
    }
}

Example GetSatellite for a satellite using a custom ephemeris

{
      "satelliteId": "e1cfe0c7-67f9-4d98-bad2-EXAMPLE",
      "satelliteArn": "arn:aws:groundstation::111122223333:satellite/e1cfe0c7-67f9-4d98-bad2-EXAMPLE",
      "noradSatelliteID": 25994,
      "groundStations": [
            "Ohio 1",
            "Oregon 1"
      ],
      "currentEphemeris": {
          "source": "CUSTOMER_PROVIDED",
          "ephemerisId": "e1cfe0c7-67f9-4d98-bad2-EXAMPLE",
          "name": "My Ephemeris"
      }
  }

Listing azimuth elevation ephemerides

Since azimuth elevation ephemerides are not associated with satellites, you need to use different APIs to discover and retrieve information about them:

  1. Use ListEphemerides to list all ephemerides in your account, including azimuth elevation ephemerides. You can filter by status and ephemeris type.

  2. Use DescribeEphemeris with a specific ephemeris ID to get detailed information about an azimuth elevation ephemeris.

  3. Use DescribeContact with a specific contact ID to get detailed information about an ephemeris used for the contact.

Example ListEphemerides response including an azimuth elevation ephemeris: 

{
    "ephemerides": [
        {
            "ephemerisId": "abc12345-6789-def0-1234-5678EXAMPLE",
            "ephemerisType": "AZ_EL",
            "name": "Azimuth Elevation for Ohio Ground Station",
            "status": "ENABLED",
            "creationTime": 1620254718.765
        },
        {
            "ephemerisId": "def45678-9012-abc3-4567-8901EXAMPLE",
            "ephemerisType": "TLE",
            "name": "TLE for Satellite 12345",
            "status": "ENABLED",
            "creationTime": 1620254700.123
        }
    ]
}
Note

In the ListEphemerides response, azimuth elevation ephemerides will have a groundStation field instead of a satelliteId field, making them easy to identify.