Ephemerides File Formats

When uploading an ephemerides file to the conjunction screener, you must make sure the file conforms to a format accepted by LeoLabs. All accepted formats will appear here.

LeoLabs Ephemerides Format (.json)

Example

{ "frame": "EME2000", "covarianceFrame": "EME2000", "states": [ { "timestamp": "2018-09-01T00:00:00.000000Z", "position": [-5484195.91111, -3551473.37188, -3037406.26973], "velocity": [-3238.19794, -625.65498, 6673.63105], "covariance": [ [416.62551, 79.83265, -846.92739, -0.74601, -0.48334, -0.41306], [79.83265, 23.21858, -170.89165, -0.14946, -0.09708, -0.08245], [-846.92739, -170.89165, 1737.27757, 1.52604, 0.98898, 0.84769], [-0.74601, -0.14946, 1.52604, 0.00134, 0.00087, 0.00075], [-0.48334, -0.09708, 0.98898, 0.00087, 0.00057, 0.00048], [-0.41306, -0.08245, 0.84769, 0.00075, 0.00048, 0.00041] ] } ] }

Definition

frame Frame of included ephemerides. This parameter is required. Currently the only accepted frame is 'EME2000'.
covarianceFrame Frame of included covariances. Currently the only accepted frame is 'EME2000'.
states Array of state objects as defined below. This parameter is required.

state

timestamp ISO-8601 timestamp of the ephemeris. This parameter is required. Note that the steps between the timestamps must be less than or equal to 180 seconds.
position Tuple in the EME2000 frame for the position of the object in meters. This parameter is required.
velocity Tuple in the EME2000 frame for the velocity of the object in meters per second. This parameter is required.
covariance A 6x6 matrix of the position and velocity covariances.

STK Ephemeris File Format (.e)

Example

stk.v.4.3 WV04 % spacecraft ID 12345 to -99999 % start and end rev numbers 2019-02-21T14:00:00.000000Z % start epoch 2019-02-21T16:04:12.000000Z WV04_20190221140000-20190323140000.odp500_A.pre ODP 500 2019-02-21T16:04:12.000000Z BEGIN Ephemeris NumberOfEphemerisPoints 4 ScenarioEpoch 21 Feb 2019 14:00:00.000000 InterpolationMethod Hermite EphemerisECFTimePosVel 0.000000 1241326.870 34634.290 6872428.640 4882.419 -5790.786 -860.822 180.000000 2077732.410 -1012982.600 6588857.080 4381.716 -5810.725 -2280.277 360.000000 2809003.860 -2043211.430 6056606.510 3718.872 -5597.394 -3615.201 540.000000 3408620.000 -3014245.950 5295499.010 2924.417 -5154.411 -4815.045 END Ephemeris

Definition

A full definition of the STK Ephemeris File Format can be found on AGI's website here.

CCSDS OEM Format (.oem)

Example

CCSDS_OEM_VERS = 2.0 CREATION_DATE = 2019-08-02T03:04:05.123456 ORIGINATOR = LEOLABS META_START OBJECT_NAME = EXAMPLE SAT 1 OBJECT_ID = L999999 CENTER_NAME = EARTH REF_FRAME = EME2000 TIME_SYSTEM = UTC START_TIME = 2019-03-18T00:00:00 USEABLE_START_TIME = 2019-03-18T00:00:00 USEABLE_STOP_TIME = 2019-03-19T00:00:00 STOP_TIME = 2019-03-19T00:00:00Z INTERPOLATION = LAGRANGE INTERPOLATION_DEGREE = 7 META_STOP 2019-03-18T00:00:00 -1.898076e+06 -6.216728e+06 2.960030e+06 -2.023501e+03 -2.589406e+03 -6.711289e+03 ... COVARIANCE_START EPOCH = 2019-03-18T00:00:00 COV_REF_FRAME = EME2000 4.31661235e+03 -1.47401855e+03 9.56942996e+02 -4.66631183e+02 1.03895014e+03 2.00120455e+03 1.20240463e+00 -7.73289709e-01 -8.91178565e-01 7.16431890e-04 -7.22705016e-01 -6.29054148e-01 -1.82716096e+00 5.40286462e-04 2.06419602e-03 -1.47749402e-01 4.69618107e-01 1.04863201e+00 -4.48718604e-04 -9.97646457e-04 6.06341102e-04 ... COVARIANCE_STOP

Definition

A full definition of the CCSDS OEM format can be found on the CCSDS website here.

Two-Line Element Set Format (TLE)

The TLE file can have no title line or a title line with or without a leading 0. All three of the following examples are valid.

Examples

0 ENVISAT 1 27386U 02009A 19151.09138118 -.00000007 00000-0 11277-4 0 9995 2 27386 98.1501 173.0678 0001263 90.2390 338.9683 14.37949482903529 ENVISAT 1 27386U 02009A 19151.09138118 -.00000007 00000-0 11277-4 0 9995 2 27386 98.1501 173.0678 0001263 90.2390 338.9683 14.37949482903529 1 27386U 02009A 19151.09138118 -.00000007 00000-0 11277-4 0 9995 2 27386 98.1501 173.0678 0001263 90.2390 338.9683 14.37949482903529

Definition

An in-depth explanation and definition of the TLE format can be found on NASA's website here.