Ephemerides File Formats

The following is a description of the ephemerides file formats LeoLabs accepts. When uploading an ephemerides file to LeoLabs, the file must conform to the accepted formats described below. We accept positions and velocities in EME2000 like frames, and Earth-Centered Earth-Fixed like frames. We accept 3x3 or 6x6 covariance matrices in EME2000 like frames, and RIC like frames. Note that not all features support every format.

We consider EME2000 like frames to be in the set of EME2000, J2000, ECI or similar. We consider Earth-Centered Earth Fixed frames to be in the set of ECEF, ECF or similar. We consider RIC like frames to be in the set of RIC, RTN, UVW or similar. If only a certain set of frames is allowed in a particular format, it is noted below.

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

We currently support STK Ephemeris File Format version between 4.1 and 11.5 inclusive. This includes files where the frame is embedded in the covariance format as shown above, and files where the frame is specified in the header. We expect the units for states and covariances to be in meters and meters/second. We accept the following ephemeris formats with or without the frame inserted, depending on the version: EphemerisTimePosVel, EphemerisTimePosVelAcc. We also accept the following covariance formats: CovarianceTimePos, and CovarianceTimePosVel. 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

We currently accept files for CCSDS_OEM_VERS = 1.0 and 2.0. The states and covariances must be in kilometers and kilometers/second units, as specified in the CCSDS OEM standard. Note that while the standard allows for multiple Metadata, Ephemeris Data, Covariance Matrix (optional) groups, LeoLabs currently only accepts files for which all of the groups are for the same object, and are contiguous in time. A full definition of the CCSDS OEM standard can be found on the CCSDS website here.

NASA Ephemeris Format (.txt)

Example

20049045846.618 3989.0958732016 -17.2373703241 5265.0373968349 0.2752851297 7.8000537922 -0.0977985834 20049045946.618 3995.7122228524 450.4220212004 5246.0851015862 -0.0547273015 7.7821571464 -0.5335448290 20049050046.618 3982.5467942771 915.8522781185 5201.0819191117 -0.3838307864 7.7258060518 -0.9657974479 20049050146.618 3949.7037449032 1376.7581450812 5130.3026640366 -0.7103735730 7.6314316921 -1.3923880559 20049050246.618 3897.3859479376 1830.8761341194 5034.1512933668 -1.0327190651 7.4996667269 -1.8111843232 20049050346.618 3825.8932764985 2275.9868138238 4913.1577549343 -1.3492748761 7.3313402622 -2.2201219941 20049050446.618 3735.6197626329 2709.9256404870 4767.9738469662 -1.6584923658 7.1274537009 -2.6172029029 20049050546.618 3627.0510022233 3130.5934965549 4599.3689679417 -1.9588712490 6.8891842194 -3.0005083844 20049050646.618 3500.7608901143 3535.9667468419 4408.2250981384 -2.2489684390 6.6178702159 -3.3682043499 20049050746.618 3357.4080444428 3924.1068666383 4195.5314613789 -2.5274052972 6.3150080209 -3.7185528644 20049050846.618 3197.7316417491 4293.1694286095 3962.3784935952 -2.7928752957 5.9822364316 -4.0499181170

Definition

Please note that since no frame is specified for the NASA ephemeris format, we only accept files that have states in an EME2000 like frame. Additionally, all units are assumed to be in kilometers and kilometers/second. A full definition of the NASA Ephemeris format can be found on the Space Track website here.

Generic On-Orbit Ephemeris Format (.txt)

Example

created:2020-02-18T05:00:16Z ephemeris_start:2020-02-18T04:58:46Z ephemeris_stop:2020-02-19T12:58:46Z step_size:60.000000 ephemeris_source:jspoc_ephemeris_source_propagation UVW 2020049045846.618 3989.0958732016 -17.2373703241 5265.0373968349 0.2752851297 7.8000537922 -0.0977985834 3.5860219464e-04 -2.2459784351e-02 1.4129779994e+00 8.4167365137e-06 -5.2839414021e-04 3.1933933902e-06 2020049045946.618 3995.7122228524 450.4220212004 5246.0851015862 -0.0547273015 7.7821571464 -0.5335448290 3.2786164149e-04 -2.1515298085e-02 1.4185498420e+00 9.4832961713e-06 -6.2416198312e-04 3.6081375877e-06 2020049050046.618 3982.5467942771 915.8522781185 5201.0819191117 -0.3838307864 7.7258060518 -0.9657974479 3.0048093228e-04 -2.0634691467e-02 1.4240267915e+00 1.0418230377e-05 -7.1791799704e-04 4.0716284109e-06 2020049050146.618 3949.7037449032 1376.7581450812 5130.3026640366 -0.7103735730 7.6314316921 -1.3923880559 2.7635957704e-04 -1.9824497136e-02 1.4294176624e+00 1.1238213557e-05 -8.0930472936e-04 4.5751943653e-06 2020049050246.618 3897.3859479376 1830.8761341194 5034.1512933668 -1.0327190651 7.4996667269 -1.8111843232 2.5538044853e-04 -1.9090875187e-02 1.4347316193e+00 1.1955846145e-05 -8.9756260252e-04 5.1089327231e-06

Definition

Please note that since no frame is specified for the Generic On-Orbit Ephemeris format states, we only accept files that have states in an EME2000 like frame. The covariance frame will be read out of the header. Additionally, all units are assumed to be in kilometers and kilometers/second. A full definition of the Generic Ob-Orbit Ephemeris format can be found on the Space Track website here.

Modified ITC Ephemeris Format (.txt)

Example

created:2020-02-18T05:00:16Z ephemeris_start:2020-02-18T04:58:46Z ephemeris_stop:2020-02-19T12:58:46Z step_size:60.000000 ephemeris_source:jspoc_ephemeris_source_propagation UVW 2020049045846.618 3989.0958732016 -17.2373703241 5265.0373968349 0.2752851297 7.8000537922 -0.0977985834 3.5860219464e-04 -2.2459784351e-02 1.4129779994e+00 8.4167365137e-06 -5.2839414021e-04 3.1933933902e-06 2.6268298658e-05 -1.6526046363e-03 6.1799949546e-07 1.9328702078e-06 -3.2421125799e-07 2.0311480490e-05 -7.6171792542e-09 -2.3755862633e-08 2.9319743229e-10 6.3664794854e-08 -4.0059858664e-06 4.1330213084e-09 4.6853629625e-09 -5.7585787077e-11 2.1766937508e-11 2020049045946.618 3995.7122228524 450.4220212004 5246.0851015862 -0.0547273015 7.7821571464 -0.5335448290 3.2786164149e-04 -2.1515298085e-02 1.4185498420e+00 9.4832961713e-06 -6.2416198312e-04 3.6081375877e-06 2.5148139319e-05 -1.6581006192e-03 7.2955926402e-07 1.9381050806e-06 -3.1424962881e-07 2.0633410476e-05 -9.1000118116e-09 -2.4117531346e-08 3.0130184400e-10 6.0114941916e-08 -3.9643594592e-06 4.7286747971e-09 4.6338247833e-09 -5.7662841633e-11 2.1022875463e-11 2020049050046.618 3982.5467942771 915.8522781185 5201.0819191117 -0.3838307864 7.7258060518 -0.9657974479 3.0048093228e-04 -2.0634691467e-02 1.4240267915e+00 1.0418230377e-05 -7.1791799704e-04 4.0716284109e-06 2.4103180091e-05 -1.6634237365e-03 8.3860394519e-07 1.9430670357e-06 -3.0483859177e-07 2.0951267506e-05 -1.0583542826e-08 -2.4473185485e-08 3.0938788356e-10 5.6527964825e-08 -3.9020314102e-06 5.2424026597e-09 4.5580160018e-09 -5.7408483348e-11 2.0118354532e-11 2020049050146.618 3949.7037449032 1376.7581450812 5130.3026640366 -0.7103735730 7.6314316921 -1.3923880559 2.7635957704e-04 -1.9824497136e-02 1.4294176624e+00 1.1238213557e-05 -8.0930472936e-04 4.5751943653e-06 2.3141068512e-05 -1.6685886863e-03 9.4471291993e-07 1.9477786402e-06 -2.9605050797e-07 2.1260353985e-05 -1.2057854096e-08 -2.4817386247e-08 3.1731038193e-10 5.2955164916e-08 -3.8193295254e-06 5.6643841695e-09 4.4583862562e-09 -5.6805163996e-11 1.9072030948e-11 2020049050246.618 3897.3859479376 1830.8761341194 5034.1512933668 -1.0327190651 7.4996667269 -1.8111843232 2.5538044853e-04 -1.9090875187e-02 1.4347316193e+00 1.1955846145e-05 -8.9756260252e-04 5.1089327231e-06 2.2268969229e-05 -1.6736104800e-03 1.0469992310e-06 1.9522626988e-06 -2.8796752379e-07 2.1556117955e-05 -1.3505749089e-08 -2.5144882896e-08 3.2492256002e-10 4.9439684734e-08 -3.7167015178e-06 5.9855410390e-09 4.3355268734e-09 -5.5839638630e-11 1.7905382505e-11

Definition

Please note that since no frame is specified for the Modified ITC Ephemeris format states, we only accept files that have states in an EME2000 like frame. The covariance frame will be read out of the header. Additionally, all units are assumed to be in kilometers and kilometers/second. A full definition of the Modified ITC Ephemeris format can be found on the Space Track website here.

Two-Line Element Set Format (TLE)

TLE files with or without the title line are accepted. Please note that we do not accept TLEs for the Operational Ephemeris endpoint. All three of the following are examples of accepted TLEs.

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.