Two Line Elements and Metadata Xpaths

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For Polar-orbiting satellites At metadata section: Platform Info > Platform Orbit > Keplerian Orbit

Homepage for NORAD TLE

Platform Orbit Elements TLE Row TLE Column TLE Description Notes
/Ephemeris/sngdate/caldate > Single Calendar Date 1 19-23 Epoch (Day of the year) Convert Day-of-Year to YYYYMMDD
/Ephemeris/sngdate/time > Single Date Time 1 24-32 Epoch (fractional portion of the day) Convert Fraction-of-Day to HHMMSS
/kepleror/orbitpd/orpdunit > Orbit Period Units n/a 'minutes'
/kepleror/orbitpd/orpdval > Orbit Period Value 2 53-63 Mean Motion (Revs per day) conversion equation: (24/MM)*60)
/kepleror/eccentry > Eccentricity 2 27-33 Eccentricity (decimal point assumed) Add decimal to front of number
/kepleror/orbangun > Orbit Angle Units n/a 'Degrees'
/kepleror/inclinat > Inclinations 2 09-16 Inclination (degrees)
/kepleror/raascnod > Right Ascension of Ascending Node 2 18-25 Right Ascension of the Ascending Node (Degrees)
/kepleror/argupgee > Argument of Perigee 2 35-42 Argument of Perigee (degrees)
/kepleror/peripass > Perigee Passage Time n/a in TLE 'Unknown' (for now)

Line 1 of TLE
TLE Column TLE Description Metadata Xpath
01 Line Number of Element Data
03-07 Satellite Number
08 Classification (U=Unclassified)
10-11 International Designator (Last two digits of launch year)  
12-14 International Designator (Launch number of the year)  
15-17 International Designator (Piece of the launch)  
19-20 Epoch Year (Last two digits of year) /metadata/platinfo/platforb/Ephemeris/sngdate/caldate: YYYY
21-32 Epoch (Day of the year and fractional portion of the day) /metadata/platinfo/platforb/Ephemeris/sngdate/caldate: MM
/metadata/platinfo/platforb/Ephemeris/sngdate/time: HHMMSS
34-43 First Time Derivative of the Mean Motion
45-52 Second Time Derivative of Mean Motion
54-61 BSTAR drag term (decimal point assumed)
63 Ephemeris type
65-68 Element number
69 Checksum (Modulo 10)

Line 2 of TLE
Column Description Metadata
01 Line Number of Element Data
03-07 Satellite Number
09-16 Inclination (Degrees) /metadata/platinfo/platforb/kepleror/inclinat
18-25 Right Ascension of the Ascending Node (Degrees) /metadata/platinfo/platforb/kepleror/raascnod
27-33 Eccentricity (decimal point assumed) /metadata/platinfo/platforb/kepleror/eccentry
(add decimal to front of number)
35-42 Argument of Perigee (degrees) /metadata/platinfo/platforb/kepleror/argupgee
44-51 Mean Anomaly (degrees)
53-63 Mean Motion (Revs per day)
64-68 Revolution number at epoch (Revs)
69 Checksum (Modulo 10)