Parameters 

Description 

TLEstr [string/cell] 

Two or three-line TLE or the location of the space-track.org satellite catalog. 

SearchList [string/scalar] 

(Optional) If a string, returns all TLE (3-line only) where the satellite names begins with SearchString. If a number, returns all TLEs (2 or 3-line) where the satellite number is SearchString. Only used if TLEstr is a TLE catalog file name or directory location 

Return Values 

Description 

tle [struct] 

Structure containing the TLE data - sorted by SSC 

tle.SSC [string] 

Space Surveillance Catalog Number 

tle.INTERNATIONAL_DESIGNATOR [string] 

International designator. First two characters designate the launch year; the next 3 characters indicate the launch number, starting from the beginning of the year; the remainder of the characters (1 to 3 characters) indicate the piece of the launch. 

tle.EPOCH_DATE [vector] 

Epoch date of the element set in the form [YYYY MO DD HH MM SS.xxxx] 

tle.MEAN_MOTION_DOT [scalar] 

1st derivative of the mean motion with respect to time 

tle.MEAN_MOTION_DOT_DOT [scalar] 

2nd derivative of the mean motion with respect to time 

tle.BSTAR [scalar] 

B* drag term 

tle.ELEMENT_NUMBER [scalar] 

Element number 

tle.INCLINATION [scalar] 

Orbit inclination (deg) 

tle.RIGHT_ASCENSION_OF_NODE [scalar] 

Right ascension of ascending node (deg) 

tle.ECCENTRICITY [scalar] 

Orbit eccentricity 

tle.ARGUMENT_OF_PERIGEE [scalar] 

Argument of perigee (deg) 

tle.MEAN_ANOMOLY [scalar] 

Mean anomaly (deg) 

tle.MEAN_MOTION [scalar] 

Mean motion (rev/day) 

tle.EPOCH_REV [scalar] 

Revolution number at epoch 

tle.CLASSIFICATION [string] 

Classification of element set 

tle.TLE [string] 

The two or three line element set 

tleMessage [string] 

Notice of either

• Satellite number mismatch between lines
• Internal summation doesn't agree with TLE

checksum value Either flag is a good indicator that the TLE isn't valid, but both are very rare