Read Two-Line Element Ephemeris Files

Satellite ephemeris data is published regularly in "two-line element" or TLE files. Each satellite listed in the file has a header line consisting of its name, plus two lines of coded text containing its most recently observed orbital parameters. Although the format is well defined, it is not always easy for a human to extract the orbital information from the encoded text. This short, self-contained MATLAB function reads each entry in a TLE file and converts the information to a more human-friendly form. A checksum is performed over each entry to insure that the data has not been corrupted. The function includes an optional argument for providing a list of satellite catalog numbers. This enables searching a large TLE file for specific vehicles of interest.
Current ephemeris files can be downloaded from https://www.celestrak.com/NORAD/elements/.