Two-Line-Elements (TLEs) are elements with which the computer calculates the position of the satellite

e.g.:

ISS (ZARYA)

important! here is the fractal date of exposition (350th day of the year 00 + 0.144...days)

1 25544U 98067A 00350.14419977 .00030044 00000-0 30061-3 0 3819

2 25544 51.5748 300.5578 0007608 230.6191 129.4120 15.65274025118289

The TLEs for ISS should be younger than 1 day !

The other satellites are not as critical because they do not often correct the track.