Subject: 5-Digit Satellite Catalog Number (aka NORAD ID) will soon become 6-Digits
From: Husson, Van (PERATON) <vhusson@peraton.com>

Author(s): Van S Husson, Robert Sherwood

The 5-Digit Satellite Catalog Number, formerly known as the NORAD Id, has been projected to run out in July/August 2026. After 69999 has been assigned, any new cataloged objects will have 6-digits. The Legacy Two-Line Element (TLE) Data Format can`t accommodate a 6-digit object. In May 2020, to overcome this constraint Celes Trak implemented a CSV TLE data format. 

Also, in 2020, Space Track Org started to provide orbital elements in the CCSDS Orbit Mean-Element Message (OMM) format, which can handle 9-digit object numbers. The CCSDS OMMs are available in Extensible Markup Language (XML), JavaScript Object Notation (JSON), and Keyword Value Notation (KVN) format.

Since the ILRS CPF and CRD formats are free format with spaces between entries, no changes to these formats are necessary.

However; stations or other users that have software which converts Legacy TLE Data into CPFs will require software modifications to support new 6-digit objects. In addition, stations that have software 
that assumes the Satellite Catalog Number is a 5-digit integer will require modifications to accommodate new 6-digit objects.

Any questions and/or concerns can be addressed to the ILRS Central Bureau.