Software Edition Information

The SGP4/SDP4 implementations are available in three editions: Public, Standard, and Professional.

The Public Edition is true to the original NORAD implementation.  It is available on this website for immediate download.  This version of the software is for non-commercial use only; commercial users must obtain either the Standard Edition or the Professional Edition.

The Standard Edition is identical to the Public Edition, except it also includes support for WGS-84 and the ECF coordinate system.  Intended for commercial use, a license fee is required (contact the author for more information).

The Professional Edition is similar to the Standard Edition, but also incorporates the changes recommended in "Revisiting Space Track Report #3".  This edition of the software provides the next level of accuracy and reliability for the most demanding tracking applications.  Intended for commercial use, a license fee is required (contact the author for more information.)  Professional Edition license holders may also purchase the optional Track Library. 

*Implements "Revisiting Space Track Report #3" recommendations.