Alan Pickup's SatEvo Page

Satellite tracking and decay information

2008 January 21: New version of SatEvo (v0.51) available

2008 January 28: Missing DLL fix (see readme in download)


What is SatEvo?

SatEvo is my program to compute the decay or re-entry times of earth satellites. For objects nearing decay, it generates sets of orbital elements for each revolution. The format of the input and output element sets conform to the standard tle format accepted by many prediction programs.

Current elements

Up-to-date orbital elements (elsets) are important for accurate predictions during the final weeks, days and hours of a satellite's life; a small percentage change in the drag experienced by such an object can make it run early or late by several minutes after only a few days. This can make observations of near-decay objects all the more challenging, though the sight of a low satellite, perhaps below 200 km in height, can be most impressive - it may be considerably brighter because of its reduced range, and it may be zipping along at a startling rate.

For some years I provided frequently-updated files of orbital elements in these pages. I am no longer able to do this. Instead, elsets are available by registering with Space-Track.

Download SatEvo here...

Version 0.51 of SatEvo was made available for download on 2008 January 21. Among other changes, this allows the user to specify the prevailing F10.7 solar flux (see readme file in the zip) and it corrects a bug in the reading of epochs in 2008 and 2009. A UNIX Solaris version is no longer provided; instead, a Linux version is available.

Each .zip file contains the appropriate SatEvo.exe program and a readme.

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Last Updated: 2008 January 28