NASA's J-Pass/J-Track java-based Satellite tracking program

Robert Bloch (
Thu, 6 May 1999 18:27:32 -0400

Howdy Folks!

Saw a link to NASA's J-Pass/J-Track java-based program in my mail box and
thought it would be of interest to the group.

I first thought it would be another one of those silly java windows with the
toy object floating across the window, but I tweedled with it for a few minutes
to get all the settings correct, and it seemed to be pretty functional. 

It quickly generated a list of what appeared to be around 75-100 satellites
scheduled to pass or be visible at diverse magnitudes in my location for 24
hours. The list appeared to include both LEO and GEO orbitors displayed neatly
on a 24 hour time-chart. Pass(es) were indicated on the timeline with colored
blocks. When the blocks are clicked on they display a re-sizable sky chart
complete with the projected track of the bird, and it also has function buttons
to show the progression of the pass. I discovered that a left or right click of
the mouse inside the field of the sky chart also gave me a ALT/AZ reading. The
sky chart window also included an estimated visible Magnitude although it
appears to have a problem.

I have yet to test it against the night sky, but for those of you out there who
can't afford tracking software or are in a pinch for time it might be worth
checking J-Pass out. It might be very useful.

 Look up as much as you can!


Robert Bloch
30.311359 N -81.396865W
Neptune Beach, Florida, USA

``An expert is an oridinary fellow from another town". -J. Vernon McGee