[TUHS] In Memoriam: J.F.Ossanna

Paul Winalski paul.winalski at gmail.com
Thu Nov 29 03:08:17 AEST 2018

On 11/27/18, Ken Thompson via TUHS <tuhs at minnie.tuhs.org> wrote:
> another joe:
> echo 1 was a 100 foot balloon that was
> launched into space  in the early 60s. this
> was the first satellite that was easily visible
> to the naked eye.
> joe wrote a set of fortran programs that
> tracked the orbit of echo and calculated
> the direction to look from a point on earth.
> to do this, he had to learn fortran and
> orbital dynamics.
> by the time i came to bell labs (1966) the
> program, azel, for azimuth/elevation, was
> expanded to track planets, moons, satellites,
> etc. moreover, it tracked the shadow of the
> earth cast by the sun (night). it could predict
> within a few seconds when echo would wink
> on or off as it passed through the shadow.
> a version of azel was maintained all the time
> i was at bell labs. we used it to predict
> eclipses, transits, occultations etc. when
> we first got a voice synthesizer, the day's
> predictions were spoken at 5pm in case
> there was anything interesting.
What a great story.  There is today a website (heavens-above.com) that
does the same thing as Joe's azel.  Amateur Astronomers visit it
regularly to get the night's predictions for visible satellite
transits, visible passes of the International Space Station, etc.  I
had no idea the idea went back that far.

-Paul W.

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