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Path: utzoo!watmath!clyde!bonnie!akgua!sol1!s170
From: s170@sol1.UUCP (s170)
Newsgroups: net.ham-radio,net.columbia
Subject: Re: Challenger orbital elements
Message-ID: <201@sol1.UUCP>
Date: Sun, 30-Sep-84 20:42:00 EDT
Article-I.D.: sol1.201
Posted: Sun Sep 30 20:42:00 1984
Date-Received: Mon, 1-Oct-84 05:07:05 EDT
References: <164@mouton.UUCP>
Organization: THE SOLUTION, Lincoln, NE
Lines: 45

> Here is a predicted element set for orbit 23 of the upcoming Challenger
> mission. Note, however, that it was based on an October 1 launch and needs
> to have its RA (right ascension) of the ascending node adjusted for the
> actual launch time, which I believe is currently scheduled for October 4.
> 
> Epoch time:      84276.85138889
>    Tue Oct  2 20:26:00.0   1984 UTC
> Inclination:       57.2007 deg
> RA of node:        68.7538 deg
> Eccentricity:    0.0010544
> Arg of perigee:   346.2766 deg
> Mean anomaly:      14.1415 deg
> Mean motion:   15.97849766 rev/day
> Decay rate:          0.046 rev/day^2 [incredibly high! -- prk]
> Epoch rev:              23
> Semi major axis:  6658.131 km
> Anom period:     90.121113 min
> Apogee:            287.857 km
> Perigee:           273.816 km
> Ref perigee:      2466.84893045
>    Tue Oct  2 20:22:27.590 1984 UTC
> 
> The high inclination of this mission will make the orbiter visible at much
> higher latitudes than most shuttle missions. It will also make it possible
> for more amateurs to receive the 435 mhz transmissions of a Getaway Special
> experiment that will be mounted in the cargo bay.  Tracking the shuttle,
> however, has always proven to be extremely difficult due to the unpredictable
> drag effects of the low orbit and the constant perturbations of maneuvering
> rockets. As we found with STS-9, predictions made from element sets which
> were only a day old could be off by minutes.
> 
> Phil Karn

*** REPLACE THIS LINE WITH YOUR MESSAGE ***


In reference to the orbital element state-vector, does someone have an
easily transportable algorithm (or program, even) that will give longitude/
latitude predictions, visibility/altazimuth, etc?  I know I'm asking a lot,
but it sure would be neat.  I know the ham elements out there must have some
such thing, but I haven't subscribed to QST in some time, now.  Anybody seen
anything like it?  I have a PC-compatible, Turbo Pascal, and even (choke, gag!)
MS Basic.
   Thanx for listening (reading?).
         Russ Schnapp (...akgua!sol1!s170)