Re: Bright sat list / software

JAY RESPLER (jrespler@InJersey.com)
Wed, 18 Dec 1996 00:23:26 -0500 (EST)

On Mon, 16 Dec 1996, Robert Sheaffer wrote:
> > > So, rather than *the program* telling me what satellites will be
> > > visible from my location, I have to tell *it* which ones I might
> > > want to observe.
> > 
> > I don't know what the problem is here.  I thought Leo did a good job in saying
> > that, exactly as you want, THE PROGRAM tells you what is visible.  
> 
> The program will tell me what's visible IF I tell it in advance which
> satellites I want to observe.

 If you want to know what is potentially visible, you do not have to choose any
sats at all.  Just use any element set and you'll get a list of everything in
the sky.

 
> I should thank that the program, given a correct elements file, could
> tell me "what's up there" 

That is just what is does.  No problem there.

>without any guidance beyond that of brightness
> and elevation. Why is a separate satellite list REQUIRED?

Do you realize that an element file has NO indication of brightness?  You can
use it for elevation.  A separate list is required if you want some indication
of brightness.
 
> What if there's a bright satellite that I don't know about, but might
> be visible anyway?

If what you're looking for are bright naked eye sats, use VISUAL.TLE for your
elements list.  That's why I made the list.   It includes virtually all sats
brighter than mag 3.8.  Even if you're not aware of some bright sat, it should
show up when you make predictions using VISUAL.TLE.

> What if something new got launched, and I didn't
> update my list?

Read SeeSat-L.  You'll find out about new bright sats.  You can then wait till I
update VISUAL.TLE, or get those new elements and put them into your master list
yourself.
 

> > This is one thing that everyone has to do for him/her self.  No program is so
> > smart that it will know a new sat is launched and add it to its base list.
> 
> But people are ALREADY DOING this in constructing the elements list.
> Now, given that we ALREADY HAVE the elements list, why is it necessary
> for many people to duplicate the effort by maintaining an up-to-date
> list of satellites?

See above.  You don't have to update your list if you want to use VISUAL.TLE,
unless you don't want to wait for me to do the update.

> >   I
> > look at new launches and decide which I want to look for.  I don't expect
> > software to decide that for me.
> 
> I have no problem with running a "short list" of satellites sometimes
> (I do that, too) so long as you can also run a "complete list".

There is no reason you can't do both.

> > Almost no sats are visible all the time.  They drift in/out of view.  That is
> > something the software accounts for. You don't have to keep abreast of those
> > changes or update lists for that.  The program does it for you.
> 
> ONLY if you already put the satellite on your list of ones that you want to
> observe.

If you don't want to add to your list, make predictions using ELxxx.tle.  That
has virtually all payloads and rockets (about 4000 objects).  Of course, you
will GREATLY increase your computing time.   You will also get such a long list
of predictions that you probably won't be able to pick out what to look for.
That's why we all make shorter lists of potential objects to look for.
But if that's what you want,  it is available.  Have fun.
 

> > > > > Given that we're working from a list of continuously-updated satellite
> > > elements that are presumably quite correct, but out software
> > > fails to rely upon that information, this is *still* a
> > > "cart-before-the-horse" approach. It would be fine to have a
> > > "list of favorite satellites" mode of operation, so long as
> > > you ALSO have a "show me everything brighter than Magnitude X"
> > > mode.

You CAN do that.  See above.

> > What program are you using?  

You didn't answer that yet.


> > My software will do either one. And, using Word Perfect, I can get a combined
> > list of both!
> 
> So, you need to go into your word processor to duplicate the work that
> Ted Molczan and others have already done in compiling the elements
> list.

That's NOT what I said.  I'm not combining element lists.  I'm taking 2
different sets of PREDICTIONS, made with different control  files,
with different criteria, and combining and sorting them  by time into 1 list of
predictions.
Again, I don't know of any program that will do that.



Jay Respler
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               JRespler@InJersey.com
    Satellite Tracker * Early Typewriter Collector
               Freehold, New Jersey