Kurt Jonckheere (
Tue, 21 Jan 1997 23:55:58 +0100

Hello Leo,

In your message you bring up some ideas, a number of people have been  
thinking about last years, but haven't find the time to do it.
I'm happy that you finally find some time to do it !

I suppose that one of your wishes for 1997 was to do a lot of work on/with
the PPAS and I see you allready are on your way...

>observations are from satellites that have already decayed
or have been Steady during their whole life.

The PPAS approach has always been the following : put everything that was
received into the PPAS and let the PPAS *user* decide what he wants to use
and what to filter out.
As the name indicates, its main goal was to collect timings of flash periods,
not observations of steady rockets, not more detailed observations like DRA.
Of course things have evolved last years, e.g. leading to a DRA-input format.

>2. PPAS clean-up
>For some time I have been thinking about a PPAS clean-up and started  this in
>december 1996.
I should call it "reorganisation" i.s.o. clean-up.

>The goals of this clean-up are:
>a) Split the PPAS data base in two parts; one containing all the observations of
>the satellites still in orbit, 
>the other part containing all observations of decayed satellites, the
>b) Working through the first part and checking which satellites, not observed
>for long, should be observed as soon as possible;
I had this idea some years ago, especially to check e.g. GTOs and related once,
because the PPAS contains a number of old observations of these type with
eccentric orbits, which have not been observed recently.  Due to lack of time I
didn't really went into it...
Fortenately some observers are already checking these old and not so easy
to observe (with binoculars) objects.  Mike McCants for instance observed
some of them last years, which are now added to the PROGRAM.ROB

The idea to do it in a structured way is good one...

>c) Doing a) and b) I've and shall come to (minor) faults in the PPAS files

>b) With Satflash I've printed as far as possible the Flash Period Graphs of all
>satellites in the PPAS files and started with printing the 5 most recent
huge job...

>c) Collecting the (minor) faults, such as wrong Cospar ID (satellite and/or
>fragment doesn't exist in the Noradcataloge), wrong date (mostly the year),  ect.
>I'll report to Kurt Jonckheere for correcting them in the upcoming PPAS7

>3. The PPAS ORBIT program
>I'm willing to coordinate and maintain the PPAS  Observe on a Regular Basis In
>Time program 
>ORBIT updates will be posted to SeeSat-L regulary as well as the resulting
>observations by either Kurt in his PPAS updates or by me.
A year ago, there was the idea to do this together with the checking on 
Accelerations.  Now, the things I do (with accelerations) are done 
"semi-automatically".  This means
that I have a number of small tools which I run in sequence, but unfortenately
they still need checking from the "operator"...

We have to find a way to move your and my work together.

Maybe one easy way to perform the checking of "not yet decayed and not recently
observed objects" is by adding them in the Program.rob with a new code, e.g. 'C',
meaning 'to be Checked'.
There exists (another) small tool to filter the elements with this code from an 
element file or prediction file form Patrick Wils' Sat.

>Cospar ID	numb	Last obs	Period	Days since
>		obs	date			last obs
>59-  1 B 	3	5-08-91		22,52	1997
>61- 18 A 	475	24-02-96	148	333
>61- 28 A 	136	30-04-96	45,9	267
What software are you using ? (please answer this in a private mail).

>In the last column are listed the days since the last observation untill the actual
>systemdate of the computer; they can be updated automatically every time the
>file is opened and the actual daynumber has changed.
It may be possible to use this file to update the PROGRAM.ROB with the Cospar
ID of the objects that have to be Checked (code 'C').

>Any comments may be posted on SeeSat-L or directly to my own e-mail adress.
Please post your comments to Seesat-L, because more people will be interested in 
them (as I am).  Of course detailed discussion about software-implementation can
be done in a smaller group.


Kurt Jonckheere