Hank (and the -bb)
Attached is the spreadsheet previously mentioned spreadsheet to fix TLEs
checksums. I've rewritten it since what I was using was still a tedious
operation and I didn't want to distribute that to the community. This
should be much better, though you still need to remove any leading
spaces in the lines.
It appears that O/OREOS' TLEs on their website are OK now, possibly
because SpaceTrack is publishing now. My apologies for not getting this
out sooner; we'll have to wait for the next launch to try this out.
During the fog-of-war in the days after launch, I find there are often
multiple TLEs for the same satellite. In this case I like to change the
IDs so I can have them all loaded in GPredict simultaneously. This
spreadsheet will verify that the IDs are the same for both lines, and of
course regenerate the checksums.
This spreadsheet was created with OpenOffice 3.2.1, and I've exported it
to Excel and checked it with MS Office XP and appears to work fine.
Please let me know if there are any problems.
Happy holidays and 73,
Ryan KB1LKI
On 11/30/10 11:33 AM, PA3GUO wrote:
Hi Ryan
Thanks a lot for your detailed reply.
Would you be so kind to share that spreadsheet (XLS?) with me ?
In the coming days I really need (well, would higly appreciate) to
have working TLEs - especially also for Nanosail.
Best of course would be if the O/OREOS/Nanasail team could fix this prior
to posting them on the web :-)
Thanks
Henk
---- Ryan Caron<rca...@gmail.com> schreef:
The O/OREOS TLEs consistently do not have valid checksums (last digit of
each line). I submitted a comment about this on their website but I have
not heard back. The correct checksums are 2& 3, and not the 6& 5 that
is listed.
If, by the time you read this, the posted TLEs are not 6& 5, then the
TLEs have been updated and you'll have to generate new checksums. The
formula is a sum of all numerical characters on the line, including the
line number, treating minus signs as a one and everything else (letters,
+, spaces) as a 0. Then take modulus 10 of the sum (i.e. last digit of
the sum). Look it up on wikipedia for more details.
I've made a spreadsheet to fix this, but it is still a manual operation
for me (got to write a script at some point). Some programs disregard
the the checksum, which is why HRD& the website still work and your
tracking tool doesn't. Predict/GPredict, my tools of choice, require
valid checksums, making proper TLEs a pet peeve of mine. I don't know
what NOVA's up to.
In terms of "swarm spread" (i.e. how small delta-V between spacecraft
that shared the same ride, which in this case is just done by compressed
springs, translates into spatial differences), 35 minutes of separation
is pretty high for just 10 days after launch. With all the latest TLEs
from the three websites, I show O/OREOS being 3.5 minutes ahead of RAX,
and RAX being a 1.33 minutes ahead of FAST1/2.
Ryan, KB1LKI
On 11/30/10 4:54 AM, amsat-bb-requ...@amsat.org wrote:
------------------------------
Message: 4
Date: Mon, 29 Nov 2010 22:55:16 +0100
From: PA3GUO<pa3...@upcmail.nl>
Subject: [amsat-bb] O/OREOS TLE errors ?
To:amsat-bb@amsat.org
Message-ID:<19767175.1291067716437.javamail.r...@viefep21.chello.at>
Content-Type: text/plain; charset=utf-8
Dear all,
I keep on having troubles with the O/OREOS kepler sets.
RAX and the others are fine.
With todays version (as from the O/OREOS dashboard on the web)
- NOVA gives O/OREOS just a bit behind RAX
- HamRadioDeluxe give O/OREOS 35 minutes behind RAX
- The O/OREOS web (dashboard graphic) shows O/OREOS 35 minutes behind RAX
- My private antenna tracking tool does not recognize the keplerset of O/OREOS
Anyone else has experienced this (and maybe even a solution) ?
Henk
--
Henk, PA3GUO
--
Henk, PA3GUO
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