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Re: What are "Charlie" elements? - unclassified



Peter - 

You'll find usageof the 1-line "Charlie" element sets in
military circles and (more
rarely) with other LEO systems. 

Enjoy!

Eric W3DQ
Washington, DC
w3dq@amsat.org

--------------


=======================
One Line Element Format
=======================

The One Line Element (OLE) format is a somewhat abbreviated set
of data
used by the Navy at the Naval Research Laboratory (and perhaps
others). 
Some useful information which is included in the 2-Line Element
format is 
omitted, such as the Revolution Number at Epoch. Other
information, such 
as the International Designator, can often be obtained from
other sources 
using the satellite number (NORAD catalog number). The only
virtue to this 
format is its brevity.

         1         2         3         4         5         6
123456789012345678901234567890123456789012345678901234567890
nnnnnyydddffffffddddddiiiiiinnnnnneeeeeeaaaaaammmmmmxxxxxxxx
206399019071772000014705251829684400765901146334880715202450

Columns  1-5   NORAD catalog number
Columns  6-7   year
Columns  8-10  day number
Columns 11-16  fraction of a day
Columns 17-22  drag term  (Implied decimal left)
Columns 23-28  inclination  (Implied decimal in the middle)
Columns 29-34  ascending node  (Implied decimal in the middle)
Columns 35-40  eccentricity  (Implied decimal left)
Columns 41-46  argument of perigee  (Implied decimal in the middle)
Columns 47-52  mean anomaly  (Implied decimal in the middle)
Columns 53-60  mean motion  (Implied decimal 2 from the left)

Example:

206399019071772000014705251829684400765901146334880715202450

The following values are obtained:

20639         catalog number
   90         year
  190         day number
     .717720  fraction of a day
     .000147  drag term
   52.518     inclination
  296.844     ascending node
     .007659  eccentricity
  011.463     argument of perigee
  348.807     mean anomaly
   15.202450  mean motion

The input of elements in this form may be terminated by a line which
contains a zero for the catalog number.

One-Line Element format information courtesy Mike McCants.

----------------------


At 10:35 12-05-98 +1000, you wrote:
>
>
>I asked this wise group a while ago, and got no reply.
>Here goes again...
>
>What are "Charle" elements?
>
>It appears from the contaxt that they are a one-line version of NORAD
>Two-Line Elements. That probably makes them like 'state vectors'.
>
>(1) Can anyone give me an example of a "Charle" element set
(even better:
>related to a corresponding set of TLEs), and give me a decode of the
>numbers in the "Charlie" set (what the numbers mean).
>
>(2) Where can I find that information on the Net?
>
>Thanks,
>     _  .      Peter R. Ellis, Amateur Radio Op. VK1KEP
>   _-' |_|\         at Canberra, Australian Capital Territory
>  /        \        email: peter.ellis@dao.defence.gov.au
>  \_.--._ C/
>         \/         RNARS Australia #1528 (see also
http://come.to/rnars/)
>          v
>VK1KEP:   http://www.geocities.com/CapeCanaveral/5796/vk1kep.htm
>Mine:
http://www.geocities.com/CapeCanaveral/5796/pre-pers.htm
>
>
>
>



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