Advanced Question Two-Line Elements

[StargazerBranden]

Okay, math whizzes out in Orbiterland. This is for you. I have been working on setting up my own scenarios for shuttle fleet. Well, let me rephrase that. I have been attempting to set up my own scenarios for shuttle fleet but have some questions regarding orbits. I have TLE sets for ISS and Mir but have some conversion questions on how to take the data and input it in orbiter so that I have a true and accurate representation of the stations orbit at a given time. For example:
Mir
1 16609U 86017A 98197.13016538 0.00008762 00000-0 90218-4 0 6359
2 16609 51.6578 260.0079 0006650 226.7644 133.2778 15.65731574708592

Here is Mirs orbit on 16 Jul 1998 03:07:26.

Question 1: Is the RA of Ascending Node (260.0079) the value I use for Longitude of Ascending Node?

Question 2: How do I calculate Semi-Major Axis?

Question 3: How do I calculate the Mean Longitude at Epoch variable?

 

[GLS]

Okay, math whizzes out in Orbiterland. This is for you. I have been working on setting up my own scenarios for shuttle fleet. Well, let me rephrase that. I have been attempting to set up my own scenarios for shuttle fleet but have some questions regarding orbits. I have TLE sets for ISS and Mir but have some conversion questions on how to take the data and input it in orbiter so that I have a true and accurate representation of the stations orbit at a given time. For example:
Mir
1 16609U 86017A 98197.13016538 0.00008762 00000-0 90218-4 0 6359
2 16609 51.6578 260.0079 0006650 226.7644 133.2778 15.65731574708592

Here is Mirs orbit on 16 Jul 1998 03:07:26.

Question 1: Is the RA of Ascending Node (260.0079) the value I use for Longitude of Ascending Node?

Question 2: How do I calculate Semi-Major Axis?

Question 3: How do I calculate the Mean Longitude at Epoch variable?

ScenarioEditorTLE takes a TLE file and puts the vessel where it should be. Not sure how precise it is because of leap-seconds and such. :shrug:

 

[StargazerBranden]

Wow! Thanks a bunch! It never dawned on me to check orbit hangar. Thanks for that. You, sir, are a steely-eyed missile man!

 

[SolarLiner]

I've wrote a converter to orbiter scenario: [ame="http://www.orbithangar.com/searchid.php?ID=6850"]TLE Scenario Generator[/ame]

For maximum accuracy the scenario's date needs to be set to the TLE's epoch, given how Orbiter interpolates orbital data.

 

[boogabooga]

The use of TLEs comes up from time to time on Orbiter Forum. They seem to be a source of confusion. It is not as simple as plugging in orbital elements. I recommend ajaja's [ame="http://www.orbithangar.com/searchid.php?ID=2617"]Scenario Editor TLE[/ame] because it uses the proper NORAD SGP4/SDP4 propegation that the TLEs are intended for.

Please see this thread and especially post 27:
http://www.orbiter-forum.com/showthread.php?p=506757&postcount=27