Question Why publish TLE?

[SiberianTiger]

I have a question that may seem strange. I recently found myself wondering, why do NORAD publish their satellite tracking data at all? AFAIK, no other entity in the world does the same. Is it a kind of requirement according to the American law?

And also, how long ago did they begin publishing, and in which form did TLE's come firstly?

 

[Urwumpe]

1. NORAD does the worldwide coordination of space debris tracking. They use observation data which also others (like for example the Europeans) provide. If you have the best tracking network in the world, it is easy to become program lead.

2. TLEs are formatted for being "stamped into punch cards" - be read by the then-standard IBM mainframes in 80 character records. Just like good old RINEX, which also uses the 80 character record width. Remember TLE and RINEX standards are at least 20 years older than the current XML madness...

Also, the Space Shuttle software also has such "virtual punch cards" on the magnetic master tapes, these control how the System/4Pi software is compiled from the test version into the actual flight software.

 

[SiberianTiger]

1. NORAD does the worldwide coordination of space debris tracking. They use observation data which also others (like for example the Europeans) provide. If you have the best tracking network in the world, it is easy to become program lead.

Ok, so it's a kind of an international agreement? Which one is that, then?

I understand why the TLE's are TLE's. But the Celestrack.com website hasn't been there from the beginning of Everything. How did they distribute the TLE's before the www flourished? Were they available in Apollo era already?

 

[Urwumpe]

NORAD Provides the data since 1957, but the public catalog in TLE format was made by NASA when they started to compile it from the NORAD catalog. Can't say when this happened though, was pretty much before Apollo.

 

[SiberianTiger]

Well, back in 1957 there was no much space debris to track. Does anyone happen to know, why NORAD are disclosing their data since that time?

 

[Urwumpe]

Well, back in 1957 there was no much space debris to track. Does anyone happen to know, why NORAD are disclosing their data since that time?

Out of a very simple reason - they have it and it helps preventing the third world war if everybody is aware of what is a satellite and what not.

 

[SiberianTiger]

I still don't consider this reason convincing enough. Who are the 'everybody' so that them having this knowledge would prevent a nuke war? American USAF command could just supply the satellite data to every interested allied agency. But they did more and published them for the world's use. Why?

 

[insanity]

My best bets:
Because the published satellites have no strategic value. It is data that any government could probably obtain anyways.

Being the only people to publish this data gives the entire world a subtle reminder that America is still top-dog.

It is useful data to a small percentage of people who have an interest in such things, and as it has no real strategic value (after all, much of what is in space are "public goods" like Hubble and the ISS) it could probably be obtained under FOIA anyways.

I imagine it has to do with some combination of all three. The only real use of the data for most people is that it can tell you if something cool is overhead. We can't shoot it down and the people that could already have the data (hell most of them are our partners in space). So there is really no reason not to publish them.

 

[SiberianTiger]

It is useful data to a small percentage of people who have an interest in such things, and as it has no real strategic value (after all, much of what is in space are "public goods" like Hubble and the ISS) it could probably be obtained under FOIA anyways.

Okay, so perhaps FOIA is the keyword. To add some possible reason into the basket, there also may be a presence of space geeks within NORAD who initiated publishing the data back in 50's, plain good will and solidified tradition.

I am summing all it up trying to understand why Russian Space Control Centre publishes nothing. Probably because we have no tracking stations at equatorial latitudes worldwide, hence the data cannot be as full as from the DSN. Another reason is because nobody ordered so.

---------- Post added at 01:19 ---------- Previous post was at 00:35 ----------

BTW, I suddenly realize what's the mess with Nauru. :lol:

 

[Voyager_VI]

Maybe because...

http://en.wikipedia.org/wiki/Registration_Convention

The register is kept by the United Nations Office for Outer Space Affairs (UNOOSA) and includes[5]

• Name of launching State
• An appropriate designator of the space object or its registration number
• Date and territory or location of launch
• Basic orbital parameters (Nodal period, Inclination, Apogee and Perigee)
• General function of the space object

My guess is that providing the TLE database aids all parties involved.

 

[David413]

Keep in mind too, NORAD doesn't publish TLE's for all space objects. Most "omissions" are for various intelligence-gathering satellites. I regularly receive TLE's for these "spy-sats" via folks who track them for a hobby. But the actual (or, "official") sources exclude these items. And, to receive TLE's since 9/11, Spacetrak requires a user to register. But, using their extensive catalog of past TLE's, I'm just about finished creating a new STS Expansion pack series of the past Hubble missions using real world elements. As an American taxpayer, I "own" these too!

 

[SiberianTiger]

http://en.wikipedia.org/wiki/Registration_Convention

The register is kept by the United Nations Office for Outer Space Affairs (UNOOSA) and includes[5]

Thank you, but that's a thing different from NORAD's catalogue of space objects.