Celestia Forums

Question: Noted that while tracking the International Space Station (ISS) the position and orbit did not match that from the NASA real time tracking site. What can be done to match the actual position/orbit.

Joe Willie

The standard ssc orbit for the ISS that comes with celestia is shockingly innacurate...

Heres what to do to get the very latest correct elements:

1. Goto http://www.celestrak.com , go to the current data page, and click ISS.
2. Copy the two lines of figures under the line saying "ISS Zarya"
It currently reads:

3. Download grant hutchinson's TLE- ssc converter (You'll find it on the addons forum)
4. Input those 2 lines into the converter
5. save the resulting output as an ssc file, into celestia's extras folder.
6. Now you should have an object orbiting the earth called "1998-067A" which is the designator for the ISS. This is what you should be tracking

Alternatively, you could just get a astronomy program which directly accepts TLE orbits... But celestia is better so dont

Alternatively Jack...you could post the ssc for us?

Guest wrote:Alternatively Jack...you could post the ssc for us?

Well ok so



But don't forget that the ISS's orbit changes regularly, it doesn't stay static forever... In other words if it's supposed to fly over on a certain night, you'll need to get updated elements that day to make sure you know when to look up...

You need to know how to do it yourself, because people won't be posting updated elements every time they change on celestrak... (which is every single day)

Slightly off-topic, but possibly of interest to ISS observers:

A few weeks ago I did an ISS "marathon", in which I observed the ISS pass overhead on five consecutive orbits. It was fun to do, although I didn't get much sleep that night!

Five consecutive sighting opportunities seems fairly common, although I doubt that very many people have made the effort to do it. I'm unsure if six consecutive sightings is ever possible.

- Hank

Thanks Jack...that ssc request was from me. Not logged in again. Thanks for that. I probably won't do a daily 'fix' on this orbit. I want time to actually enjoy the views. Call me old fashioned...

Hank...I admire your curiosity. Where did you find the time?

Regards...bh. Now..where's that ESB.