Celestia Forums

Posted: **30.07.2002, 08:07**

If anyone is interested I compiled info for 3 of the GOES weather satellites. They are kind of neat to watch since they are geostationary. Give you an idea of what a geostationary orbit is like. I just used the mars global survey mesh since I couldn't find one for the GOES satellites.

"GOES-8" "Sol/Earth"
{
Class "spacecraft"
Mesh "marsglobalsurvr.3ds"
Radius 0.015

EllipticalOrbit {
Period 0.99722222
SemiMajorAxis 42168.7768
Eccentricity 0.00061147
Inclination 0.12350146
AscendingNode 94.1357978
ArgOfPericenter 38.26969545
MeanAnomaly 272.2256238
Epoch 2452478
}

Albedo 0.10
}

"GOES-9" "Sol/Earth"
{
Class "spacecraft"
Mesh "marsglobalsurvr.3ds"
Radius 0.015

EllipticalOrbit {
Period 0.99722222
SemiMajorAxis 42168.7783
Eccentricity 0.00043252
Inclination 0.55100614
AscendingNode 94.6692340
ArgOfPericenter 187.24691160
MeanAnomaly 155.3342049
Epoch 2451442
}

Albedo 0.10
}

"GOES-10" "Sol/Earth"
{
Class "spacecraft"
Mesh "marsglobalsurvr.3ds"
Radius 0.015

EllipticalOrbit {
Period 0.99722222
SemiMajorAxis 42168.1708
Eccentricity 0.00026029
Inclination 0.37521474
AscendingNode 279.99653040
ArgOfPericenter 238.14188920
MeanAnomaly 96.44867919
Epoch 2452477.75
}

Albedo 0.10
}

Posted: **22.08.2002, 22:07**

It's nice that people are still making satelites

Mike M.

Posted: **23.08.2002, 17:23**

One of my favorite Celestia addons is Thomas Guilpain's .ssc with the GlobalStar and Iridium communications satellites:

Get constellations.zip from http://bruckner.homelinux.net/addons.html

Lots of satellites!

--Chris

Posted: **23.08.2002, 19:22**

Hey stevenabors, thanks
Quick Question:

I put in your text info, into the extra folder and named it WeatherSatalites.ssc. and its seems to work great.

BUT.. (I dont know much about space stuff) they seem very far away for satalites.

they look to be about half way between the earth and the moon
on a syncronus orbit with earth, (Looks great)

Are they really this far away from earth :?:

Posted: **23.08.2002, 23:09**

chris wrote:One of my favorite Celestia addons is Thomas Guilpain's .ssc with the GlobalStar and Iridium communications satellites:

Get constellations.zip from http://bruckner.homelinux.net/addons.html

Lots of satellites!

--Chris

When he says lots, he means LOTS! There must have been at least a thousand in there! It crashed celestia everytime I went to earth.

Mike M.

Posted: **23.08.2002, 23:33**

Darkmiss wrote:they look to be about half way between the earth and the moon
on a syncronus orbit with earth, (Looks great)
Are they really this far away from earth

Ought not to be 1/2 way, not quite !
There are (approx.) 2 types of Weather satellites, the GOES and Meteosat ones belong to the geostationary class (as stevenabors said). So yes, they are quite far out, 36000 km These give a 'regional' or 'continental' view of weather patterns
The other broad class are the 'polar orbiters' such as Noaa-14 etc. which are in a 100 minute sun-synchronous orbit (about 850km). These give a 'close-up' view of the cloud cover ie. more detailed local coverage.

Posted: **23.08.2002, 23:44**

I wrote:they are quite far out, 36000 km

I ought to have said "they are quite far out, about 36,000 km above the earth"
Sorry for my inexactitude

Posted: **24.08.2002, 12:39**

Hmm mine are 42143.510 km from earth

didnt think it was right

any idea why, :?:

im really not that clued up on space matters
or sofware codeing :roll:

where in the ssc file can i change something to set it right :?:

Which on eof these means the distance from its orbiting planet :?:

Period 0.99722222
SemiMajorAxis 42168.7768
Eccentricity 0.00061147
Inclination 0.12350146
AscendingNode 94.1357978
ArgOfPericenter 38.26969545
MeanAnomaly 272.2256238
Epoch 2452478

sorry for being such a noob ( but we all are sometimes )

Posted: **24.08.2002, 15:30**

Darkmiss actually you don't have anything to change as your satellite is correctly set at a distance of 36000 km (35700 exactly) above the "surface" of the Earth whereas the SemiMajorAxis is the distance to the centre of the Earth. So when you add 6370 km (for the radius of the Earth) to your satellite's altitude you get a SMA equals to more or less 42700 km.

Posted: **24.08.2002, 20:41**

Well okay then, thank you

Told you I was new to all this star stuff
just love to look at the planets and all else in orbit around them

Okay ill get me coat...... :lol:

Posted: **24.08.2002, 21:06**

Darkmiss wrote:Okay ill get me coat......

hey, no, dont do that, dont you mean your spacesuit ? It's cold out there ! ;-)

sorry for being such a noob ( but we all are sometimes )

No, no prob, it was all my fault ! I should have been clearer about 36000.
Later (in bed!) thinking, "I should have tied that in to the semi-major axis in the .ssc "
But thanks to anonymouse, I see it has all been cleared up now,,

Ok, I'll go get my sackcloth and ashes ,,, :oops: