Atmosphere Data

The place to discuss creating, porting and modifying Celestia's source code.
Topic author
AlexChan
Posts: 33
Joined: 29.09.2004
With us: 20 years 1 month

Atmosphere Data

Post #1by AlexChan » 17.05.2005, 08:03

In solarsys.ssc, the data of The Earth's atmoshpere is 60 kilometers
Is is too thin? I searched some website,
The Earth's atmosphere thickness is about 1000 kilometers.
Shall we change the data to be more accurate?

And anyone have the moons' amtoshpere data of our solar system?
I just know Europa, Ganymede, Callisto, Enceladus and Triton have a thin atmosphere, anymore?

Avatar
t00fri
Developer
Posts: 8772
Joined: 29.03.2002
Age: 22
With us: 22 years 7 months
Location: Hamburg, Germany

Re: Atmosphere Data

Post #2by t00fri » 17.05.2005, 08:38

AlexChan wrote:In solarsys.ssc, the data of The Earth's atmoshpere is 60 kilometers
Is is too thin? I searched some website,
The Earth's atmosphere thickness is about 1000 kilometers.
Shall we change the data to be more accurate?

And anyone have the moons' amtoshpere data of our solar system?
I just know Europa, Ganymede, Callisto, Enceladus and Triton have a thin atmosphere, anymore?


Oh God, NO. The atmosphere has a continuous density distribution as function of altitude. It certainly does not drop to zero at a particular, well-defined point. So there are clearly various definitions of the altitude of an atmosphere in terms of the density ratio, cpmpared to the planet's surface. Celestia has a much too primitive way of displaying atmospheres for any more sophisticated such definitions. While there may still be molecules of air out to 1000km, most of the air is "gone" around 60 km of altitude.

Bye Fridger

Avatar
PlutonianEmpire M
Posts: 1374
Joined: 09.09.2004
Age: 40
With us: 20 years 2 months
Location: MinneSNOWta
Contact:

Post #3by PlutonianEmpire » 17.05.2005, 08:48

Really? I heard it was mostly "gone" at around 62 km, instead of 60 km...

I could be wrong though...
Terraformed Pluto: Now with New Horizons maps! :D

Topic author
AlexChan
Posts: 33
Joined: 29.09.2004
With us: 20 years 1 month

Re: Atmosphere Data

Post #4by AlexChan » 17.05.2005, 08:51

t00fri wrote:
AlexChan wrote:In solarsys.ssc, the data of The Earth's atmoshpere is 60 kilometers
Is is too thin? I searched some website,
The Earth's atmosphere thickness is about 1000 kilometers.
Shall we change the data to be more accurate?

And anyone have the moons' amtoshpere data of our solar system?
I just know Europa, Ganymede, Callisto, Enceladus and Triton have a thin atmosphere, anymore?

Oh God, NO. The atmosphere has a continuous density distribution as function of altitude. It certainly does not drop to zero at a particular, well-defined point. So there are clearly various definitions of the altitude of an atmosphere in terms of the density ratio, cpmpared to the planet's surface. Celestia has a much too primitive way of displaying atmospheres for any more sophisticated such definitions. While there may still be molecules of air out to 1000km, most of the air is "gone" around 60 km of altitude.

Bye Fridger


Oh, I understand now! Thanks for telling!

Avatar
t00fri
Developer
Posts: 8772
Joined: 29.03.2002
Age: 22
With us: 22 years 7 months
Location: Hamburg, Germany

Post #5by t00fri » 17.05.2005, 08:55

PlutonianEmpire wrote:Really? I heard it was mostly "gone" at around 62 km, instead of 60 km...

I could be wrong though...


I certainly wouldn't argue about a +-1/60 = +-1.7 % effect ;-)

Again, the definitions of where to apply the "cut" may vary slightly.

Bye Fridger

Avatar
PlutonianEmpire M
Posts: 1374
Joined: 09.09.2004
Age: 40
With us: 20 years 2 months
Location: MinneSNOWta
Contact:

Post #6by PlutonianEmpire » 17.05.2005, 08:57

Oh, alrighty. Thanks!

:)
Terraformed Pluto: Now with New Horizons maps! :D


Return to “Development”