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Constellation deformations

Posted: 23.11.2007, 14:53
by Imy
Can Celestia show contellation deformations due to star movements on a long period as a hundred thousand years?

Thanks in advance.

Posted: 23.11.2007, 15:25
by BobHegwood
Just try it...

Check the constellation you're interested in, then hit the L key a few
times to increase the speed of time. You'll be able to watch any
deformation as it occurs. :wink:

Thanks, Brain-Dead

Posted: 23.11.2007, 15:42
by selden
Unfortunately, Celestia does not currently implement proper motion: except for the orbits of stars that are in multiple star systems, the stars will not move across the sky, no matter how long you wait :(

In principle, the code that implements star orbits could be used to show proper motion, but that hasn't been done yet. Nobody has created an Addon to show it, for example.

Posted: 23.11.2007, 15:46
by BobHegwood
Sorry Selden...

Is news to me. Of course most everything is news to me nowadays.
:wink:

As always, thanks for your help.

Posted: 24.11.2007, 09:05
by Imy
Thanks. So no solution to see deformations.

Posted: 24.11.2007, 09:49
by t00fri
Imy wrote:Thanks. So no solution to see deformations.


It depends HOW you are looking at the deformations! Remember the fact that many things are "relative" in physics ;-)

As Selden wrote, Celestia does not include proper motions of it's stars while the observer is stationary...(mainly also for reasons of display speed)

But you may beautifully observe the deformations of the constellations while travelling at ~2-3 ly/sec through the Universe!

Start at Earth, switch on constellations and then hit F7 (speed :1 ly/sec) and crank it slowly up to 2.5 ly/sec by subsequently pressing the 'a' key. Watch the deformations of the constellation lines as you travel.

Bye Fridger

Posted: 26.11.2007, 13:38
by Imy
Indeed, I've already seen theses deformations when the observer is moving and is going in a large view to see all milky way frame and that's why I've wondered why these deformations don't appear due to the clock changing.
Moving stars could probably increases CPU usage and Celestia already uses a lot. But I think that when you 're watching so large time period you haven't to refresh each year. This reason could be a tip to move star without using a lot CPU. Refreshing a group of star each after another, according their distance, each Thousand years for instance, would not be so important for CPU, wouldn't be?