Feature Request: breaking the 16KLY barrier

General discussion about Celestia that doesn't fit into other forums.
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selden
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Feature Request: breaking the 16KLY barrier

Post #1by selden » 04.02.2008, 22:02

I think it's becoming more appropriate for Celestia to be able to display stars well beyond its current 16KLY limit.

In December, the Hayden Planetarium released an update to its 3D Digital Universe (based on PartiView) which shows 1 million halo stars from the Sloan Digital Sky Survey. Granted, it uses their spectrographic distances, which aren't as accurate as GAIA's parallax measurements will be, but it's a start.

http://haydenplanetarium.org/universe/update/
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Post #2by chris » 04.02.2008, 22:25

I have in mind a scheme for doing this . . .

Each star would maintains a pointer to its containing octree node. Instead of storing the star position relative to the universe origin, the star's position is actually an offset relative to the node center. This would permit Celestia to continue using low-precision but compact single-precision floating point values for star positions. It may be practical to use 16-bit integer coordinates for even smaller stars.

--Chris

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Post #3by ajtribick » 05.02.2008, 00:01

This is definitely a feature worth pursuing. At present it is not possible to depict the host stars of planets detected through microlensing.

In addition, there are a couple of extragalactic eclipsing binaries which would be very nice to be able to implement.

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Post #4by t00fri » 05.02.2008, 06:48

What else, at the scientific level I mean?

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Post #5by selden » 05.02.2008, 13:03

t00fri wrote:What else, at the scientific level I mean?

F.


most pulsars

most globular clusters (as clusters of Stars, not as DSC models)

most Cepheid variables

Suparnovae

The stars orbiting the Black Hole at the Milky Way's center
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Post #6by buggs_moran » 05.02.2008, 13:38

selden wrote:The stars orbiting the Black Hole at the Milky Way's center


Ohh, that would be really cool to visualize.

And I would add active galactic nuclei to that list.
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Post #7by tech2000 » 05.02.2008, 14:51

Fridger,

don't you have any good ideas how to change this so that it at the same time lays the foundation for your Cosmological Visualization Project ?

Bye, Anders

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Post #8by t00fri » 05.02.2008, 20:02

tech2000 wrote:Fridger,

don't you have any good ideas how to change this so that it at the same time lays the foundation for your Cosmological Visualization Project ?

Bye, Anders


Anders,

I think Chris' proposal for going beyond the 16kly barrier sounds good. For Cosmology, the "pointlike objects" are NOT stars but entire galaxies! In other words, the relevant distance scales are so much larger that individual stars loose their meaning entirely...

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Post #9by Mikael » 06.02.2008, 08:58

I've thought about other software I've used in the far past which could calculate probabilities of a certain configuration of planets and moons at a particular star or stars, and then showed that most likely one.

I think it could make it a lot more interesting at least if at least made this an option for those who would like to view how universe might look like further out there.

Just because the scientists haven't been able to see it doesn't mean it's completely empty out there! :wink:

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Post #10by selden » 06.02.2008, 12:42

Mikael,

Fictional/hypothetical information is best provided in the form of an Addon, which can be created by anyone.
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Post #11by Reiko » 09.02.2008, 21:02

Will this mean I can put stars in other galaxies?

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Post #12by LordFerret » 10.02.2008, 05:14

Reiko wrote:Will this mean I can put stars in other galaxies?

I've wondered about the possibility of that also.

I'm a bit out of my league here, but... what about Celestia, finding itself "in" another galaxy, being able to load and handle a new dataset (stars.dat) for that galaxy, handling addressing just as it does currently? Like, moving the origin (temporarily), using code overlays or paging or something along those lines? Yes, I realize all the data for such a galaxy would be fictitious (and therefore classified to be an 'addon')... I'm just thinking in terms of all the fictional work done thusfar for Celestia, and how this might be applied.

Too far a stretch?

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Post #13by Mikael » 10.02.2008, 16:40

And even if it would be "fictional" could it be implemented in a more "intelligent" way, i.e. the known stars could have planets, moons and other objects based on what we *know* about the stars! :idea:

That would certainly still be fictional but worth the time to create an add-on for, if it's possible.
"Who are we? We find that we live on an insignificant planet of a humdrum star lost in a galaxy tucked away in some forgotten corner of a universe in which there are far more galaxies than people." -- Carl Sagan


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