Rings (disks) around stars?

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john71
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Rings (disks) around stars?

Post #1by john71 » 26.07.2017, 07:35

Is it possible to have rings (disks) around stars in Celestia?

If it is possible, how can it be achieved?

As I know rings can only be used with planets and moons...

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selden
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Post #2by selden » 26.07.2017, 09:03

Unfortunately, not directly.

Celestia has several problems when trying to draw something like that. For example, it doesn't illuminate properly an object which surrounds the light source.

As I recall, the workaround is to use multiple SSC objects following one another in the same orbit.
Selden

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john71
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Post #3by john71 » 27.07.2017, 05:35

Thanks for the info! Yes, I use multiple ssc objects for this purpose but there are strange flashes on the screen as the viewpoint moves. The two objects are in some kind of graphic conflict with each other it seems...

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Cham M
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Post #4by Cham » 27.07.2017, 14:11

Well, even if disks around stars aren't illuminated by the star, in Celestia, you still could make great looking disks with sprites, that feel very natural.

Just to show off what you can do in Celestia, here are a couple of models I did, several years ago.
Many of these models are still available on the forum, while some have a broken link (do a search).

In random order :
Attachments
dust1.jpg
bh1.jpg
bet2.jpg
apoc.jpg
accDisk2.jpg
Last edited by Cham on 27.07.2017, 14:16, edited 2 times in total.
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Cham M
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Post #5by Cham » 27.07.2017, 14:12

Since I'm restricted to only 5 pictures per post, here five more views :
Attachments
im6.jpg
im5.jpg
im4.jpg
exp11.jpg
im3.jpg
Last edited by Cham on 27.07.2017, 14:17, edited 1 time in total.
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Cham M
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Post #6by Cham » 27.07.2017, 14:15

And 5 others :

Added after 5 minutes 37 seconds:
All these models were made using a mathematical software (Mathematica, Maple, etc...) to generate the random coordinates of all the sprites.

Here's an example for you to play with. A disk around Fomalhaut :
Fomalhaut.zip
(2.82 MiB) Downloaded 82 times
(3 MB zip file)

This is an old model made from a combination of two parts : a weak sprites model, and a texture on a smooth mesh. The effect is pretty from some angles, but not that convincing as seen from inside the disk. You can use the parts to make your own version around other stars, if you wish.

Have fun !
Attachments
Trou Noir M31.png
storm2.jpg
Proto2.jpg
Proto1.jpg
im7.jpg
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FarGetaNik M
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Post #7by FarGetaNik » 27.07.2017, 15:50

Impressive! I wish default Celestia would include some sprite models.

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john71
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Post #8by john71 » 27.07.2017, 16:17

Thanks Cham, very nice!

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Cham M
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Post #9by Cham » 27.07.2017, 16:41

Here, just for your pleasure, I publish these old disk models, around HIP 114189/HR 8799, HR 4796 A and Vega :

disks_models.zip
(2.09 MiB) Downloaded 94 times
(2.2 MB zip file)

Do wathever you want with their parts. It's free for Celestia users.

EDIT : And while I'm at it, why not this other small addon :
HD_141569.zip
(12.3 MiB) Downloaded 89 times
(12.9 MB zip file)
"Well! I've often seen a cat without a grin", thought Alice; "but a grin without a cat! It's the most curious thing I ever saw in all my life!"

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john71
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Post #10by john71 » 27.07.2017, 19:32

Excellent, thanks! :clap:

dani3ls
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Post #11by dani3ls » 28.07.2017, 14:42

Cool! You should create a motion illusion with gifs. !

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SVision M
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Post #12by SVision » 18.08.2017, 09:47

Super :clap: ! Perhaps I'll take Your models to create your own add-ons.

themartian
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Post #13by themartian » 19.08.2017, 04:42

you can also activate the emissive true code so you only have to make 1 object

valverie F
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Post #14by valverie » 30.08.2017, 08:29

Cham,
this is so beautiful, wow
I'm new here, hi :)

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Fenerit M
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Post #15by Fenerit » 31.08.2017, 19:09

I still have the Cham's protostar NGC404; if it has been loss somewhere in the net, I could upload it again.

valverie wrote:I'm new here, hi :)

Welcom to Celestia Forums! :smoke:
Never at rest.
Massimo

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Post #16by valverie » 17.09.2017, 14:05

yay!
smoking kills tho :silenced:

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Fenerit M
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Post #17by Fenerit » 17.09.2017, 22:37

Never mind: I've quit smoking time ago. That emoticon mean "peace and calm" for me.
Never at rest.
Massimo

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Diigg M
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Post #18by Diigg » 19.09.2017, 12:53

Hello, how do I install these addons?
I have put the corresponding folders in the Celestia extras folder, but they are not displayed as in your images.
Last edited by Diigg on 19.09.2017, 19:17, edited 1 time in total.

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Cham M
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Post #19by Cham » 19.09.2017, 14:22

Diigg, you need to go to the star's location to see the addons !

Look into the stc file (using a text editor) to identify the star you want to visit, and type its name into Celestia's console.

For example, type "Fomalhaut" or "HD 141569" in Celestia, and view them.
"Well! I've often seen a cat without a grin", thought Alice; "but a grin without a cat! It's the most curious thing I ever saw in all my life!"

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Askaniy M
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Post #20by Askaniy » 23.09.2017, 11:04

Cham, it looks great! Can you make a gifs using these screenshots?


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