Sixth black hole in production

[Cham]

Maybe I'm obssessed with black holes

Here's a preview of the last one, derived from the fifth black hole I've made (Black Naught) :




Now, I'm having a small naming scheme problem. I wanted all black holes to have a name like "Black ...", so they can be easily accessed in Celestia. How should I call this one ? I tried "Black Navel", but, well, ... Someone has a better idea ? Right now, the names I used are "Black Ogre", "Black Pit", ""Black? EGO", "Black? Widow", "Black Naught".

[Dollan]

Black Charybdis?

Black Abyss?

Black Eye? No, maybe not that one....

...John...

[Cham]

I like Black Abyss. Thanks.

Here's another preview of the new accretion disk, with a background nebula :

[TourqeGlare]

WOW!

[Juan Marino]

Hello, Cham:

Sixth black hole in production, very good!!, but...

You can put new black hole around star HD 226868?:

Sixth (or seventh) black hole = Cygnus X-1 ( non-fictitious black hole around of the star HD 226868)

Sorry for my bad english... (I am Spanish-speaking)

[Cham]

Juan,

do you have more details on the orbital parameters of this real black hole ? Distance from its star and orbital period ?

Edit : Hmm, according to some web pages I've found, the orbital period is 5.6 days. From Kepler's third law, the mean distance between the star and its black hole should be (approx) 0.19 AU, if the star has a mass around 20 solar mass and the black hole around 8 solar mass. This is fine, as my black hole is ... 8 solar mass !!

[Cham]

Okay, this will be Cygnus X-1. I still have some work to do on the accretion disk. Live in Celestia, the movements are really hypnotic. Lots of differential roation here.

[Cham]

Well, now I need some crittics. Here's a link to the addon in its current state. Can someone test it and tell his opinion ? It is a 10.4 MB zipped file.

http://nho.ohn.free.fr/celestia/Cham/CygnusX-1.zip

Oh, and try it in full screen mode, without any information showing in the corners. Pretty.

[selden]

There seem to be two sets of files in the zip archive. One set is in /CygnusX-1/ and another is in /_MACOSX/CygnusX-1/.

It looks like all or most the files in /_MACOSX/ have names that start with an underscore, and when they exist, they seem to be smaller than the corresponding files in the other directory tree. Not all of the files in /CygnusX-1/ have equivalents in /_MACOSX/CygnusX-1/, though. Also, /_MACOSX/CygnusX-1/_HD226868.ssc seems to contain binary gibberish rather than text. There aren't any other catalogs in that directory.

I'm guessing that these might be related to how the files are stored on a system running MacOS, which is different from how they're stored on Windows and Linux systems. They'll cause quite a bit of confusion for novices.


I'm getting about 12fps on this system:

512MB 2.4GHz P4; WinXP Pro, SP2
128MB FX 5200; ForceWare v66.81
Celestia v1.4.0p6 @ 1600x1200

Cygnus-X1 looks great!

[Cham]

Thanks Selden.

The OS X folder with strange files can be erased.

12 fps ? Hmmm. I'm getting about 19 fps on my system, and I'm not satisfied with that. I'm trying to reduce the number of curved models to reduce the fps hit, but this is hard.

[Cham]

I tried to mimic the behavior of light around a black hole. Happily, I was able to do it ! Here's a partial explanation (the gif pictures are coming from this web page : http://luth2.obspm.fr/~luminet/chap10.html ).

Because of the very strong gravitational field close to the black hole, light is moving on some curved paths, NOT on straight lines, like on this picture below :


When looking down to a black hole, it should appears a bit like on this picture :


Now, here's the effect I was able to achieve on my black hole. Okay, it's not perfect, butthe idea is there. The red parts are strongly red shifted. This is the gravitational redshift predicted from General Relativity :


From some distance, it looks like this (Celestia has a small depth sorting problem here, which isn't bad)
:

I have updated the zip file on the link above, so it's the latest version of the addon.

[Juan Marino]

Hello, Cham:

I found an article with PARAMETERS FOR THE SYSTEM CYG X-1/HDE 226868 (TABLE 1):

THE ASTROPHYSICAL JOURNAL, 510:874891, 1999 January 10

Orbital period (days)... 5.59974 (Cyg X-1)
Major axis (R)... 26.3 (Cyg X-1) 14.6 (HD 226868)
Separation (R)... 26.3 + 14.6 = 41

Thanks.
Marino wrote.

[Cham]

Major axis (R)... 26.3 (Cyg X-1) 14.6 (HD 226868)
Separation (R)... 26.3 + 14.6 = 41
[/size][/b]

What units are these ? According to what I've found, separation should be rougly 0.2 AU.

I recall that my addon is available right now at this link :

http://nho.ohn.free.fr/celestia/Cham/CygnusX-1.zip

[Spaceman Spiff]

Hi Cham,

It's OK, the values are in Solar Radii. 40.9Rsun is very close to 0.2A.U.

Spiff.

[Fightspit]

When I see the Black Abyss, I have noticed a red point near it.



Finaly, I saw a (fictional ?) planet or asteroid maybe...
What is it




Bye !

[Cham]

When I see the Black Abyss, I have noticed a red point near it.

[img=http://img19.imageshack.us/img19/2040/blob02jw.th.png]

Finaly, I saw a (fictional ?) planet or asteroid maybe...
What is it



Bye !

Well, that's the first "easter egg". The last one is harder to find, but the object is bigger.

And be cautious to not falling into the black hole !

[Juan Marino]

Hi Cham...

Only...... THANKS!!!! for Cham and Cygnus X-1

Marino wrote.

[Juan Marino]

Hello,

Finaly, I saw a (fictional ?) planet or asteroid maybe...
What is it

.....moon-planet maybe?

Thanks,
Marino wrote

[Spaceman Spiff]

Well, that's the first "easter egg".

Nice work, Cham, it even looks like it's made of chocolate! And the black hole Add-Ons are very lovely too.

Spiff.

[fsgregs]

Cham:

Holy Crap! This is your best work yet. It is spectacular!!! The detail in the accretion disk is ... well ... GOSH!

My only question is whether you ever figured out why your nebula disappear at a distance of more than 1 LY. Many other nebula in Celestia add-ons do not and can be seen from hundreds of LY out. Is it the way the add-on is set up???

Anyway, thank you for this. I will be incorporating it into two of my Educational Activities, which are currently undergoing their summer rewrites.

P/S/ - Tibet is an interesting place. I suspect Budda would choose to reside inside a Black Hole. It certainly is a pathway into the universe

Regards,

Frank