Celestia Forums

OK, I know we do. But our stars are very gentle stars: just spheres with textures or - if you have installed an extension - flares.

But real stars aren't so gentle, especially if they are giants. Let me show you what I mean. Here is an image from a numerical simulation of a giant like Betelgeuse:

http://www.aip.de/~mst/pub_files/images ... 0086_E.gif

It doesn't look like anything we have in Celestia. But let's check these movies (all of them are relatively short, usually a few MBs):

http://www.astro.uu.se/~bf/movie/dst35g ... movie.html

Here is a direct link to one of these movies:

http://www.astro.uu.se/~bf/movie/dst35g ... _I3blm.mpg

Amazing, isn't it? Just a few years, what a difference in a shape of the star! Remember that what you see is the star, which diameter is comparable to a Jupiter orbit!

But watch this movie:

http://www.astro.uu.se/~bf/movie/dst35g ... bubble.mpg

Or this one, where you can see the density fluctuations in a red giant (so you can see the changes of the star's surface):

http://www.astro.uu.se/~bf/movie/dst35g ... 26_rho.mpg

It's obvious that huge stars aren't spherical. They are unregular and they dramatically change their shapes!

Is it possible to restore the real nature of huge stars in Celestia? You know, I'm not a developer, but maybe it's possible to use a few spheres moving around a center in a semi-chaotic way, with smart textures or something like this?

This does not impress me until you quote respective (refereed) scientific publications where the underlying physics is precisely discussed.

My first priority as a theoretical physicist is NOT to admire some colorful video sequences, but rather to critically examine the assumptions underlying these movies. Only then can one judge whether the videos make any sense!

Bye Fridger

t00fri, I'm not a movie fan, but a science journalist and physicist. I do not share meaningless links.

Most of these movies are made by or in cooperation with such kind of organizations like Institute for Astronomy and Space Physics (Uppsala University) or Astrophysical Institute in Potsdam. You can check these results, you can find sources and related works. If it's not enough for you, you can check direct images of Betelgeuse surface. They were made by a few observatories (like HST) and you can see things like huge dark spots on the surface.

I think it's enough to talk about this phenomenon on this forum.

And if you really want scientific papers, please check this link:

http://www.aip.de/groups/sternphysik/st ... t_neu.html

edit:

Examples of direct observations of Betelgeuse are here:

http://www.aavso.org/vstar/vsots/1200.shtml

Sources inside.

edit2:

Direct link to SCIENTIFIC paper related to movies from my first post:

http://www.aip.de/groups/sternphysik/st ... ag_prt.pdf

s3nn0c wrote:t00fri, I'm not a movie fan, but a science journalist and physicist. I do not share meaningless links.

Good. But don't forget that you missed to tell us initially...Also, movies without specification of the underlying physics resources are just useless as a basis for serious discussions.

And if you really want scientific papers, please check this link:

http://www.aip.de/groups/sternphysik/st ... t_neu.html

Yes, thank you. That's all that's relevant for me at least. I'll have a look.

Bye Fridger

Seems there is some more work to deal with after the implementation of wavelenght filters...

s3nn0c wrote:t00fri, I'm not a movie fan, but a science journalist and physicist...

BTW, it would be nice to have this in your profile!