Well, it looks like I was a little too late to find the 3D model of Achernar
![](/images/smilies/happy.gif)
. I have been on Thanksgiving vacation for a few days, followed up by a few final exams so I have not been able to look for or post any information in a while. The first thing that I noticed when I opened this thread was your image of the oblated stars: another excellent job. The new oblated stars look amazing, and I like the attention to detail with the circumstellar disks around stars with high rotation periods. I am glad to see that everything has worked out for you.
In reply to your previous message, I can understand why you would not want to place objects with orbital periods greater than 400 years into orbit in your simulation. However, I think you should leave those objects in the simulation regardless. To substitute the loss of orbital movement, maybe the orbital period can be displayed within the current data of the object in the simulation. Also, just like how you did in your video of Iota Draconis b, display the actual orbit of the object to give the user an idea of just how long the object would have to travel in order to move across the screen... let alone complete one orbit. This will hopefully give the user the idea that the object will not noticably move in the simulation, while giving them an idea of just how large those orbits actually are.
On the subject of large orbits, this idea came to mind. Might it be possible to include the stars and their respective orbits which revolve around the supermassive black hole in Sgr A*? This came to mind, because few weeks ago we learned about the star S2 which has an orbital period of about 15 years, but a semimajor axis of about 950 AU!
Here is an example from YouTube of the many stars around Sgr A*
http://www.youtube.com/watch?v=nyY7waPQT4k I believe S2 is the innermost star.
Here's an animation of a supermassive black hole in an elliptical galaxy:
http://www.youtube.com/watch?v=pBT3RZ-RZCw&NR
I love the supermassive black hole that you have created, but might it be possible to lengthen the jet streams and flare out and expand the accretion disk to give the black hole a much more massive appearance similar to the animation?
For binary star systems, I have been trying to find out how one can calculate the volumes and radii of a star system's Roche lobes, and how to calculate the Langragian points, as well. I am only an astronomy undergraduate, and we haven't learned this information yet. Do you mind explaining how one would find that information? I don't know if this sort of calculus can be implemented into your simulation, but if it could, it would allow for accurate models of semidetached and contact binaries. Here are some models that I have found:
![](http://www.physics.sfasu.edu/astro/binstar/BluePair2.GIF)
Constuction of GW Cep
![](http://www.physics.sfasu.edu/astro/binstar/gwcep.gif)
GW Cep
![](http://www.physics.sfasu.edu/astro/binstar/XYLeo-LongHiRes.gif)
XY Leo
http://wonka.physics.ncsu.edu/~blondin/Movies/algol.mpg
A really nice animation of Algol. More videos like this illustrating the physics of accretion disks and mass transfer can be found here
http://wonka.physics.ncsu.edu/~blondin/Movies
I also found this program...
http://www.binarymaker.com It is not exactly free (US $100.00), but it seems like a program ideal for the creation of the various types of binary systems.
Nevertheless, here are some sample models that can be found on the website:
http://caleb.eastern.edu/binary_type_definitions.php
The Catalog and AtLas of Eclipsing Binaries can be found here:
http://caleb.eastern.edu/choose_star_view.php
EDIT: [ It looks like I completely missed something very important on that website. This link
http://caleb.eastern.edu/choose_star_view.php shows you all 305 stars in the catalog, but after clicking on one of the stars there should be the words
Library Sets. Clicking on any of the sets sends you to a page with light-curve information and graphs, radial velocity data, but most importantly, a model of the binary system. There are currently 305 models that have been made already on the website.]
EDIT 2: [ Well, it looks like I found something better, for it's FREE. This is the original website that I was trying to look for, and here it is
http://www.midnightkite.com/binstar.html This is where I found those 3D model GIFs in my unedited post. There is a lot to offer here. There are PDFs on the calculus behind contructing eclipsing binary models, and how to model stars based on their rotation speed and other tangible properties (this could be used to check if any approximations that were made in contructing the oblated stars were correct). There are .xls spreadsheets on Roche Lobes and Langrangian points, but most importantly, the StarLight Pro program. By downloading the program the user can construct their own models based on stellar data, but it also allows the user to view over 300 3D rotating models. By clicking the "Extra" tab, the user can save the 3D model as an image or an animation, adjust the inclination of the system, etc. The "Help" tab features parameter details such as Roche lobe radii, etc. There are also more hyperlinks in the website I gave you which contain more information and programs that might be of assistance, such as Alexander Hobbes' Binary View. This program is like StarLight Pro, but it allows the user to view the axis of rotation of the binary system, and stars are created through particles instead of grids and dots. The problem that I have with this program, however, is that the animation seems to be stretched horizontally as the coordinate grid should be a perfect square and not a rectangle, any adjustment of the animation window will permanently distort the animation until the program is restarted, and you cannot save the images or animations. Other than that, there are many catalogs regarding eclipsing binaries and other interesting information on the website.
![](http://forum.thegamecreators.com/xt/xt_apollo_pic.php?i=1062867)
Attached is a GIF of Algol that I created with StarLight Pro with the Stefan-Boltzmann feature unchecked. I used Irfanview to convert the images into GIFs and UnFREEz to create the animated GIF.]
On that note, there is something else that I would like to ask. Are there going to be any cataclysmic variable star systems such as a white dwarf surrounded by an accretion disk from a nearby companion star? Will there be neutron stars and binaries modeled into your simulation? And finally,
![](/images/smilies/happy.gif)
, will there be any black hole binaries in your simulation?
I saw this video on YouTube illustrating the latter, and the model looks very similar to the black hole that you have created:
http://www.youtube.com/watch?v=nsbGDQMZeI0
That's all I have, and again outstanding job on the oblated stars,
![](/images/smilies/grin.gif)
.