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February 24, 2005 -
Stellar Structure Software On-Line
The ZIP files for downloading ready-to-go executable modules, instructions, and source code in C with C++ comments are now available on-line. Source code for Thermonuclear Fusion in Stars is also available on-on-line as text file source code in Borland Turbo C++ for Windows 3.1, as referenced below. This on-line software can all be easily compiled with Borland Turbo C/C++ for Windows 3.1 to modify the code and produce new experimental executable modules. A Borland Turbo C/C++ 4.5 edition of this code may be implemented eventually, but is not yet available. Otherwise, the book Thermonuclear Fusion in Stars by James A. Green from Greenwood Research may be ordered to obtain the executable modules together with the source code on 3 diskettes.
If you would like to try modifying the code to devise your own models, Borland Turbo C++ for Windows 3.1 is still available for $49.00 from EMS Professional Software. You might also try some of the numerous free C++ compilers available.

Stellar Structure Software by James A. Green. Source Code Included | March 4, 2004.
CHANDRA Collapsed Objects by the method of Chandrasekar & Fowler. | chandra.txt | chandra code.
STARCAL Fusion and Stellar Evolution Software Series | ReadMe Notes
__ FUSION - Free fusion process investigator code with stellar evolution & star age calc. | fusion.txt
__ STAR8 - 2nd-order solar evolution abundance investigator. | star8.txt | star8 code free online. Sun only.
__ DEPTHSTA - Free stellar distance ranging using astrophysical stellar modeling. | depthsta.txt | depthsta.exe.
__ STAREXP - Free code, Contains Supernova Report Generator for stars over 6.3 solar masses. | starexp.txt || SN links
__ STAREXP5 - Free Zero Age Main Sequence modeler, compact.

CALCULATING PI : Four methods for calculating pi = 3.14159.... Godhead Visions

Structured Programming Philosophy : Easy-to-understand, modify, and improve. Windows-compatible.

Press to download chandra.zipCHANDRA, press here for free download. 102 Kb | Back to top Back to top
Stellar structure software for Windows, with executable module chandra.exe, source code chandra.cpp in C (Borland Turbo C++ for Windows 3.1 [See also Borland 2.1 and Free C/C++ Compilers]), and chanread.txt readme file. I could compile CHANDRA in Turbo C++ 4.5 when I tried it, although it may require modification in the 4.5 environment because its long output file is saved in the output buffer of its enclosing window when using 4.5. You will require WinZip to unzip Download WinZip 8.0 or search CNET. CHANDRA is stellar structure software for collapsed-objects by the method of Chandrasekhar and Fowler, including white dwarfs, neutron stars, and objects with more exotic equations of state. (See CHANDRA C/C++ source code chandra.cpp at, together with links to the executable module chandra.exe, sample output, and instructions.) It includes rotations and chemistry selection, preparing an overall report file chandra.txt (Press here for a look at a sample CHANDRA summary printout.) and a smaller report presented to the screen of your terminal. If specified, CHANDRA also generates a detailed center-to-surface structure file for variables like temperature, pressure, density, and so forth. (Press here for to view a sample center-to-surface CHANDRA output stellara.txt file). This download module includes the source code file chandra.cpp, which the user may modify and recompile to handle new equations of state, modified gravitation model, as desired. The complete set includes the book CHANDRA: CHANDRASEKAR SETS OF WHITE DWARFS AND SUPERNOVA CORES by James A. Green, available for $52.86 from Greenwood Research Books & Software, or from many other bookstores and dealers. The book CHANDRA includes this free downloadable software on diskette, plus a tutorial on the theoretical astrophysics treated by the software, letters from S. Chandrasekhar himself to the author written while the program was being composed, and a free copy of the old 5th edition of GRAVITATION & THE ELECTROFORM MODEL in an appendix.
Dealers & bookstores | Order Direct

Press to download STARCAL - press for free download with starexp.exe. | Back to top Back to top
Updated August, 2003. Several versions of STARCAL are now available for use with the new 2nd edition of Thermonuclear Fusion in Stars by James A. Green, list price 50 dollars. These new programs support abundance structure stored in disk file and a number of data files in a \Z6 subdirectory. This allows the new versions of STARCAL to exhaustively describe the chemistry of the modeled star, with on-board interactive modification of abundance details or default to the Aller 1961 standard based on the spectra of ejecta from planetary nebulae (X=0.60, Y=0.38, Z=0.02) nearly agreeing with my own calculation (X=0.63, Y=0.35, Z=0.02). The Aller 1961 result was used by Dr. Donald D. Clayton in his Principles of Stellar Evolution and Nucleosynthesis, replacing the relatively helium-poor abundances (23%) used earlier (X=0.75, Y=0.23, Z=0.02) by Martin Schwarzschild in his classic Structure and Evolution of the Stars. Also, the stellar evolution of the target star is treated more carefully. In particular, the effect of the aging on the radial abundance structure may be computed using higher-order approximations based on fusion process formulae, which has some small impact on stellar age calculations based on the depletion of the hydrogen core. The program starts out with a Zero Age Main Sequence Model star with the same radius as the observed star. However, one then finds that the model star is brighter than the star we observe, according to our thermonuclear calculations, because the star has aged, burning up some of its reserves of hydrogen. The programs DEPTHSTA, FUSION, and STAR8 compute the hydrogen depletion in the stellar core necessary to cause the observed reduced luminosity of the star, then compute the age of the star from this hydrogen depletion, also producing a 2nd-order map of the internal evolved stellar abundance structure in STAR8. This differs somewhat from the uniformly-mixed ZAMS Zero-Age-Main-Sequence n=3 polytrope model star we begin with. This procedure works best with the Sun.

New Readme Notes on 2003 STARCAL software.
The stellar-ranging program DEPTHSTA is now provided along with the abundance structure investigator STAR8. The compact single-module analyzer STAREXP is included, and the fusion process investigator FUSION, which does not recalculate the abundance structure, is also included. FUSION and STAR8 both use the same abundance file and /Z6 data files. FUSION, featuring on-line source code, allows one to compare the results of applying different fusion process formulae from many different astrophysicists, while the more complex STAR8 narrows the selection of available fusion formulae down to a few of the most realistic, based on past studies, and treats the effect stellar evolution on the radial distribution of abundances of the elements. Both include sophisticated p-p fusion and carbon cycle modeling for application to stars like Sirius, and do well for both Sirius and the Sun. These programs are may be run directly from the 2 diskettes used to supply the software, with or without installation on the host computer, since all data files and the /Z6 directory will be available on the 2 diskettes.

FUSION and STAR8 now include death star calculations for white dwarf formation and envelope ejection when hydrogen-burning cores collapse. The overall STARCAL package now includes these deluxe multi-module versions with their component modules, as well as a readme2.txt file with source code as shown below and features superior treatment of fusion process changes due to variation of the abundances of the elements that modify electrostatic screening for fusion. Press here to view an older multi-modular STAR4 printout for the Sun.. This 2nd edition of the STARCAL software packages allows the user to enter the name of the star, the distance or parallax of the star, the spectral type, and the visual magnitude along with a chemistry specification. The chemistry spec may be simply standard galactic halo or galactic composition, or the user may specify the chemistry in detail. The program applies bolometric corrections for atmospheric absorption to the visual magnitude, then computes a large array of model variables for the star, including the radius, luminosity, absolute magnitude, surface temperature, central and average densities, and other measures. It uses the chemistry specification to compute the nuclear luminosity of the star from the inside out, using stellar structure theory and formulae for nuclear cross-sections. STAR8, FUSION, and DEPTHSTA calculate a few features of the appearance of a Type II supernova explosion that might result, but have room for more stellar evolution details, comparative study of fusion formulae, or stellar depth ranging. For supporting theoretical astrophysics, see Thermonuclear Fusion in Stars by James A. Green. STAREXP provides a supernova report generator for stars over the 6.3 solar mass threshold for Type II supernovae. The nuclear luminosity calculations work best with Main Sequence stars like the Sun that run primarily on p-p fusion. Red giant calculations done with STAREXP5 are good for most surface variables, but not optimum with regard to nuclear luminosity. Instead, the program diagnoses the structural characteristics of the red giant deviating from normal main sequence structure. The program is useful for preparing or correcting astronomical charts incorporating astrophysical information. Some authors, for example, do not include bolometric corrections for atmospheric absorption of stellar radiation before computing the absolute magnitude, radius, and mass of a star. In addition STARCAL software (STAREXP) makes charting of Type II supernovae progenitors possible (M > 6.23 M_sun), along with other novel applications. However, the almost equally numerous Type I supernovae are not treatable with this software, as this requires precise knowledge concerning close binary pairs. I note that STARCAL computes a thermonuclear luminosity of 1.846 (Chiu p-p fusion) or 2.167 (Clayton p-p fusion) times the observed solar luminosity for the Sun when figuring solar luminosity from stellar structure theory using n=3, gamma=4/3 polytropic structural modeling, the old standard model of Eddington, Ritter, Emden, and Homer Lane. The discrepancies are due to the exhaustion of hydrogen in the core of the Sun, which would bring the abundance of hydrogen down to about 0.4395 (0.406, Clayton) in the core from about 0.597. This yields star ages of 4.52 billion years for the Sun in the Chiu case, and 5.49 billion years if the Clayton p-p fusion chain model is used. Thus FUSION, STAR8, and DEPTHSTA really do stellar evolution now from the nuclear process model. The age of the Earth is 4.5 to 4.7 billion years from experiments involving the decay of isotopes of uranium and thorium into isotopes of lead. The normalizing factors (that make the Sun come out just right and that yield the solar ages) have been omitted in some sections of the printed report prepared by the program to permit viewing details of the electrostatic screening problem and core abundance renormalization problem. Neutrino luminosity and solar wind luminosity losses are thought to amount to no more than 2% and 2 millionths of the total luminosity, respectively, so they influence the normalizing factors just a little. I note that if instead one specifies n=1.5 gamma=4/3 for the polytropic index, corresponding to a monatomic gas without radiation pressure, the nuclear luminosity is on the order of 100 times too small to match to solar luminosity, showing that the stellar luminosity is sensitive to our assumptions concerning the details of stellar structure. The n=3, gamma=4/3 approach is rigorous for a well-mixed Zero Age Main Sequence star in hydrostatic equilibrium with the gas pressure plus the radiation pressure, and gives the best results for the luminosity L_nuclear(r) when we integrate p-p fusion energy functions over the model volume. The program also computes the luminosity partition L(r)= L_convective(r) + L_radiative(r) + L_conductive(r) by applying the equation of radiative equilibrium to the radiative part of the energy transmission partition, using the result that dT/dr is determined by hydrostatic equilibrium. The radiative equilibrium part requires opacity calculations, the assumptions for which are rather well-determined, but presently compile-time options. If the star has aged, depleting it's internal store of hydrogen, the n=3, gamma=4/3 polytropic stellar models assuming a uniform internal abundance of the elements yield stars that are too bright, but one can identify the hydrogen-burning region of the star and decrease the abundance of hydrogen there until the computed luminosity matches the observed luminosity, and then compute the age of the star. This works best for the Sun, because its dimensions are precisely known. The package FUSION estimates stellar ages this way. Refinements including the detailed radial distribution of the elements after stellar evolution are treated in STAR8. The user may view on-line source code in C at starexp5.cpp for the single-module STAREXP5.

For the more advanced multi-modular 2nd edition FUSION package see the source code modules

starz7.cpp, starz7ag.cpp, starz7au.cpp, starz7bo.cpp, starz7fu.cpp, starz7op.cpp, and starz7sc.cpp. The project file is at fusion.prj, and may be used to recompile after a change using the Borland Turbo C++ for Windows 3.1 compiler.
Also see abundan.txt, and the 15 \z6 source files
abundan.txt, abundan2.txt, z6astcal.txt, z6bocal.txt, z6brite.txt, z6dwarf.txt, z6giants.txt, z6help.txt, z6listm.txt, z6near.txt, z6spect.txt, z6superg.txt, z6tsurf.txt, z6mnseq.txt, z6sketch.txt

Free Download fusion.zipFUSION - press for free download of 121 Kb | Back to top Back to top
The above download contains the executable fusion.exe. To run it, download and extract fusion.exe with WinZip.
Place fusion.exe in a directory with abundan.txt, which you may copy using the above links. Also, create the sub-directory \z6 and place the 15 \z6 source files listed above in this \z6 sub-directory. You may then run fusion.exe, following the instructions on its main menu to select functions and set up a model star. The output is to the console and to the report file fusion.txt, which is written into the same directory as fusion.exe inhabits. The output is re-written each time the program is run, so rename the output file at the end of each run to save old results. Also, abundan.txt, which appears in the same directory as fusion.exe and the primary output fusion.txt, will save the last abundance hypothesis that you were testing.

Free Download STAR8 components.STAR8 2nd-order solar evolution abundance investigator
The starz8-series 2nd-order solar evolution abundance investigator STAR8 is also now free online. For the Sun, it produces this solar star8.txt output file. At this time it fails for most other stars, and may be updated soon to extend its domain of application.
For the most recent incarnation of the 2nd edition STARCAL software packages, please have your library buy a copy of the associated textbook. Every package can be executed from one of 2 diskettes, or the software can be installed on the host system's hard disk drive. More advanced code for stellar evolution, galactic evolution, and other astrophysical applications has been developed and is included on the 2 textbook diskettes. For the latest announcements on related product developments, see Greenwood Research Announcements.

Free Download depthsta.zipDEPTHSTA|June 18, 2002|8:45AM|
Stellar Depth Ranging - Free download.279Kb

Use WinZip to extract the executable module depthsta.exe from When the program is executed, it will call from input from the console. The program leaves its output in depthsta.txt and on the console.

Free Download starexp.zipSTAREXP Supernova Details for stars over 6.3 solar masses.
The download should be processed with WinZip to extract starexp.exe. This older program starexp.cpp contains a supernova report generator giving details of Type II supernova events for progenitor stars of over 6.3 solar masses. Output is to starexp.txt. It is less useful for a fusion process and stellar evolution analysis that FUSION and STAR8.

The complete set includes the STAR8 2nd-order structure investigator for stellar evolution as well as the free source code for DEPTHSTA, FUSION, CHANDRA, and other astrophysics applications together with the book
Thermonuclear Fusion in Stars by James A. Green, 2nd edition, from Greenwood Research, also available through Dealers and Bookstores.

CALCULATING PI - press for free download. 71 Kb | Back to top Back to top
This software includes archpi.exe, chinpi.exe, leibnitz.exe, and newton.exe together with the corresponding Borland Turbo C++ for Windows 3.1 source code modules for calculating pi by the method of Archimedes, the Chinese method, by the method of Leibnitz, or by the method of Newton. The most rapidly converging method is due to Archimedes, involving inscribing a circle between interior and exterior polygons. The software contains explanations and it is entertaining to observe the relative rates of convergence.
The corresponding textbook Calculus for the Systems Architect: An Essay on the Eternal by James A. Green from Greenwood Research contains the development of the calculus in addition to entertaining sections on the history of the calculation of pi and the application of calculus to problems in engineering and science.
Dealers & Bookstores | Order Direct

This code is written to be easy-to-understand, easy-to-modify, easy-to-maintain and extend. It leans toward the structured design philosophy popularized by Glenford Myers of the IBM Research Institute. It is user- modifiable code written to be simply passed on to another generation of experimenters. Object-Oriented design methods emphasizing barriers difficult for neophytes to quickly scale have been avoided. If the user fouls up, the old original code can always be downloaded from online, re-modified, and recompiled with a Borland Turbo C++ for Windows 3.1 - compatible compiler. This has conceptual advantages for scientists under conditions in which security is not a paramount concern. A structured table of contents is provided, and I have loosely adhered to the idea of writing short modules that are functionally cohesive, with well-defined inputs and outputs.

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M16 Nebula detail.  Hubble Space Telescope astrophoto, NASA. For other cosmic & terrestrial nebular imaging examples, see Einstein & WeatherVisions.Also download the free XAOS Fractal Zoomer with Fractal Knockers!
From a column 1 light-year high, high spirits seem to shine through
from the Star Queen Nebula in M16 in Serpens
along the Milky Way near the galactic hub. NASA HST astrophoto.
David Malin Astrophotos | Constellations | Nebulae | Green's Visionary Universe

Music: Voices in the Sky & Om from In Search of the Lost Chord by The Moody Blues
and Quantum States of a Classical Gas by Mason Williams.

Please send remarks & corrections to
The Human Spirit in the Mists of Space. Press for Weather Visions.
Green On High in the Overmind: Profile in Supernova Remant N 63A. || Home | Orionsky
This scene is located in the Large Magellanic Cloud between constellations Dorado and Mensa,
the "cock and balls" of the celestial sphere beneath Orion. Also see the YouTube Video Cosmic Pepper 4.