Downloads of C2A Software, Catalogues and Tools

DistributionsOrbital ElementsCataloguesCompilersMiscellaneous

If it is the first time you download C2A, you just need to get the most recent full version of the software (use the first link in the Distributions section below). All what you need in a first time is included in the distribution package.

In addition to the distribution packages of C2A, this page provides you with a certain number of downloads:

Distributions

The most two recent versions of C2A are available for download in this section. It is advised to install the latest version, the other one being here in case of a regression is found in the most recent version.


Most Recent Version August 12, 2014
Version 2.0.53 - full distribution39.4 MBFull distribution in English (1)
Version 2.0.53 - update9.5 MBUpdate to version 2.0.53 (2)

New features in version 2.0.53


Version before the most Recent Version March 23, 2014
Version 2.0.52 - full distribution39.1 MBFull distribution in English (1)
Version 2.0.52 - update9.2 MBUpdate to version 2.0.52 (2)

New features in version 2.0.52


(1) If a version older than 2.0.35 is already installed on your system, uninstall it first using the Windows configuration pannel. Once this is done, you can then install the new version. Note that your settings will be preseved. If a version newer than 2.0.35 is already installed on your system, you do not have to uninstall C2A first. The newer version will overwrite the older one.

(2) The update package must only be used if a version 2.0.40 of C2A or newer is already installed on your computer. If it is not the case, please use the full distrbution package and not the update package.

To install C2A on your system, simply "unzip" the content of the ZIP file into a temporary folder, then launch the executable setup.exe. Finally, follow the different steps of the installation procedure as proposed by the installation software.

Orbital Elements

This section allows you to download orbital elements files so that they can be imported in the C2A Asteroids and Comets tool. These orbital elements are updated on a regular basis. It is recommanded however to use the automatic importing function which is available in the Asteroids and Comets tool rather than downloading the orbital elements manually.

All the orbital elements provided in this page are in the C2A format (which is a very simple text format). To download these files on your computer, make a mouse right click on the links, then use the Save as... command.

Last Update: Novemebr 20, 2014

Observable Comets

The file com_obs.c2a contains a list of observable comets (obtained from the Minor Planet Center site). The URL that can be used directly within C2A is:
http://www.astrosurf.com/c2a/orbel/com_obs.c2a

500 First Asteroids

The file ast_500.c2a contains orbital elements for the 500 first asteroids (obtained from the site of the Bowell Catalogue). The URL that can be used directly within C2A is:
http://www.astrosurf.com/c2a/orbel/ast_500.c2a

1000 First Asteroids

The file ast_1000.c2a contains orbital elements for the 1000 first asteroids (obtained from the site of the Bowell Catalogue). The URL that can be used directly within C2A is:
http://www.astrosurf.com/c2a/orbel/ast_1000.c2a

2000 First Asteroids

The file ast_2000.c2a contains orbital elements for the 2000 first asteroids (obtained from the site of the Bowell Catalogue). The URL that can be used directly within C2A is:
http://www.astrosurf.com/c2a/orbel/ast_2000.c2a

Bright Asteroids

The file ast_brgt.c2a contains the orbital elements of the bright asteroids at opposition in the current year (obtained from the Minor Planet Center site). The URL that can be used directly within C2A is:
http://www.astrosurf.com/c2a/orbel/ast_brgt.c2a

Critical Asteroids

The file ast_crit.c2a contains orbital elements for the critical asteroids (obtained from the Minor Planet Center site). The URL that can be used directly within C2A is:
http://www.astrosurf.com/c2a/orbel/ast_crit.c2a

Specific Asteroids

The file ast_nea.c2a contains orbital elements for distant asteroids (obtained from the Minor Planet Center site). The URL that can be used directly within C2A is:
http://www.astrosurf.com/c2a/orbel/ast_nea.c2a

Astéroïdes distants

The file ast_dist.c2a contient les éléments orbitaux des astéroïdes distants (obtenus depuis le site du Minor Planet Center). The URL that can be used directly within C2A is:
http://www.astrosurf.com/c2a/orbel/ast_dist.c2a

In order to load the orbital elements provided in this page, simply use the Import dialog box of the C2A Asteroids and Comets tool (which can be displayed using the button Import... of the Asteroids and Comets tool dialog box). Once this dialog box is displayed, simply specify the name of the file to be imported (assuming it has been saved locally on your disk) or use directly the URLs proved above.

Pay special care to correctly position the Asteroid and Comet buttons before starting the importation process. Furthermore, you must check that the import format is in accordance with the format of the file to be imported (in our case it is the C2A format).

Catalogues

Large C2A Catalogues
Tycho-2 Catalogue152 MB

This ZIP file contains the Tycho-2 catalogue in the C2A format and must be decompressed to be used by the program. This version includes the two supplement catalogues. It also corrects a problem with the stars from the supplement catalogue (found on the 1st of May 2007).

Guide Star Catalogue131 MB

This ZIP archive contains the Guide Star 1.1 catalogue in its compiled format for C2A. The files in the ZIP file must be uncompressed into a folder (named GSC for instance) preserving the sub-directory structure.

BT-Atlas Images620 MB

All the BT-Atlas images are available in this ZIP archive in the PIC format (the format from the well known Iris image processing software) with all their dynamic. The files in the ZIP file must be uncompressed into a folder (named BT-Atlas for instance) preserving the sub-directory structure. The author wants to thank Christian Buil for having given free access to this great image catalogue.

To download these files on your computer, make a mouse right click on the links, then use the Save as... command. Once these catalogues are downloaded on your disk drive, you must declare the access paths in the tab Paths of the Options dialog box (F7 keyboard shortcut within C2A).


Text Catalogues
Reduced UGC Catalogue15 KB

Text catalogue example in the C2A format.

To download this file on your computer, make a mouse right click on the link, then use the Save as... command.

The syntax of text catalogues is described in the C2A Help system. Text catalogues usually have the extension ".c2a". Text catalogues can be loaded in C2A using the command User Catalogues... from the File menu.


Compiled Catalogues
4th Uhuru Catalogue4U.ccc30 KB
Abell Clusters of GalaxiesAbell.ccc198 KB
Arp Atlas of Peculiar GalaxiesArp.ccc17 KB
Bonner Durchmusterung CatalogueBD.ccc16 MB - ZIP file
Flat Galaxy CatalogueFGC.ccc386 KB
Fifth Fundamental CatalogueFK5.ccc158 KB
General Catalogue of Variable StarsGCVS.ccc3.7 MB
Hickson Galaxy Cluster CatalogueHickson.ccc7 KB
Hipparcos Input CatalogueHippar.ccc9.9 MB
High Velocity StarsHVS.ccc52 KB
Lynds' Catalogue of Bright NebulaeLBN.ccc61 KB
Lynds' Catalogue of Dark NebulaeLDN.ccc134 KB
UBVRI photometry of faint field starsLoneos.ccc3.7 MB
MBrphological Catalogue of GalaxiesMCG.ccc2.5 MB
Merged Catalogue of GalaxiesMERCG.ccc2.7 MB
New Suspected VariablesNSV.ccc3 MB
Open Cluster DataOPENCL.ccc55 KB
Galactic Planetary NebulaePLN.ccc83 KB
Northern PPM CataloguePPMNORTH.ccc25 MB - ZIP file
Southern PPM CataloguePPMSOUTH.ccc20 MB - ZIP file
Ruprecht Star ClustersRuprecht.ccc9 KB
Sharpless HII CatalogueHII.ccc15 KB
Galactic Supernova RemnantsSNR.ccc11 KB
Uppsala General CatalogueUGC.ccc1.4 MB
Washington Visual Double StarsWDS.ccc4.3 MB
Zwicky Clusters of GalaxiesZwicky.ccc611 KB

To download these files on your computer, make a mouse right click on the links, then use the Save as... command.

The C2A catalogue compiler can be downloaded from this same page (section Compilers). It is a simple executable that must be run from the Windows Command Line. All the necessary steps to create a compiled catalogue are described in the C2A Help System. Compiled catalogues must have the extension ".ccc". Compiled catalogues can be loaded in C2A using the command User Catalogues... from the File menu.

Compilers

User Catalogue Compiler

Version 1.1.0
(Windows 7 64 bits compatible)

Text user catalogues are useful when catalogues are not too big. However, for large catalogues, loading time within C2A et screen refresh become prohibitives.

C2A offers the possibility to compile an object catalogue. This means that a binary file can be produced from an ASCII file whose syntax is described by the user. This binary file can then be loaded and displayed much faster within C2A. Furthermore, users have the ability to define their own fields whose value is displayed when objects are identified within the maps.

For a text database to be compiled, the user has to provide a certain number of information in a text file called a "model file". This information will allow the database compiler to figure out which data is to be extracted from the ASCII file and used to produce the compiled file.

The database compiler for C2A is called DC and must be launched from the Windows Command Line. In order to install the compiler and use it, first download the file DC.zip using the link on the left, uncompress it, and copy the executable file DC.EXE in a directory of your choice. Then open a Windows command line (go into the Start menu, choose Execute..., then type cmd followed by OK). Go then into the directory where the DC compiler has been installed. Here, the compiler can be used using the directions provided in this short Compiler User Guide (in English).

Note: The old DOS version 1.0.18 of the User Catalogue Compiler (which does not work on Windows 7 64 bits) is also available here.

Compiler for the UCAC1 Catalogue

Version 1.1.0
(Windows 7 64 bits compatible)

The UCAC1 catalogue is published by the US Naval Observatory under the form of a CD-ROM that contains a file called u1.tar.gz. In order to be efficiently used by C2A, this catalogue must be compiled first. To compile the UCAC1 catalogue, simply go through the following process:

  • Download first the file UCAC1.zip from the link on the left, uncompress it and copy the file UCAC1.EXE in a directory on a disk with at least 6 gigabytes of free space.
  • Insert the UCAC1 CD-ROM in your CD-ROM drive.
  • Copy the compressed file u1.tar.gz in a directory of your hard disk drive.
  • Uncompress the file u1.tar using for instance the Winzip utility.
  • Extract all the files contained in the TAR file u1.tar. The Winzip utility is also able to perform this extraction. At this step, you should have 169 files from z001 to z169 that take 1.73 gigabytes on your disk (do not forget to delete these files after the compilation process!). Note that the extraction process of the TAR file can take some time and that you need plenty of free space on the disk used by Winzip to store temporary file.
  • Open a DOS Command window (for instance by going into the Start menu, then Run... and typing CMD - this is valid for Windows XP) then go into the directory where you have copied the file UCAC1.EXE (where the compiled catalogue will be created).
  • Run the command UCAC1 "Access Path to UCAC1 files" "Compiled Catalogue Name" where "Access Path to UCAC1 files" is the access path to the directory where are located the files z001 to z169 and "Compiled Catalogue Name" is the name of the file that will contain the compiled catalogue. This command can be for instance:
    UCAC1 D:\TMP D:\UCAC1.DAT.
  • During the compilation process, 48 temporary files are created then automatically deleted after the compilation is complete. If the compilation process is stopped, all these files must be manually deleted. 27,425,433 objects must be reported by the tool.

The compilation process takes around 30 minutes on Core i5 computer (or 2 hours and 3 minutes on a Pentium III computer at 1 GHz...). The output file (for instance UCAC1.DAT) has a size of roughly 889 megabytes. Store it in a directory of your hard disk drive then specify the access path within C2A by going into the tab Paths of the Options dialog box (accessible from the menu Tools/Options...). This access path could be for instance "D:\UCAC1\UCAC1.DAT" assuming that a directory "UCAC1" has been created directly on the C: drive root. The compiled file must be exactly 932,468,278 bytes

C2A is now ready to read the UCAC1 catalogue!

Note: The old DOS version 1.0.0 of the UCAC1 compiler (which does not work on Windows 7 64 bits) is also available here.

Compiler for the UCAC2 Catalogue

Version 1.3.0
(Windows 7 64 bits compatible)

The UCAC2 catalogue is published by the US Naval Observatory under the form of 3 CD-ROMs that contain 288 files named from Z001 to Z288 as well as 36 files for the Bright Star Supplement names s01 to s36. In order to be efficiently used by C2A, this catalogue must be compiled first. To compile the UCAC2 catalogue, simply go through the following process:

  • Download first the file UCAC2.zip from the link on the left, uncompress it and copy the file UCAC2.EXE in a directory on a disk with at least 10 gigabytes of free space.
  • Copy the files Z001 to Z288 and s01 to s36 in a directory of your hard disk drive (if you do not have the Bright Star Supplement files s01 to s36 on the UCAC2 CD-ROMs, you can download them from the Miscellaneous section in this page).
  • Open a DOS Command window (for instance by going into the Start menu, then Run... and typing CMD - this is valid for Windows XP) then go into the directory where you have copied the file UCAC2.EXE (where the compiled catalogue will be created).
  • Run the command UCAC2 "Access Path to UCAC2 files" where "Access Path to UCAC2 files" is the access path to the directory where are located the files z001 to z288 and s1 to s36. This command can be for instance:
    UCAC2 D:\TMP
  • During the compilation process, 48 temporary files are created then automatically deleted after the compilation is complete. If the compilation process is stopped, all these files must be manually deleted. 48,330,571 objects must be reported by the tool.

The 24 output files (UCAC2_00.DAT to UCAC2_23.DAT) have a size of roughly 2.17 gigabytes. Store them in a directory of your hard disk drive then specify the access path within C2A by going into the tab Paths of the Options dialog box (accessible from the menu Tools/Options...). This access path could be for instance "D:\UCAC2" assuming that a directory "UCAC2" has been created directly on the C: drive root.

The compilation process takes around 1 hour and 30 minutes on Core i5 computer. Once the compilation process is complete, the source files (Z001 to Z288 and s01 to s36) can be deleted from the hard disk.

Note: The old DOS version 1.2.0 of the UCAC2 compiler (which does not work on Windows 7 64 bits) is also available here.

Miscellaneous

Polynomial File to Compute Planetary Positions between 1900 and 2100

Polynomial File wap.b98
November 6, 2006

This file must be uncompressed and must overwrite the file wap.b98 in the C2A installation directory (by default C:\Program Files\C2A).
Download size is 11.5 MB


Add-in to Use C2A with Occult Watcher

Occult Watcher Add-in
Version 1.6
November 21, 2011

Occult Watcher is a software designed to easily manage predictions of star occultation by asteroids. An Add-in is available to directly launch C2A from Occult Watcher and display a map of the occultation event (setting automatically the time, location and catalogue for the considered event). The Hipparcos, UCAC2, UCAC3 and NOMAD catalogues are often used in occultation predictions, so it is necessary to have them installed on your computer before using this Add-in.

Take care that in order to use this C2A Add-in for Occult Watcher, you need at least version 2.0.43 of C2A and the most recent version of Occult Watcher.

To install the Add-in, simply extract the file OccultWatcher.C2a.dll (available in the ZIP file) and copy it into the Occult Watcher installation folder. A C2A entry will then be added in the Occult Watcher Add-in menu. To launch C2A and get the map of an event, select this event in the Occult Watcher list and go into the Add-in menu to create the C2A Occultation Map.

New features in version 1.6 are the following:

  • A new option has been added in order to request C2A to automatically load the orbital elements of the asteroid involved in the occultation event. These orbital elements are obtained from a local Astorb.dat file that must be available on the local disk and declared in C2A using the Solar System advanced options in the Options dialogue box.


Bright Star Supplement for the UCAC2 Catalogue

Bright Star Supplement
December 3, 2006

The catalogue UCAC2 uses 36 files (s01 to s36) containing information on bright stars which must be integrated into the compiled UCAC2 catalogue for C2A. These files are not provided on all UCAC2 distributions. Therefore, they are provided here for download.
Download size is 13.3 MB


C2A for DOS

C2A DOS Version 4.1.4
September 2002

C2A is available in a DOS version which is compatible with all the Windows Operating Systems as well as in a DOSBox emulation which also runs on Mac OS. The advantage is that it can be used on hardware platforms that maybe not be powerful enough to run recent versions of Windows. This tool is therefore perfect to run a simple Planetarium program on an old machine close to the telescope.

By default, C2A for DOS is able to read three star databases (around 2100, 9000 and 260.000 objects) as well as three deep sky objects databases (around 110, 5000 and 8000 objects). All these catalogues are provided with the software. C2A for DOS is able to read the BT-Atlas catalogue (6600 objects) with its 4649 associated images. It is also possible to access the Guide Star catalogue (10 millions objects) as well as the USNO catalogues in different versions (USNO-SA1.0, USNO-A2.0). These large catalogues are not provided with the C2A for DOS distribution.

To install C2A for DOS, download first the file C2AD_414.zip with the link on the left, uncompress it in a temporary directory and run the executable INSTDOS.EXE. Then, simply follow the steps as displayed on the screen. At the end of the installation process, you can delete the files in the temporary directory.

All the documentation about C2A for DOS is available in a file called C2A.PDF provided in the ZIP archive. Take care that this documentation is in French only! Sorry about that, but it would be a tremendous work to translate it...

C2A DOS Version 4.1.5
January 2010

This is a DOS version of C2A which supports the polynomial file SLP96 from the IMCCE in order to compute planetary positions over the period 1987 - 2020. Version 4.1.4 only supports the period 1987 - 2009.

In order to install this version, install first version 4.1.4 above (if it is not already installed on your computer) then overwrite the files C2A.EXE, C2A.MSG and C2A.B98 with those from the ZIP archive file.

Last Update : August 22, 2014
Author : Philippe Deverchère