Linux Astronomy HOWTO

Elwood Downey

John Huggins

<howto@astronomy.net>
$Revision: 1.48 $


Copyright © 2000-2004 Elwood Downey and John Huggins

$Date: 2004/02/07 17:58:56 $


This document shares tips and resources to utilize Linux solutions in the
pursuit of Astronomy.

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Table of Contents
1. Introduction
    1.1. Knowledge Required
    1.2. Scope
    1.3. Disclaimer
    1.4. Version
    1.5. Copyright
    1.6. Contributions
    1.7. Translations
    1.8. About the authors
   
   
2. Software
    2.1. Collections
    2.2. Planetarium Programs
    2.3. Portable and Handheld Appications
    2.4. Simulators
    2.5. Image Processing
    2.6. Sun and Moon
    2.7. Libraries
    2.8. Games
    2.9. Other
   
   
3. Online Tools
    3.1. Traditional Form Based Programs
    3.2. Java Applets
   
   
4. Astronomical Images over the web
    4.1. List
   
   
5. Organizations
6. Hardware Control
    6.1. Telescope Control
    6.2. CCD Camera Control
   
   
7. Installation Help
8. Projects using Linux
9. Revision History

1. Introduction

1.1. Knowledge Required

With all the help from major Linux distributions such as SuSE, Redhat and
many others, Linux based systems are becoming easier to use. However, there
is still some need of understanding of basic UNIX skills to make the most of
Linux. Thus, this HOWTO will assume that the reader has at least a basic
knowledge of using a UNIX system including the ability to compile and install
programs.

A few resources we have found useful over the years include:

  * "A Practical Guide to the UNIX System", Mark G. Sobel
   
  * "Advanced Programming in the UNIX Environment", the late W. Richard
    Stevens
   
  * "Running LINUX", Matt Welsh et al.
   
  * "LINUX Device Drivers", Alessandro Rubini
   

Similarly, this is not a tutorial or reference for astronomy principles or
astronomical instrumentation. Astronomy is perhaps the grandest of all
sciences, employing widely disparate disciplines in a bold attempt to
understand nothing less than the universe itself. Your interests will lead in
many directions. A few references we have used include:

  * "Explanatory Supplement to the Astronomical Almanac", P. Kenneth
    Seidelmann
   
  * "Astronomy with your Personal Computer", Peter Duffett-Smith
   
  * "Astronomy on the Personal Computer", Oliver Montenbruck et al
   
  * "Textbook on Spherical Astronomy", W. M. Smart
   
  * "The Astronomy and Astrophysics Encyclopedia", Stephen P. Maran, ed.
   

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1.2. Scope

The authors define the scope of this HOWTO as primarily an index to Linux
tools applicable in some fashion to the pursuit of Astronomy. It is NOT our
intention to list WWW astronomy references in general. Our own interests tend
more towards the technology than the pure science and so we welcome
contributions from others who have found Linux tools which contribute in
other ways to Astronomy. Please contact us at the address above.
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1.3. Disclaimer

No liability for the contents of this documents can be accepted. Use the
concepts, examples and other content at your own risk. As this is a new
edition of this document, there may be errors and inaccuracies, that may of
course be damaging to your system. Proceed with caution, and although this is
highly unlikely, the author(s) do not take any responsibility for that.

All copyrights are held by their by their respective owners, unless
specifically noted otherwise. Use of a term in this document should not be
regarded as affecting the validity of any trademark or service mark.

Naming of particular products or brands should not be seen as endorsements.

You are strongly recommended to take a backup of your system before major
installation and backups at regular intervals.
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1.4. Version

$Revision: 1.48 $

$Date: 2004/02/07 17:58:56 $

The latest version of this document is always available on the [http://
astronomy.net/] Astronomy Net at [http://howto.astronomy.net/howto/]
Astronomy HOWTO.

We eagerly accept suggestions from you. Send them to [mailto:
howto@astronomy.net] Astronomy HOWTO Editors.
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1.5. Copyright

Copyright 2000-2003 by Elwood Downey and John Huggins. This document may be
distributed only subject to the terms and conditions set forth in the LDP
License except that this document must not be distributed in modified form
without the author's consent.

A verbatim copy may be reproduced or distributed in any medium physical or
electronic without permission of the author. Translations are similarly
permitted without express permission if it includes a notice on who
translated it. Commercial redistribution is allowed and encouraged; however
please notify authors of any such distributions.

Excerpts from the document may be used without prior consent provided that
the derivative work contains the verbatim copy or a pointer to a verbatim
copy.

Permission is granted to make and distribute verbatim copies of this document
provided the copyright notice, the list of authors and this permission notice
are preserved on all copies.

In short, we wish to promote dissemination of this information through as
many channels as possible. However, we wish to retain copyright on this HOWTO
document, and would like to be notified of any plans to redistribute this
HOWTO. For information about translations of this document, please see below.
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1.6. Contributions

As we pursue the goals of the Astronomy HOWTO, we will recogize the
contributions of folks who provide us with data here.

  * Progga - Helped us get this document into modern times by converting the
    older linuxdoc to docbook.
   

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1.7. Translations

Since Astronomy is very much an international effort, we encourage
translation of this HOWTO into any language. We only ask the following:

  * If you are a translator, please contact us at the above address so we may
    give proper credit here. This way, readers will immediately see what
    translations are available and see where to get them.
   
  * Please obtain the latest copy of the Astronomy HOWTO from its home at
    [http://howto.astronomy.net/] Astronomy Net before you begin your
    translation effort.
   

We thank the following for their translation efforts:

  * [http://w3studi.informatik.uni-stuttgart.de/~moltenml/downloads.html]
    German Translation courtesy of Michael Moltenbrey
   
  * [http://www.linux.or.jp/JF/JFdocs/Astronomy-HOWTO.html] Japanese
    Translation courtesy of Shouhei Nagaoka
   

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1.8. About the authors

Elwood Downey has over two decades experience in software engineering for
various astronomy projects. Learn more about Elwood at [http://
www.clearskyinstitute.com/resumes/ecdowney/resume.html] Clear Sky Institute.

John Huggins has over fifeteen years years experience in hardware engineering
including eight years associated with an astronomy project. Learn more at
[http://www.johnhuggins.com/resume/] John's Site.
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2. Software

Software Section
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2.1. Collections

Here are some links to collections and other indexes of Linux astronomy
software.

  * [http://www.randomfactory.com/lfa.html] The Linux for Astronomy CDROM
   
  * [http://SAL.KachinaTech.COM/Z/4/index.shtml] Scientific Applications on
    Linux (SAL), Physics and Astronomy
   
  * [http://home.xnet.com/~blatura/linapp3.html#science] Linux Applications
    and Utilities Page, Science and Math
   
  * [http://bima.astro.umd.edu/nemo/linuxastro/astromake/] AstroMake is a
    utility intended to make installations of some common astronomical
    packages (in binary form) easy.
   
  * The linuxastro mailing list also contains a list of applications and
    packages. For more information, see [http://bima.astro.umd.edu/nemo/
    linuxastro] linuxastro.
   
  * [http://sourceforge.net/softwaremap/trove_list.php?form_cat=134]
    Astronomy at sourceforge.net
   

If the above does not appeal to your needs, these links may help:

  * [http://www.google.com/search?q=Astronomy+Software+Linux] Linux Astronomy
    Software from the Google Search Engine
   
  * [http://dir.yahoo.com/Science/Astronomy/Software/] Astronomy Software
    from the Yahoo Listings
   

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2.2. Planetarium Programs

Here is discussion of programs which run on Linux for use in finding objects,
natural and man-made, in the sky.

  * [http://clearskyinstitute.com/xephem/] XEphem has been the pet project of
    one of us (Downey) for the past 15-odd years. It has grown to become one
    of the more capable interactive tools for the computation of astronomical
    ephemerides.
   
  * [http://www.astrotrf.net:8080/xsky_blurb.html] XSky is by Terry R.
    Friedrichsen, terry@venus.sunquest.com. XSky is essentially an
    interactive sky atlas.
   
  * [http://edu.kde.org/kstars/] KStars is a Desktop Planetarium for KDE.
   
  * [http://tdc-www.harvard.edu/software/skymap.html] Skymap is an
    astronomical mapping program written in Fortran and C for unix
    workstations by Doug Mink of the Smithsonian Astrophysical Observatory
    Telescope Data Center.
   
  * [http://www.astroarts.com/products/xplns/] Xplns reproduces real starry
    sky on your display of X Window System.
   
  * [http://www.lsw.uni-heidelberg.de/~rwichman/Nightfall.html] Nightfall is
    an astronomy application for fun, education, and science. It can produce
    animated views of eclipsing binary stars, calculate synthetic lightcurves
    and radial velocity curves, and eventually determine the best-fit model
    for a given set of observational data of an eclipsing binary star system.
   
  * [http://nova.sourceforge.net] NOVA free Integrated Observational
    Environment for astronomers.
   

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2.3. Portable and Handheld Appications

The advance of palm computers has taken hold. Linux has made its way to this
realm.

  * Clear Sky Institute brings us the [http://www.clearskyinstitute.com/psc/]
    Personal Sky Chart for the Sharp Zaurus PDA.
   

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2.4. Simulators

Programs that classify themselves as simulators.

  * [http://www.shatters.net/celestia/] Celestia Real-time visual simulation
    of space for Windows and Unix(Linux)
   
  * [http://openuniverse.sourceforge.net/] OpenUniverse Simulates the Solar
    System bodies in 3D in Windows and Linux
   

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2.5. Image Processing

  * Astronomical Information Processing System (AIPS) is the heavy iron used
    by professional astronomers. [http://aips2.nrao.edu/docs/aips++.html]
    AIPS++ is the place to find out more, but note that [http://
    www.aoc.nrao.edu/aips/] AIPS Classic also exists and is actively
    maintained.
   
  * Good ol' [http://www.gimp.org/] GNU Image Manipulation Program (GIMP) is
    a fine program to use for processing of digital images of all kinds and
    can prove useful for astro images as well.
   

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2.6. Sun and Moon

A surprising number of applications deal with just the Sun and Moon.

  * [http://nis-www.lanl.gov/~mgh/WindowMaker/DockApps.shtml] wmMoonClock
    shows lunar ephemeris to fairly high accuracy and is listed at this web
    site along with several other interesting programs.
   
  * [http://www.paganlink.org/downloads/astronomy/xvmoontool.html] XVMoontool
    is an XView application which displays information about the Moon in real
    time.
   
  * [http://www.flaterco.com/xtide/] XTide is a Harmonic tide clock and tide
    predictor.
   

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2.7. Libraries

This section discusses bits and pieces of software that can be used to form
the basis for specialized projects.

  * [http://rlspc5.bnsc.rl.ac.uk/star/docs/sun67.htx/sun67.html#xref_]
    SLALIB, part of the [http://star-www.rl.ac.uk] Starlink Project, is a
    complete library of subroutines for astrometric computations.
   
  * [http://ascl.net] Astrophysics Source Code Library is a collection of
    links to numerical astrophysical process models.
   
  * [http://people.ne.mediaone.net/moshier/index.html] Astronomy and
    numerical software source codes is a collection of C codes related to
    astronomy.
   
  * [http://hem.passagen.se/pausch/comp/ppcomp.html] How to compute planetary
    positions.
   
  * [http://dimensional.com/~ashe/ccd-astro.html] CCD Astronomy on Linux. A
    library of routines that help control SBIG cameras.
   

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2.8. Games

Yes, games.

  * [http://www.head-crash.com/orbit/] Orbit - Be a space fighter pilot in
    Windows or Linux.
   

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2.9. Other

Every list needs a miscellaneous section, and this is it for Software.

  * [http://iraf.noao.edu] IRAF is a gigantic but exceptionally capable
    astronomical analysis system, shepherded over the past 20-odd years by
    Doug Tody formally at NOAO. It has accumulated innumerable authoritative
    contributions from leading astronomers in all areas of astronomical data
    analysis. If you have a serious interest in astronomical data reduction
    and significant time to invest, this system will reward you mightily.
   
  * [http://www.lsw.uni-heidelberg.de/~rwichman/Nightfall.html] Nightfall
    Eclipsing Binary Star Program
   
  * [http://xplanet.sourceforge.net] Xplanet Very realistic rendering program
    for Earth and other planets and moons. Uses X Windows and OpenGL.
   
  * [http://www.princeton.edu/~kmccarty/starplot.html] StarPlot A
    3-Dimensional Star Chart Viewer for Linux. Uses C++ and Gtk+.
   

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3. Online Tools

I know we said we would not start listing Web sites, but here are a few links
to sites which offer fully operational tools running online that we feel are
especially useful or interesting, from a browser on any platform.
-----------------------------------------------------------------------------

3.1. Traditional Form Based Programs

  * [http://aa.usno.navy.mil/data/docs/RS_OneYear.html] Sun and Moon Rise and
    Set calculator
   
  * [http://aa.usno.navy.mil/data/docs/WebMICA_2.html] Web version of MICA
   
  * [http://ssd.jpl.nasa.gov/cgi-bin/eph] JPL Ephemeris Generator
   
  * [http://space.jpl.nasa.gov] Solar System Simulator
   
  * [http://www.cleardarksky.com/csk/] Clear Sky Clock will show at a glance
    when we might expect clear and dark skies for one particular observing
    site.
   
  * The [http://simbad.harvard.edu/cgi-bin/WSimbad.pl] Simbad astronomical
    database provides basic data, cross-identifications and bibliography for
    astronomical objects outside the solar system.
   

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3.2. Java Applets

  * [http://www.sweethome.de/giesen/GeoAstro/GeoAstro.html] GeoAstro Applet
    Collection by Juergen Giesen
   
  * [http://aladin.u-strasbg.fr] Aladin Interactive Sky Atlas
   
  * [http://www.astro.queensu.ca/~dursi/dm-tutorial/cluster-sim.html] Cluster
    simulator
   
  * [http://www.phys.vt.edu/~jhs/SIP] Sky Image Processor
   
  * [http://liftoff.msfc.nasa.gov/RealTime/JTrack/3d/JTrack3D.html] J-Track
    3D - Satellite Tracking
   

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4. Astronomical Images over the web

Much effort exists to allow access to Astronomical image file type such as
FITS from any web browser. Here are some pointers.
-----------------------------------------------------------------------------

4.1. List

The folks at harvard have a list of Image Servers and Image Browsers.

  * [http://tdc-www.harvard.edu/astro.image.html] Astronomical Images Over
    the Web
   

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5. Organizations

  * The yearly [http://hea-www.harvard.edu/adass] Astronomical Data Analysis
    Software and Systems, ADAAS, Conference Series provides a forum for
    scientists and computer specialists concerned with algorithms, software
    and operating systems in the acquisition, reduction and analysis of
    astronomical data. The program includes invited talks, contributed papers
    and poster sessions as well as user group meetings and special interest
    meetings ("BOFs''). All these activities aim to encourage communication
    between software specialists and users, and also to stimulate further
    development of astronomical software and systems.
   
  * The linuxastro mailing list, linuxastro@majordomo.cv.nrao.edu, is for
    people who are interested in porting astronomical software to linux. For
    more information, see [http://bima.astro.umd.edu/nemo/linuxastro]
    linuxastro.
   

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6. Hardware Control

More folks are using Linux to control equipment. Users range from amateur
astronomers in the field to professional observatories.
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6.1. Telescope Control

  * [http://ktelescope.sourceforge.net/] KTelescope is a robust Client/Server
    control library for Meade's LX200 based telescopes. Is uses the
    Instrument Neutral Distributed Interface (INDI) protocol.
   
  * [http://sourceforge.net/projects/observatory] Talon, formerly [http://
    www.clearskyinstitute.com/Company/History.html] OCAAS, is a complete
    observatory control and astronomical analysis system for Linux.
   
  * [http://clearskyinstitute.com/xephem/] XEphem has the capability to
    communicate with a telescope control daemon process.
   

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6.2. CCD Camera Control

  * [http://www.apogee-ccd.com/software.html] Apogee Instruments Inc supports
    their line of professional CCD cameras under Linux.
   
  * [http://www.fli-cam.com/] Finger Lates Instrumentation Manufacturer of
    CCD cameras and filter wheels and include drivers for Linux.
   
  * [http://www.sbig.com/sbwhtmls/linux_announcement.htm] SBIG offers some
    assistance with operating their ST7 and ST8 CCD cameras under Linux.
   
  * [http://dimensional.com/~ashe/ccd-astro.html] CCD Astronomy on Linux
    These pages describe a number of facets of using astronomical CCD cameras
    for image acquisition and processing under Linux.
   
  * [http://home.earthlink.net/~dschmenk] Gccd is a gnome-based CCD camera
    and filter wheel control program.
   

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7. Installation Help

You need to know what you're doing with Linux and installing programs, but
help is available for some programs. Here are some ways to make life easier.

  * [http://bima.astro.umd.edu/nemo/linuxastro/astromake/] AstroMake is a
    utility intended to make installations of some common astronomical
    packages (in binary form) easy.
   
  * XEphem requires several elements to exist on your machine. Life is much
    simpler with the CDROM version of the program as it contains an
    installation script which loads the appropriate precompiled binary for
    most systems and places all auxiliary files to the correct spots. See
    [http://www.clearskyinstitute.com/ecommerce/xephem/order.html] XEphem
    CDROM
   

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8. Projects using Linux

Here is a list of astronomy projects using Linux in whole or in part of their
instrumentation:

  * [http://www.chara.gsu.edu/CHARA/index.html] The CHARA Array is an optical
    interferometer project using Linux in their control system.
   
  * [http://www.eso.org/projects/caos] CAOS Club of Amateurs in Optical
    Spectroscopy.
   

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9. Revision History

In an effort to record a history of the evolution of this document, we
maintain it within a CVS repository. What follows is the steps to today's
document.

+-----------------------------------------------------------------------------------------------------------------------------------------+
|$Log: Astronomy-HOWTO.sgml,v $                                                                                                           |
|Revision 1.48  2004/02/07 17:58:56  jhuggins                                                                                             |
|Another ulink fix removing expired attribute 'name.'                                                                                     |
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|Revision 1.47  2004/02/07 17:55:24  jhuggins                                                                                             |
|Fixed a ulink issue with the Talon link.                                                                                                 |
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|Revision 1.46  2004/02/05 01:22:32  ecdowney                                                                                             |
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|Add entry for Talon now that it is GPL                                                                                                   |
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|Revision 1.45  2004/01/20 13:51:17  jhuggins                                                                                             |
|Changed URL of German translation and changed the copyright date.                                                                        |
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|Revision 1.44  2003/04/21 11:44:17  jhuggins                                                                                             |
|Adjusted the name of a contributor.                                                                                                      |
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|Revision 1.43  2003/04/21 01:58:59  jhuggins                                                                                             |
|Wholesale changes including several new links, several new sections and a                                                                |
|few corrections to previous information.                                                                                                 |
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|Revision 1.42  2003/04/20 19:26:09  jhuggins                                                                                             |
|Testing CVS keywords in docbook tags.                                                                                                    |
|Revision has no : at the end.                                                                                                            |
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|Revision 1.41  2003/04/20 15:45:12  jhuggins                                                                                             |
|Placed the CVS Log keyword within the screen parameter to avoid troubles.                                                                |
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|Revision 1.40  2003/04/20 15:42:13  jhuggins                                                                                             |
|Added a revision history to the tail end of the document to avoid it cluttering the top.                                                 |
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|revision 1.39                                                                                                                            |
|date: 2003/04/20 03:58:00;  author: jhuggins;  state: Exp;  lines: +540 -264                                                             |
|First conversion to Docbook.  No content was changed, only the tags.                                                                     |
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|revision 1.38                                                                                                                            |
|date: 2001/08/27 20:45:52;  author: astro;  state: Exp;  lines: +4 -4                                                                    |
|Added Michael Moltenbrey's german translation to the list of translators.                                                                |
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|revision 1.37                                                                                                                            |
|date: 2001/08/19 18:24:25;  author: ecdowney;  state: Exp;  lines: +8 -3                                                                 |
|Add gccd                                                                                                                                 |
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|revision 1.36                                                                                                                            |
|date: 2001/07/25 19:58:54;  author: astro;  state: Exp;  lines: +26 -7                                                                   |
|Added Translator information and fixed a few text format lines.                                                                          |
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|revision 1.35                                                                                                                            |
|date: 2001/06/18 18:48:42;  author: astro;  state: Exp;  lines: +5 -3                                                                    |
|Fixed a few more sgml bugs.                                                                                                              |
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|revision 1.34                                                                                                                            |
|date: 2001/06/18 18:43:42;  author: astro;  state: Exp;  lines: +12 -5                                                                   |
|More errors fixed.                                                                                                                       |
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|revision 1.33                                                                                                                            |
|date: 2001/06/18 18:23:11;  author: astro;  state: Exp;  lines: +6 -5                                                                    |
|Fixed a few bugs in 1.32.  John                                                                                                          |
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|revision 1.32                                                                                                                            |
|date: 2001/06/18 18:11:39;  author: astro;  state: Exp;  lines: +19 -4                                                                   |
|I added a simulation and games section with a few new links.  I also corrected a few spacing issues.  John.                              |
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|revision 1.31                                                                                                                            |
|date: 2001/06/15 13:37:58;  author: astro;  state: Exp;  lines: +13 -6                                                                   |
|Change the working of the Online Tools section, divided up the tools into form based and Java Applet based and added a few new listings. |
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|revision 1.30                                                                                                                            |
|date: 2001/06/14 20:17:26;  author: astro;  state: Exp;  lines: +4 -4                                                                    |
|Added a space between link for CAOS and its name.                                                                                        |
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|revision 1.29                                                                                                                            |
|date: 2001/06/14 20:07:08;  author: astro;  state: Exp;  lines: +5 -5                                                                    |
|Removed the word "Linux" from the Yahoo link as this is just Astronomy Software.                                                         |
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|revision 1.28                                                                                                                            |
|date: 2001/06/14 20:03:18;  author: astro;  state: Exp;  lines: +4 -4                                                                    |
|Fixed missing quote in the Yahoo Astronomy Software link.                                                                                |
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|revision 1.27                                                                                                                            |
|date: 2001/06/14 19:59:33;  author: astro;  state: Exp;  lines: +5 -4                                                                    |
|Added link to the Yahoo Astronomy Software directory.                                                                                    |
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|revision 1.26                                                                                                                            |
|date: 2001/06/14 19:34:32;  author: ecdowney;  state: Exp;  lines: +16 -9                                                                |
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|revision 1.25                                                                                                                            |
|date: 2001/06/14 18:48:10;  author: astro;  state: Exp;  lines: +47 -49                                                                  |
|Changed htmlurl to url so the links appear in the txt file along with the html files. htmlurl suppresses the links in the text.          |
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|revision 1.24                                                                                                                            |
|date: 2001/06/14 18:29:25;  author: astro;  state: Exp;  lines: +3 -10                                                                   |
|Fixed a few links.                                                                                                                       |
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|revision 1.23                                                                                                                            |
|date: 2001/06/14 18:19:24;  author: astro;  state: Exp;  lines: +8 -4                                                                    |
|Added a few more general search engine links for specific queries about Astronomy Software Linux                                         |
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|revision 1.22                                                                                                                            |
|date: 2001/06/14 18:14:34;  author: astro;  state: Exp;  lines: +13 -3                                                                   |
|Added some general search engine links for specific queries about Astronomy Software Linux                                               |
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|revision 1.21                                                                                                                            |
|date: 2001/06/13 22:06:47;  author: ecdowney;  state: Exp;  lines: +4 -4                                                                 |
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|revision 1.20                                                                                                                            |
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|revision 1.19                                                                                                                            |
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|*** empty log message ***                                                                                                                |
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|revision 1.18                                                                                                                            |
|date: 2001/06/13 16:49:06;  author: astro;  state: Exp;  lines: +4 -4                                                                    |
|Changed the Copyright to include the year 2001.                                                                                          |
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|revision 1.17                                                                                                                            |
|date: 2001/04/10 21:47:17;  author: astrohowto;  state: Exp;  lines: +4 -4                                                               |
|Changed www.astronomy.net to astronomy.net.                                                                                              |
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|revision 1.16                                                                                                                            |
|date: 2001/04/10 21:43:43;  author: astrohowto;  state: Exp;  lines: +0 -2                                                               |
|Removed log message.                                                                                                                     |
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|revision 1.15                                                                                                                            |
|date: 2001/04/10 21:42:56;  author: astrohowto;  state: Exp;  lines: +5 -3                                                               |
|Added Log information.                                                                                                                   |
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|revision 1.14                                                                                                                            |
|date: 2001/04/10 21:40:14;  author: astrohowto;  state: Exp;  lines: +4 -4                                                               |
|Changed main HOWTO web site to howto.astronomy.net.                                                                                      |
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|revision 1.13                                                                                                                            |
|date: 2000/11/28 15:23:37;  author: astrohowto;  state: Exp;  lines: +6 -4                                                               |
|Revised the Author information.                                                                                                          |
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|revision 1.12                                                                                                                            |
|date: 2000/11/21 22:00:45;  author: astrohowto;  state: Exp;  lines: +16 -4                                                              |
|Added Projects section and added CHARA to it.                                                                                            |
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|revision 1.11                                                                                                                            |
|date: 2000/11/21 21:39:11;  author: astrohowto;  state: Exp;  lines: +14 -7                                                              |
|Added several links and removed one bad one for AstrHorloge.                                                                             |
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|revision 1.10                                                                                                                            |
|date: 2000/11/07 17:22:16;  author: astrohowto;  state: Exp;  lines: +220 -225                                                           |
|Removed a few more text line ending problems.                                                                                            |
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|revision 1.9                                                                                                                             |
|date: 2000/09/21 15:55:48;  author: astrohowto;  state: Exp;  lines: +4 -4                                                               |
|Changed the link to XSky after receiving an email from terry Friedrichsen.                                                               |
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|revision 1.8                                                                                                                             |
|date: 2000/08/14 18:33:47;  author: astrohowto;  state: Exp;  lines: +12 -3                                                              |
|Added Nightfall to plantarium programs.                                                                                                  |
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|revision 1.7                                                                                                                             |
|date: 2000/08/14 18:16:28;  author: astrohowto;  state: Exp;  lines: +38 -62                                                             |
|Removed line feeds from several of Elwood's paragraphs.                                                                                  |
|Also added a few suggestions from emails received.                                                                                       |
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|revision 1.6                                                                                                                             |
|date: 2000/05/03 22:01:25;  author: astrohowto;  state: Exp;  lines: +15 -3                                                              |
|Added Copyright text.                                                                                                                    |
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|revision 1.5                                                                                                                             |
|date: 2000/05/02 11:59:19;  author: astrohowto;  state: Exp;  lines: +8 -4                                                               |
|Added Linux to the Title and added some contact information. JSH.                                                                        |
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|revision 1.4                                                                                                                             |
|date: 2000/05/02 09:05:20;  author: astrohowto;  state: Exp;  lines: +224 -110                                                           |
|Elwoods additions.                                                                                                                       |
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|revision 1.3                                                                                                                             |
|date: 2000/04/30 15:14:25;  author: astrohowto;  state: Exp;  lines: +4 -3                                                               |
|More RCS                                                                                                                                 |
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|revision 1.2                                                                                                                             |
|date: 2000/04/30 14:45:16;  author: astrohowto;  state: Exp;  lines: +5 -0                                                               |
|Added some RCS keywords.                                                                                                                 |
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|revision 1.1                                                                                                                             |
|date: 2000/04/30 14:43:43;  author: astrohowto;  state: Exp;                                                                             |
|Initial revision                                                                                                                         |
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