•Astro Info


"Astro Info" displays some basic information useful to star gazers, such as Sun Rise and Set, Moon Rise & Set and % Full, and the rising and setting of each of the 8 planets. (Yes, eight.  You didn't expect us to include the Earth, did you?) In addition, Astro Info 2.0 and later features support for catalogs of deep space objects, such as clusters and galaxies.



•Requirements


"Astro Info" requires at least PalmOS 2.x.  You will also need a doc reader, such as AportisDoc, if you wish to read the "location.pdb" file.



•Included in this Version


Required to Run Astro Info:

Astro-xx.prc: The Astro Info program 

Optional Databases:

dstrules.pdb: A list of rules for daylight savings time.  It contains predefined rules for most regions.  If you don't install this, AstroInfo can't use daylight savings.

Stars.pdb: A catalog of bright stars up to magnitude 5.00. Stars are identified by their constellation, Beyer letter, and SAO number.  It is highly recommended to install this, if you want to use the "Sky Map" feature.

Caldwell.pdb: The Caldwell Catalog - A list of 109 celestial objects designed for amateur astronomers. Objects are identified by their Caldwell and NGC numbers.

Messier.pdb: The Messier Catalog - The classic list of famous stellar objects.

Optional Documents: 
You can read these documents on Palm with a DOC reader.  These documents are also available in plain TXT format to read on PC.

Astro.pdb: This document. 

Location.pdb: A list of cities and their latitude and longitude, in DOC format.

License.pdb: The Gnu General Public License - This license governs the copying and distribution of Astro Info.


•Configuring Astro Info


To use "Astro Info", you need to first tell it your position and your time zone.  To do this, start "Astro Info", and select "Options" from the menu.  Enter your Time Zone as how many hours off of GMT you are.  Remember to use the switch to specify a western time zone vs. an eastern time zone. For example, some one in Berlin would use a TZ of "1h00mE" while someone in California would use "8h00mW". 

Don't forget to choose your daylight savings time rule. We included daylight savings rules for all regions which have a simple rule based on the Gregorian calendar.  Look at the file dstrules.txt for the exact rules.  If you find inaccuracies look at the end of this document for the procedure to report a bug.  Israel doesn't use a rule so we only have the right values for a single year.

Next, set your latitude and longitude, in degrees and minutes. Remember to check the boxes for the southern and western hemispheres as needed.

And that's all there is to it! If you don't know your latitude and longitude, check out the "location.txt" or "location.pdb" file and find the city that's closest to you.  FIXME: Add DST rules for these cities and provide a way to select the city directly in the option dialog.

Color Support

If you install Astro Info on a color Palm, you will have an extra menu entry. This entry, called "Night Mode" allows you to toggle the color scheme of the entire Palm from full-color to red-on-black: just the thing for using your Palm at your telescope!  Night Mode doesn't currently work with the latest color devices.


WARNING:

If you turn on Night Mode, then delete Astro Info, you will not be able to restore the default colors without doing a hard reset!!!



•Using Astro Info


Setting the Date and Time:


Astro Info does not use the current date and time for it's calculations. All Astro Info displays have buttons to set the date and time at the top. To get the current date and time, press the "Now" button. To quickly see tomorrow or yesterday, use the arrow buttons.  To set the time or date, press the appropriate button and the standard date or time dialog box will appear.



Using the Various Pages:


All Astro Info pages have a online help.  Choose the Help option from the menu.  When you're in a dialog, press the info button in the title line.

Most Astro Info pages have the time controls to select another date or time.  Just click on the date or time field or the now button.

The Solar System page shows rise and set times for each of the other 8 planets. You can also click on the name of a planet, which will pop-up a dialog box showing the planet's current coordinates.

The Catalog page is new to Astro Info 2.0. This page displays a list of astronomical objects, such as the Messier List or the Caldwell Catalog. Clicking on the name of an object will pop-up a dialog box showing the object's magnitude, size, rise and set times and it's current position in both equatorial and alt/az coordinates. To select a new catalog, click on the Select button.

For each object there is a Details page that shows its astronomical data.  You can reach it by selecting that object in the Solar System page or the Catalog page.  The information shown slightly differs for each planet, see the web pages for more details.

The Other Timebases page converts the time and date to various other astronomical time systems.

The Sky Map is new to Astro Info 2.3.  This page shows the selected Star Catalog, the Sun, the Moon and the planets as seen at the current Location at the selected Date and Time. Initially the view is centered on the last selected object.  You can zoom in and out with the Page Up/Down Buttons and you can move the view with the pen. Clicking on a star or planet will select it and show its name.  The 'i' button in the title bar shows the detailed information.


Creating New Catalogs


The good news is, yes, you can. The bad news is that you need to be able to use Java applications. If you have a special interest in creating your own catalogs, drop us a note at astroinfo-discuss@lists.sourceforge.net



•Reading the Numbers


When looking at rising and setting times, you should remember that they are always in the context of the currently selected time.  Some of these times are for the previous or following day.  In that case they are marked with a '+' or '-' sign.  A small circle denotes that the daylight savings time is effective.

And a quick note to users of the old PalmOS 3.0 - some of you have noticed that when you push the "Now" button, the time gets rounded down to the nearest five minutes.  The reason for this is that the 'time selection' dialog only lets you set the time to 5 minute intervals.  For consistency we decided to place the same restriction on the "Now" button.



•Notes on Accuracy


I've tried my best to make these figures accurate.  For the most part, I've succeeded - "Astro Info" results are generally within a few minutes of the results of commercial astronomy software like "SkyMap".  The largest loss in accuracy in "Astro Info" comes from simply estimating the positional errors introduced by atmospheric distortion and from assuming that the observer is standing at sea level.  Smaller losses in accuracy come from failing to compensate for perturbations in planetary orbits (caused by the other planets).  None of these problems cause more than a very small shift in position. 



•Further Reading


"Practical Astronomy With Your Calculator" by Peter Duffett-Smith. (ISBN 0-521-35600-7)



•Version History

3.1
- Fullscreen support for 320x480 devices.
- Constellation lines displayed.
- Performance improvements for ARM devices.
- Customisable color preferences.
- Hipparcos catalogue containing more than 100000 stars.

3.0
- Improved support for grayscale/colour devices.
- Hires support for PalmOS 5.0.
- Improved handling of catalogues.
- Calculation performance and accuracy improvements.
- Planet images displayed in Sky Map.
- Tighter integration between all forms.
- Improved phase drawings for solar system objects.
- More information on objects.
- Extensive customisable preferences.

2.5.1
- Support for PalmOS 5.0
- Fixed rise/set times for stars.

2.5
- Sky Map displays the current Alt/Az coordinates
- Russian translation.
- Fixed bugs.


2.4 beta
- Better connectivity through the small title buttons.
- More information for planets: fullness, phase angle, distance.
- Fixed rise/set calculations for Moon (they were off by several minutes).
- Transit time.
- Handle circum polar planets.
- Phase images for Moon and planets.
- Most preferences are now preserved when upgrading.

2.3.1
- Fixed bugs.

2.3
- Calculations are now done with fixed point numbers, which is much faster.
- The Sky Map feature was added.
- Support for daylight savings time was added.
- Fixed the other bugs with lat/long settings between 0 and -1 degrees.

2.2 beta
- Updated the documentation
- Corrected a bug where, if you used AM/PM time formats, some times might get chopped short.
- Added the Bennett Catalog (a southern hemisphere catalog like the Messier or Caldwell catalog). Donated by Jeff Burton. Thanks Jack!
- Fixed a bug in the lat/long settings that caused problems with positions between 0 and -1 degrees latitude or longitude.

2.11 ga

Same as 2.11 beta, with new HTML documentation.

2.11 beta

Added a new feature! Now, when looking at the planetary information screen,
planets that are above the horizon for the current time will be shown in
bold.

2.10 beta

This version corrects a major bug in 2.00. Basically, if you delete the catalog that Astro Info currently has open, it would crash the Palm every time you start it, until you deleted and re-installed Astro Info. This has been corrected.

In addition, I've made a major change in how Sun Rise/Set and Moon Rise/Set are calculated. In previous versions, both these functions used an interpolation step to improve accuracy. Unfortunately, this step could also cause weird behaviour. To correct this, Sun Rise/Set now calculates the celestial position of the sun at local noon, and then uses that to estimate the position of the sun at rise and set time.

Because the moon's motion varies so much, this approach does not work for it. Instead, the initial estimate of the moon's position is used to approximate the rise and set times. At that point, each time is used in an iterative loop: (A) Where was the moon at time X? (B) At what time would the moon rise (or set)? Set X to the rise (or set) time and go back to (A). This loop repeats until X stops changing, typically three or four times, and the loop is done for both rising and setting. This means that Moon Rise/Set now takes about eight times as long to calculate as it did in 2.00. But the good news is that I think this completely eliminates all the bug reports about weird values for Moon Rise and Moon Set.




2.00 gold

No feature changes over the beta version. Additional catalogs were added.




2.00 beta

Catalog Support!




1.20

Color Support!

Now, when installing a new version of Astro it deletes the old preferences. Because of a quirk in the way form ID's are handed out, every time I add a new dialog box or page to AstroInfo, the old preferences cause problems. So, now I just whack 'em.





1.10

Added positional information to the Lunar and Solar information panels.  

Switched from using an interpolation step in calculating Moon Rise/Moon Set to directly calculating the Moon's position both times.  This seems to have improved the Moon Set time somewhat, although the error is still unacceptably large.

A lot of internal changes were made to the code to improve "Astro Info"'s coding style and to make it a better behaved PalmPilot application.





1.05

Significantly increased the accuracy of Planetary Position information by switching to using an iterative approximation of Kepler's equation instead of using a simple first order approximation.  The downside is that this causes a slight decrease in performance.  Still looking for the source of the discrepancy in the Moon Set time.

Also added an Alt/Az information display for the planets.  To see the current position of a planet, click on the name of that planet.

Astro Info now remembers what it was displaying the last time you ran it and returns to that display automatically.

A number of minor code glitches have been corrected.  For the most part they were harmless, but they could cause you to run out of memory if you ran Astro Info for a very long time without ever exiting the application. (PalmOS did clean up the leaking memory on exit, so there was no problem with Astro Info 1.02 trashing memory - as long as you exited the application every now and then.)





1.02a

Same code as 1.02; includes expanded documentation and location files.




1.02

Users instantly discovered that the Latitude and Longitude fields could not be set to negative values.  (This is because PalmOS does not recognize that '-' is a legitimate numeric character.)  I fixed this by adding a check box next to each option. Select the check box when entering a negative time zone (West of GMT), a negative latitude (below the equator) or a negative longitude (West of Greenwich, England).  




1.01

Initial Release




•Copyright


"Astro Info" is copyright 1998-2003, Michael Heinz, Jochen Hoenicke, Peter Enzerink. All rights reserved.  However, both the "Astro Info" and the source code for "Astro Info" have been released under the Gnu General Public License. Please see license.txt for more information.

All the formulas used in "Astro Info" are derived from the book "Practical Astronomy With Your Calculator" by Peter Duffett-Smith.



•Bug Reports


So, you think we care about your problems, eh?  Well, yeah - if you have a problem or a suggestion for an improvement, visit the SourceForge pages: http://sourceforge.net/projects/astroinfo.  Please use the bug, support or feature request trakker. If you absolutely don't want to use this send a mail to our mailing list, see below.

Note: We're actively recruiting volunteers to help improve Astro Info. If you'd like to help, drop us a line!  You can contact us at astroinfo-discuss@lists.sourceforge.net .
