******  Polaris 3.1  ******

Presenting Polaris    

Polaris is a shareware package for the Psion series 5/5mx. It was written for star gazers and amateur astronomes who want to know which celestial bodies are visible from a chosen spot, at a given moment in time.

Polaris establishes a map of the sky at a specified height from any viewpoint and supplies alt-azimutal markers.
Reminder :
Altitude or height is given in degrees ;
0° = Horizon
90° = zenith.
The azimuth is the horizontal direction.
      0° = North
   90° = East
180° = South
270° = West

Several zoom factors are available (0-15), allowing the user to select different sized portions of the sky. The database includes the principal stars and their proper names for constructing the constellations, the secondary stars, the 110 Messier objects and a planetary position calculation module.

A new module was added to the version 1.1 which allows the user to edit and manage some files of celestial bodies. Each map is vectorially calculated from the information contained in the database. This implies a lot of work for the CPU, and takes some time, but gives the user access to very powerful functions and a constant precision
independent of the chosen zoom factor.

The 3D projective view of celestial sphere allows a correct azimutal representation of sky and constellations patterns. To take the weight off the CPU during calculations, Planetary positions are given to the nearest 0.2° and sunrise sunset times are given to the nearest 3 minutes, which is OK for this application whose goal in life is to satisfy such questions as ; "What will I look at tonight or next week in a given portion of the sky ?"

 Polaris features functions normally available only on more powerful machines (such as a PC, etc.), including :

• Point and click interface to obtain celestial and alta-azimutal coordinates of any object or point on the screen.
• A viewpoint which can be moved towards an object, planet, etc.
• Choice in what should be shown on a given map.

To try out Polaris, load the sample view ' Planet conjonction March 2000 '  and go towards the MOON.

Installing Polaris 

Distribution Files : 
POLARIS.SIS  program installer french/english.
OPTION.SIS    optional file, see further in the text.
Lisezmoi.rtf 	french manual
Readme.rtf 	this file.

Just click twice on POLARIS.SIS file from you PC if you have PsiWin installed or copy the file on the Psion and run it. You'll be prompted to choose langage and other installation options.
 
The following files are  catalogues of celestial bodies which are of some interest for an amateur astronomer equipped with only simple binoculars or more powerful instruments. They are copied by default in the program directory

•NGC_12.FIC  a selection of the New General Catalogue of objects such as galaxies, clusters and nebulae with magnitude brighter than 12.0. It contains 1854 objects but if you are interested by fainter objects the installation file OPTION.SIS proposes you NGC_15.FIC which contains 7474 objects up to magnitude 15.0.
• CONSTELL.FIC ( by Eberhard Rompf) displays constellations names.
• STARNAME.FIC ( by Eberhard Rompf) displays some major stars names.
•DOUBLE.FIC a catalogue of more than 1500 double stars which responds to these criteria:
–the main star have his magnitude <= 6.0
–the second star have his magnitude <=13.0
–the distance is >= 1 Arcsec
–the distance is <= 2 Arcmn
•Some comments have been added to achieve easy filtering of interesting pairs (see Abbreviation section in the help file)

The extension '.ORB' is used for comets & asteroids Orbital elements. Next files are to be copied depending of your interest and of the available space on your disks.
•COMET.ORB contains some recently observed comets including Hale Bopp is copied by default .
•ASTER100.ORB  contains 238 asteroids of  dimension more than 100 Km will be copied by default.

if you run the installation of Option files

ASTER50.ORB  contains 688 asteroids of  dimension more than 50 Km.
ASTER10.ORB  contains 1766 asteroids of  dimension more than 10 Km.

If you are interested in comets and asteroids you can browse on my web site :
http://members.aol.com/achay/index.htm.

There are useful links to often updated databases of orbital elements and particularly to TED BOWELL's site where daily updated asteroids elements are available,  I also provide some tools to read these files and to translate them to Polaris ORB file.

Using Polaris
  
Important: most of the subjects explained here are included in the help file provided with the program

General 
  
The Screen
Polaris draws a 640x640 pixel chart, this speeds up the program by avoiding rezooming, and also provides a more natural square chart especially a nice whole sky view. The Psion screen displays a 640x240 pixel zone of this chart, so you have to scroll the display to see the entire chart.
'Up and Down' arrows scroll the screen.
'PgUp' and 'PgDown' combinations goes to the upper and downer zones.
'Enter' key goes to the central zone.

Keyboard and Hotkeys
The use of 'Ctrl+key' combination is not necessary but works, to access hotkeys type directly the desired key or 'Cap'+key combination.

Scroll bar
The scroll bar at the left indicates the current relative displayed zone. 

Cursor
Some commands require you to click at a point on the screen, a flashing cursor then appears. You can move it with the arrow keys. Press ' Enter ' to confirm or ' Esc ' to cancel the current command and hide the cursor. You can also just point on the screen with the Pen. After some commands it stays on the screen in a ' static ' form to let you remind the last point entered.
'Esc' key also hides it after a 'Show with cursor' option in 'Search' command.

Menu  Files 

Catalogue
 Description:  search, read and edit items of a collection of celestial bodies. In the main window the first line displays the name of the current item, the second one displays its screen name. In the small rectangle are displayed: the name of the current file, the rank of the current item  and the total number of items. The following commands are available:
"<-" Moves to the previous item.
"->" Moves to the next  item.
"Tab" Searches for a string in all files.
"+" Continuous search.
"E" Edits the current item.
"Esc" Returns to sky window and saves the current file.
"Del" Deletes current item, be careful, as no confirmation is asked.
"N" Edits a new item.
"Menu" Displays a short menu with some options: open  another file of object, save the current with a different  name.

Comets and Asteroids
This allows you to manage some files of Orbital elements used to compute comets or asteroids positions. You can add new objects like incoming comets or update asteroids orbital elements. (see Iras subject on my web site).
The edition of orbital parameters varies depending on what data are available. The four major cases are:

1) The time at Perihelion is known:
a) It is given in julian date format and can be typed directly.
b) the format is Day Month Year and Time: leave this value to 0 and fill the other fields. When saving an additional dialogue will allows you to enter the date. The 'Mean Anomaly' must be ignored.

2) The time at Perihelion is unknown:
Leave this value to 0. When saving additional dialogue lets you enter a 'Mean Anomaly' value and the Date at which it is computed. Note that in this case the Semi Major Axis must be known.

3) The distance at Perihelion is given:
Fill this field and leave 'Semi major Axis' to 0.

4) The semi major axis is known:
Fill this field and leave 'Distance at Perihelion'' to 0.

View
You can load a previously saved view or save the current one. When loading one you are asked if the saved time must be used (i.e.  an eclipse view needs to recover the saved time) or if the current time must be used (i.e. South view at zoom 3 at home) .

Printing
Prints the current view. The poor definition of the screen comparing to printer's give a so poor result but I study a way too have a better print output.

Registration
Allows input of user's code and name for access to the non-limited version.

About
Presentation screen with version and registration status.

Quit
Leaves Polaris.

Menu Settings

Starting
Allows you to set the starting parameter like: Location, Catalogue file, zoom and direction, 'Show' options etc...

Date &Time
Allows input of the observation time, a 'Now' option sets it to current time and date. The "Autom" option forces display update calculations every 6 minutes (available only when time is set to "Now").

Location
Allows 'Load', 'Edit' and 'Create' commands for Location .
Longitude and latitude values are expressed in decimal degrees.

• Longitude East is expressed using positive values.
• Longitude West is expressed using negative values.
• Latitude North is expressed using positive values.
• Latitude South is expressed using negative values.
• DTU indicates the difference (expressed in hours) between local time and GMT.
Daylight saving time must be set to 'Yes' if you want Polaris to take account of it, you may save the same location with two different names and one with this option active and not active for the other like 'Paris winter' and 'Paris summer'.

Show
Allows choice of which objects to show/hide on the display. Some have only 'Yes,No' choice but some have a third choice:

'Constellations' + 'Stars' : draws Constellation stars but not their patterns
'Grids' + 'Horizon': draws only the horizon line (in black).
'Catalogue' +'Filter': This option allows you to define a filtering of catalogue objects by magnitude and string search. If selected an additional dialogue lets you edit these values after ending the 'Show' command. How works the filter ? It displays only objects that match an upper limit magnitude and that contains a string. (i.e. To display only Open Cluster brighter than 10.5 Mv type 10.5 and 'open' and choose 'Clusteng.fic' as catalogue file)

Centre
Requires user to click with the cursor at a point on the screen and centres the view on this point.

Zoom
Requires user to click with the cursor at a point on the screen and then to select a zoom factor (1 to 15).

Status
This gives you the current status: current time (the time used for computation, not necessarily the real one ),
the current location, the catalogue and comet/asteroid files.

Orientation

'North, East, South,West
Standard views along these directions at 25° above the horizon (the black line) and with a 150° field.

Zenith
Standard zenital view with 180° field.

Direction
Observation direction and Zoom factor can be specified here in azimuth and height.

Search
This command allows you to find various types of objects and centres the display on them. In some situations the requested object already lies on the screen, thus, to avoid a display refreshing and spare time, a 'Show with cursor' option is supplied. 

Planet
Centres the map on a planet, i.e. 7 planets + sun + moon

Constellation
Centres the map on a constellation: an interface lets you 'navigate' through the constellations or search a name in the database: ex. input 'Bear' will return "Great bear" and "Little Bear " ...). See 'Catalogue' for commands.

Messier
Centres the map on an object from the Messier Catalogue: M1 to M109.

Catalogue
Centres the map on an Object from the catalogue file like the Ngc_12.fic.
Star
Centres the map on a star, if you know the name of a star you can find it on the map or just go through the database by the arrow keys. If you press ' Ctrl' while pressing the arrow keys you may jump to the next or previous constellation. See 'Catalogue' for commands.

Menu Info

Ephemeris
The ephemeris of Planets, Sun and Moon or Asteroids and Comets are given for the current date. For asteroids and comets the ephemeris concerns the current object, additional dialogues allows you to change the current one.

Constellation
Requires user to click with the pointer at a point on the screen and returns the name of the nearest star giving its name, the constellation to which it belongs, its visual magnitude and equatorial coordinates for the current epoch.

Coordinates
Requires user to click with the pointer at a point on the screen and returns the equatorial coordinates of the point, and also the culmination, rising and setting times in Local Time.

Azimuth
Requires user to click with the pointer at a point on the screen and returns the azimuthal coordinates of the point.

Jovian Moons
This displays three windows. In the right one and the upper one Jupiter is drawn and its four major satellites. In the third one the available commands are grouped.

' Polar view ' displays a view of Jupiter's moons perpendicularly of their orbital plane. This is to appreciate the orbital distances that are scaled with Jupiter diameter. The arrow indicates the direction of the Earth.

' Terrestrial view ' offers a realistic view of these objects seen from the Earth.

The command window offers:
'I': this toggles between direct or inverted terrestrial view. ( most astronomy optics invert the vision, but binoculars made for terrestrial use don't).
'D':  allows to change the date of computation.
'Up' and 'Down': change the time increment value used by animation features ( 30mn, 1h, 6h, 1 day, 4 days).
'Right' and 'Left': applies time increment or decrement.
'F' and 'B': starts a forward or back animation.
'Esc': return to Polaris chart.

Differential
This feature is useful for those who have a scope equipped with Right Ascension and Declination circle but no pointing computer. It asks you to point out a reference point ( a bright easy to find star) and to point at a desired object, the difference of the celestial coordinates are then given.
Note: a positive difference of Declination means ' Norther' and positive difference of Right Ascension means in the diurnal way.

Symbols
Shows the symbols used for displaying stars and planets.

Specifications

• The valid range for computation dates is from the 1st of January 1901 to the31st of December 2079 (Registered Version).
• Accuracy of Planets position 0.2° for R.A. and 0.06° for Declination.
• Accuracy of Moon position 0.2° for RA and 0.06° for Decl.
• Accuracy of Sun position 0.01° for both RA and Decl.
• 780 Stars in the constellations database.
• 16000 secondary stars for magnitude  equal or brighter than  7.0
• Time required to display objects : 1s for 160 Obj. approx.
• The formats accepted by the database for coordinates are:
       Right Ascension: 23.4567h or 23h 27.67 m or 23h 27 m24s (Unused spaces are deleted)
       Declination: 23.25° ou 23°15' or 23°15' 15" (Unused spaces are deleted)

Shareware  

This program is shareware, you can distribute it as a ZIP archive as long as nothing is removed, added or modified. I decline any responsibility for any result of use of this program, although I think that the worst that could happen to you would be making a balls up of a photo of your favourite Nebula!

Polaris is equipped with all features in the shareware version, so you can try it out as much as you feel. The only limit is that the date of calcul only goes between the 1 rst of January and the 30th of May 2000 To go beyond these limits, just send me a user name of at least 5 characters long and the ID number the registration dialogue gives, together with the sum of 20US Dollars, or equivalent in French Francs, UK Pounds, in cash or a 150 FF Euro-cheque to the following address :

Achay Doan
2 Av Edouard Vaillant
92150 SURESNES
 FRANCE

I will send you your code in return by email.

You can also leave me a message  at achay@aol.com .
Feel free to let me know of any remarks and suggestions you might think of.

Special thanks to

Didier Cabuzel from Psion Club France, who helped me for the version 1.1.
Eberhard Rompf who is my first registered and enthusiast user, and has supported me a lot in elaboration of version 1.2, assuming the Beta testing and do the German translation. 

Have fun !     Achay Doan

date 22/05/2000