
                            S O L U N  3

                    An Astronomical Application
                       for the Psion Series 3

                     *** User Documentation ***

                           David Rushall

                                1995

==What is Solun?==

Solun is an astronomical tool, aimed as a convenient and educational
aid to the amateur astronomer, and provides both almanac and
planetarium functions.

New features in Version 3 include: high-resolution graphics on the
Series 3a; lunar month and rise/set reports; chart object
identification; primitive animation; and, a number of other
improvements and bug fixes.

Solun should run on the Psion Series 3 and 3a machines. A minimum of
256K is recommended, although it may be possible to run a partial
installation on unexpanded 128K machines. (It may also run on Acorn
Pocketbook machines, but this has not been confirmed.)

This version of Solun is shareware.

One-line package description:

     S3/S3a Planetarium, almanac, etc (now: S3a graphics, share.)

==Conditions of Use==

Solun is shareware and copyright; it is _not_ public domain. The
rights to this package remain the property of the author, although
it may be distributed and used according to the following
conditions:

   1) Use of this package is entirely at the user's own risk. The
     user must accept responsibility for any direct or indirect loss
     or damage arising from the use (or misuse) of the package.

   2) This package exists in two forms: unregistered and registered.
     The public distribution consists of the unregistered version,
     which may be used for a indefinite period. However, if you make
     regular use of the package, you might like to consider
     registering your copy, and obtaining additional functionality.
     For details how to register your copy please see the section at
     the end of this document.

   3) Both the registered and unregistered versions are supplied
     `as-is' and no warrantee is given of any kind. Registration of
     the package does not provide any additional rights, with the
     exception of the right to keep a copy of and make use of the
     registered version, according to these conditions.

   4) Distributions of the unregistered version should consist only
     of the complete files of the original `*.zip' archive, and
     should not be altered in any way.

   5) The unregistered version is not for sale. However, it may be
     distributed as part of a commercial transaction, provided: the
     fee charged in the transaction is no more than to cover costs
     and a modest handling charge; and, it is made clear in the
     terms of the transaction that the customer is not purchasing
     the package but obtaining access to shareware software which
     may require a further fee to be paid to the author.

   6) The registered version should not be distributed in any way
     and may only be used on one machine at a time. Special
     conditions for multiple user licenses for worthwhile
     institutions (such as schools and enthusiast groups) will be
     considered on application.

All trademarks used in this document are acknowledged.

Note: Some of the files provided along with the Solun application
are derived from the Yale Bright Star Catalogue and as such are
_not_ covered by this declaration of copyright and these conditions.
These files are identified by their `*.str' and `*.sol' suffixes,
and are provided separately. The original Yale Bright Star Catalogue
may not be used for commercial purposes without express previous
written consent from the Department of Astronomy, Yale University.

Warning: Both the plotted positions of `fixed' objects and the
calculation of the objects of the Solar System are not necessarily
accurate. Whilst these may be sufficient for most amateur
astronomical purposes, Solun should _not_ be used for navigation.

==Installation==

--Migrating from a previous version of Solun--

Since some of the file formats have changed, the safest way to
migrate from a previous version of Solun is to simply delete all the
old files (after making a backup) and install the new version from
scratch. You must also remove the old `Solun' icon from the `System'
screen and install the new one.

Note: You _can_ keep and use any `*.lab' label files you may have
created.

After installation, you should find the new version easy to get used
to, and notice a number of improvements. Please see the history
section below for more details.

--List of files--

Solun is a fairly large package, at least in Series 3 terms, but you
may chose not to install certain files at the cost of limiting
functionality. This allows an amount of tailoring of the package to
suit your taste and resource availability.

A minimal installation must contain of the following files:

   \APP\Solun30.opa (or \APP\Solun30a.opa)

   \APP\SOLUN\Flutils.fl0 (or \OPO\Flutils.fl0)

   \APP\SOLUN\Solun.pic

The following files must be installed for the world map, globe and
orrery displays:

   \APP\SOLUN\Solunpln.opo

   \APP\SOLUN\Solun.mpa (not required for orrery display only)

The following file is required for the simplest star chart (sun,
moon, planets, equators and grid lines only) and globe displays:

   \APP\SOLUN\Soluncht.opo

When added to the basic star chart support, the following files
allow the display to include `fixed' objects, such as stars.

   \APP\SOLUN\*.sol
     Contents: Stars.sol - 2000 stars; Messier.sol - 140 galaxies,
     nebula and clusters; Const.sol - constellation outlines;
     Bound.sol - constellation boundaries.

The label files allow a star chart to be annotated with textual
labels:

   \APP\SOLUN\Solun.fon

   \APP\SOLUN\*.lab
     Contents: Const.lab - full names of all 88 constellations;
     Keyconst.lab - abbreviated names for some well-known
     constellations; Scale.lab - right ascension and declination
     labels.

When used in conjunction with the `fixed' object files, the
following files allow the identification of these objects via a
`point-and-click' interface (registered version only):

   \APP\SOLUN\*.str
     Contents: Messier.str - info for objects in Messier.sol;
     Yale.str - info for first 500 objects in Stars.sol (down to
     about 4th magnitude).

The following files supply user documentation and general
information:

   \APP\SOLUN\Solun.hlp - online help

   \WRD\Solun.wrd - this file (also supplied as a flat text file in
     Solun.txt)

Finally, the unregistered version includes a demonstration of the
graphics of Solun for the Series 3a. These files are only required
for the demonstration, and can be deleted at any time.

   \APP\Solun3ad.*

Note: In addition these files, Solun may create two further files in
the directory M:\OPD\ - `Solun.ini' contains the user settings for a
number of functions, and `Solun.dat' is used for chart drawing.
These are fairly small and can be deleted at anytime, if wished.

--Copying the files onto your Series 3--

After you have decided what functions you require, copy the required
files onto your Series 3.

Solun will look for its files on both the internal disk and the two
SSD devices (M:, A: and B: - in that order), and will use the first
copy it finds. If you wish, you can install some of the files on one
disk and some on another. However, the files must be in the correct
directory:

   Solun30.opa or Solun30a.opa in \APP\

   Flutils.fl0 in \APP\SOLUN\ or \OPO\

   All other files in \APP\SOLUN\

Note: `Flutils.fl0' is a shared library used to support my OPL
programs. You can simply place the supplied Flutils.fl0 file in the
\APP\SOLUN\ directory. If you have other applications which use the
library and you wish to only have one copy of Flutils.fl0 installed
on your system, you must place the highest version of Flutils.fl0 in
a \OPO\ directory (the version number of Flutils.fl0 can be found by
running the file from the `Runopo' icon).

Hint: If you have enough space, I recommend you install all the
files so that you can explore the various features of Solun. You can
always use the files list in the previous section to remove the
functions you don't need at a later date.

--Installing Solun onto the System screen--

Before you can start the Solun application, you must install the
application onto the System screen. See your Series 3 manual for how
to do this.

Install the application file, `Solun30.opa' (or `Solun30a.opa' for
the Series 3a version) and the `Solun3' icon should appear,
representing a view of the night sky through a telescope.

Hint: If you intend to use Solun a lot then you might like to assign
one of the application buttons to allow quick access. I find
<Control-World> particularly appropriate.

--The Series 3a graphics preview--

The unregistered version of Solun includes a brief preview of the
Series 3a version included in the registered package. Naturally,
this demonstration does not work with Series 3 machines.

To view the demonstration copy the five `Solun3ad.*' files into any
`/APP' directory and install `Solun3ad.opa' onto the system screen.
When run, the preview shows 4 screen-shots from the Series 3a
version. When you have finished viewing the demonstration, press any
key. You may then delete the `Solun3ad.*' files if you wish.

==Basic Operation==

--Starting Solun--

Solun is started by selecting the Solun icon on the `System' screen.
After a few seconds, you should see some brief messages, followed by
the Solun title screen.

--The windows--

Most of the functions of Solun operate on three windows, which
appear when Solun is started from the System screen. These windows
have specific functions:

   Main display window - the largest of the three, and occupying
     most of the screen, this is where Solun displays charts etc.

   Moon phase and information window - to the right of the main
     window, displaying a variety of things depending on the
     context.

   Time display bar - a single line of text along the bottom of the
     screen, normally showing the time and location used to draw the
     current display.

--Menus and key presses--

Note: In the following descriptions keys will be denoted using angle
brackets, <>. For example, <E> means the letter key `E', <Enter>
means the key marked `Enter', and <Psion-X> means press the `X' key
whilst holding down the `Psion' key.

In common with most applications for the Series 3, Solun is
controlled via a menu of options. This can be viewed by pressing the
<Menu> key, but individual options can also be selected directly by
pressing a `hot-key'.

Note: Unlike many applications for the Series 3, Solun does not
require the `Psion' key to be held down when pressing a hot-key.
However, Solun will accept <Psion>-key combinations if you prefer.

The options of Solun's main menu are split into six submenus, or
groups:

   Solun - contains the global controls, such as the observer
     location and time, and display update.

   View - the various displays that are available for the main
     display window.

   Chart - options controlling the view and detail for star charts.

   Info - contains a number of `almanac panels', displaying
     information about the objects in the sky.

   Key - symbol keys (or legends) for the symbols used on the
     displays.

   Special - miscellaneous options, such as saving the setup and
     quitting Solun.

Many of the options of Solun are controlled by dialogs, of which
most follow the usual conventions. However, a few of the dialogs
have slightly unusual behaviour and will be described in detail
where appropriate.

--The time settings dialog--

By default, Solun reads the time, date and time zone used for
displays and calculations from the Series 3 internal clock, and so
calculates and displays the current positions of objects. However,
the `Time settings' dialog, <T>, allows this default behaviour to be
overwritten.

The dialog is in two parts:

   o The first item selects the time zone to be used when displaying
     the time, such as on the time display bar. This can be either
     the current, local system time of the Series 3, or universal
     time (UT), which is equivalent to GMT. The selected time zone
     will appear on the time display bar, as UT plus or minus a
     number of hours.

   o The second item allows the choice between reading the display
     time from the Series 3 clock, or directly from the user. If you
     select user input, you can then enter the time and date you
     wish to display underneath, between the years 1970 and 2007.

Note: All calculations are based on the time shown in the time
display window, and _not_ the actual current time nor the time more
recently entered by the user. This allows a number of settings
dialogs to be altered before the main display is redrawn. To change
the time displayed, and hence the time used for calculations, you
must update the main display window. This can be achieved by
selecting a new view or updating the current view, <Space>. However,
since displaying a view can take some time, a special blank view is
provided, <0>, to allow the time to be updated immediately.

--Setting the observer location--

In addition the current time, many calculations require the position
of the observer on the surface of the earth. By default, Solun
selects the configured home city for the Series 3, as selected in
the `World' application, but you may choose to view from any city
that `World' knows about. The current observer location is also
displayed in the time display window.

To change the observer location, use the `Observer location' dialog,
<W>. This dialog has a slightly unusual behaviour, and is used a
follows:

   o To find a city, type the first few characters of it's name and
     press <Tab>. Solun will attempt to match this name, and display
     the first matching city found, or else return to the last city
     if there was no match. Note that, unfortunately, the dialog
     will temporarily disappear.

   o If you press <Tab> without altering the city name, Solun will
     step through the city database, displaying each in turn,
     alphabetically.

   o To return to the home city currently configured in `World',
     press <Menu>.

   o When your chosen city is displayed, press <Enter>. The dialog
     will disappear and the city will be used next time the display
     is refreshed (see the note in the previous section). Note that
     if you have just edited the city line, then pressing <Enter> is
     similar to <Tab>,  causing Solun to search the database.

   o If at any time you decide you do not wish to change the
     observer location after all, press <Esc>.

Hint: You may have noticed that this dialog does not allow you to
enter the latitude and longitude of locations directly. If you wish
to use a location not in the `World' database you must either select
a nearby city, or enter a new city into `World'. For example, I have
added cities for the north and south poles, using latitudes of +/-
89.0 degrees as an approximation.

--Turning sound on and off--

By default, Solun emits a short ring to let you know that a long
operation, such as drawing a chart, is complete. This can be useful
if you have switched to another application and want to know when
your request is complete.

If you wish to turn off this beep you can do so be selecting the
`Sound off' option on the main menu, <Z>. The same option may be
used to turn sound back on again, if you wish.

--Getting help--

Solun provides an amount of online information which is available
from the main menu:

   About Solun <A> - this displays information about Solun,
     including the version number and the author's email address.

   Symbols key <K>, <L> - describes the symbols used on the various
     displays in two pages: the first page <K> shows the sun, moon
     and star chart objects; and, the second <L> shows the symbols
     used for the planets.

   General help <H>, <Help> - Provides a quick reference to the
     functions of Solun and other information.

Note: The general online help is only available if you have
installed the help file, Solun.hlp, and is not context sensitive.
The online help only attempts to give brief descriptions of Solun's
functions, but does include a small database of useful information.

--Saving your setup--

You may save your current setup by selecting the `Save setup' option
on the main menu <Q>. This saves all the current settings, with a
few notable exceptions:

   o the type of the current main display;

   o the observer location, which defaults to the home city defined
     in the `World' application;

   o and, the time of the current display.

Your setup is saved in the file, M:\OPD\Solun.ini. You may delete
this file if you wish, provided that Solun is not running, but your
setup will be lost.

--Quitting Solun--

You can switch from Solun other applications by pressing one of the
eight application. If you do this, Solun continues to run in the
background, which is useful if you want to do something else whilst
Solun plots a chart, for example.

The Solun application can be closed in one of two ways:

   o from within Solun select `Exit' from the main menu, or press
     <Psion-X>;

   o or, from the `System' screen, move the cursor to the Solun icon
     and press <Delete>.

Alternatively, Solun can be forced to terminate at any time by
pressing <Psion-Esc>, from the Solun screen. However, this should be
considered as an emergency method only.

==The Main Display Modes==

The large window covering the majority of Solun's display is the
main display window. It is here that Solun displays it's primary
views: world maps, star charts and an orrery.

The display mode is selected from the `View' menu, or by pressing
one of the number keys (as detailed below). When a view is selected
in this way, Solun draws the view for the currently selected time.
The view may be later updated by pressing <Space>, or selecting the
`Update' option <U>, to account for the passing of time.

--The world map display--

The world map display shows an outline map of the world and
optionally overlays it with markers and shading to represent the
areas of the world in daylight or moonlight. When the map is
complete, a small flashing marker shows the current observer
location in the world.

The map is controlled by a number of items on the main `Options'
dialog, <O>:

   Sun marker - marks the current position of the sun over the
     world; that is the point on the earth's surface over which the
     sun appears to be directly above. This point may be marked in
     one of two ways: by the circular sun symbol used on the star
     charts; or by crosshairs drawn across the map.

   Moon marker - the moon marker marks the position of the moon in a
     similar manner to the sun marker, however there is no crosshair
     option.

   World map - this option controls the form of the world map
     display itself: a `plain' map displays just the map outline and
     the selected sun and moon markers; whilst the `day/night'
     version shades in the areas of the world that are currently in
     darkness, and also draws a line representing where the moon is
     rising or setting if the moon marker is switched on.

     In addition, this item controls another option of the world map
     display; the so-called `fixed' modes. These correct for a
     slight anomaly in the OPL line drawing function and result in a
     more detailed and slightly more accurate display, but at the
     cost of an increase in plotting time.

--Globe view--

Note: The globe view is only available on the registered version.

The globe view, <2>, displays a representation of the earth as seen
from above. The view shows the outline of the continents mapped onto
a sphere and overlays it with a representation of the dawn/dusk
line.

When the view is invoked a dialog is displayed to allow you to
select your view point: from the direction of the sun, the moon, or
a point directly above the observer's location.

Note: The globe view makes use of the star chart projection routines
- please see the note below about the star chart projection
sine/cosine tables.

--Star charts and planetarium--

Perhaps the most versatile of Solun's views, the star chart displays
the positions of various astronomical objects as they appear in the
sky. The star charts, <3>, are displayed in one of two modes:

   Star atlas mode - draws charts as pages from a star atlas. The
     views are centred on a particular coordinate in the sky and are
     orientated such that north is vertical at the centre of the
     screen.

   Planetarium mode - displays the sky as it would appear from the
     observer's location at the selected time. The view can be drawn
     with the observer facing in any direction, and looking at any
     elevation.

All star charts can show a range of objects at various levels of
detail, including: stars, planets, the sun and the moon; the
ecliptic, galactic and celestial equators; constellation outlines;
and, user definable labels. The control of star charts will be
discussed below.

Note: The star chart projection routines make use of a precalculated
sine/cosine table, which must be generated before a star chart can
be drawn. This process can take a few minutes, but once calculated
the table can be reused until Solun is terminated. In addition, you
are given the option to save the table to the internal disk. This
allows the table to be reused next time Solun is run and creates a
small file, M:\OPD\Solun.dat. If you wish, you can deleted this at
any time.

--The orrery display--

The orrery display, <4>, displays a representation of the planets'
progress in their orbits around the sun. There are two modes,
controlled from the main `Options' dialog, <O>:

   Stylised mode - in this mode, the nine planets are shown on a
     series of rings. Note that this view is not to scale; the
     planets' orbits are separated by a standard distance and the
     elliptical shape should be disregarded.

   Scale view - the scale view represents the relative distances
     between the planets, though not their relative sizes. Due to
     the distances of the outer planets, the view is shown in two
     displays: the left display shows the inner planets (Mercury,
     Venus, Earth, Mars); and the right display shows the outer
     planets (Earth, Mars, Jupiter, Saturn, Uranus, Neptune, Pluto).

In the stylised display, each planet is represented by it's
respective symbol, which are described on the legend, <L>. However,
the scale mode shows only small dots for the planets, and a small
square for the sun, due to space restrictions. Consequently, it can
be a little difficult to identify which planet is which, but this
can be resolved by comparison with the relative positions on the
stylised display.

--Null display--

As it's name suggests, the null display mode, <0>, displays nothing.
It is provided as a means by which Solun's clock (as shown on the
time display bar) can be updated without waiting for the main
display window to refresh.

This feature can be used to quickly display the moon phase or
consult the rise set times of objects for some date.

--The moon phase display--

The moon phase display depicts the phase of the moon, as seen at the
time and date shown on the time display bar. However, it is not
strictly one of the main display modes, but is displayed on the
information window in conjunction with the main display.

The display is controlled by the `Moon phase' option of the main
`Options' dialog, <O>, and can be configured to depict the moon as
seen from either the northern or southern hemisphere. It is
automatically updated when any of the main displays are drawn
(including the null display).

--Tracer plots--

The `Tracer' plots provide a primitive means of showing how the
position of the sun, moon, and planets change over time. They can be
used on either star chart or orrery views.

To use them, select the menu option, <G>, after your chart or orrery
is complete, and enter two values in the displayed dialog: the time
period between each individual plot of the object, measured in days;
and the number of periods you wish to plot.

When the dialog is completed, Solun plots the positions of the
objects for the specified periods, on the same display. If sensible
parameters are used, this results in a series of plotted positions
that can be traced to show the movement of the objects.

Note: When using this feature on a planetarium view, the positions
of the stars will not change. The tracer plots show the changing
positions of the objects against an apparently fixed background of
stars.

==Star Chart Configuration==

--Choosing your view--

As mentioned above, the star chart display has two modes: the atlas
and planetarium views. The `Chart view' dialog, <V>, is used to set
the type, direction and scale of star chart views. The dialog is in
two phases; first you select the mode, and then enter the mode's
parameters.

   Atlas (enter coordinates) - enter the celestial coordinates
     (right ascension (RA) and declination (Dec)) of a point in the
     sky, and the vertical field of view (FoV). The chart will be
     centred on the point specified, and scaled to show the
     specified field of view, in degrees, at the centre of the
     chart.

   Atlas (lookup labels) - selects an atlas view centred on a label
     (such as a constellation name) read from a label file (these
     files are usually used to draw text labels on a chart, see
     below).

     The dialog operates in a similar way to observer location
     dialog (see above): simply select a label file from those
     defined on `Chart labels' dialog (available from this dialog by
     pressing <Menu>), type the first letters of the label you wish
     to search for and press <Tab> to search or move on to the next.
     You can then specify the field of view, as before, and press
     <Enter>.

     Hint: If you wish to use a label file for the specification of
     atlas views it is a good idea to ensure the labels are
     alphabetically ordered when creating the file (see below), so
     that the `Next' function of the view selection dialog shows the
     labels in alphabetical order.

   Planetarium - unlike atlas views, this view rotates the chart to
     represent the sky as seen from the observers' location, when
     facing in a particular direction. The main parameters are the
     azimuth (or compass direction, eg. 0=North, 90=East, 180=South,
     270=West) and the altitude (the angle above the horizontal, eg.
     90=directly upwards) of the centre of the screen. As usual, you
     must also specify the field of view.

     There are also two other parameters to the planetarium view.
     The first of these sets the altitude of the horizon, which is
     drawn as a circle across the sky. This defaults to 0 (ie.
     horizontal) but can be adjusted to suit your location (eg. the
     view from a valley might be approximated by a slightly positive
     horizon, whilst the view out to sea from a cliff top might
     warrant a slightly negative value). The last item allows the
     selection of a `normal' or `compass' display: `normal' displays
     the sky as seen from the ground, whilst `compass' displays a
     mirror image, which when combined with zenith views (90 degrees
     altitude) may help to you judge the direction of individual
     objects.

Once the view settings are complete, the star chart will be
displayed next time you update the main display, with <U> or
<Space>, or explicitly draw a chart, with <3>. However, you might
like to review the level of detail first.

Hint: If you wish to stop a star chart once Solun has started
drawing it, you can do so by pressing a key, and answering `Yes'
when asked to confirm.

Another way to select a planetarium view is through the `Fast
planetarium' menu, <C>. This has a selection of preset views which
are drawn immediately, when selected. Eight of these views show the
sky with the observer facing each of the eight major compass points,
at an elevation of 30, and a FoV of 70. This results in each view
showing 180 degrees of horizon, albeit curved. In addition, there
are three zenith views: two at the same scale as the horizon views,
and are aligned north/south and east/west across the screen; and
another showing the entire visible sky as a single circle.

--Setting the level of detail--

The star charts can show many objects but can get very crowded when
the field of view is large, especially on the Series 3 version. The
`Details' dialog, <D> allows you to chose which objects and what
level of detail you want to on the chart.

   Number of stars - controls the number of stars to be plotted.
     Stars are plotted in order of magnitude, starting with the
     brightest.

   Messier objects - controls the plotting of galaxies, clusters and
     nebulae.

   Constellation lines - this item controls lines that denote the
     positions of the constellations: `outline' shows the
     traditional shapes; and `boundary' segments the sky into the
     internationally recognised areas.

   Grid lines - when enabled, grid lines are plotted at 2 hour
     intervals in right ascension, and 20 degrees declination.

   Equators - this option selects three key equators across the sky:
     the ecliptic, the celestial equator; and the galactic equator.

   Planets - controls the plotting of the nine planets.

The star chart can also show the position of the sun and moon in the
sky, which are controlled by the sun and moon marker options of the
main `Options' dialog, <O>. However, the markers shown represent the
positions only - they are not scaled to represent their diameter
with respect to the positions of the objects around them, and the
shape of the moon marker does not represent the moon's phase.

Note: Some of the items on this dialog will only appear on the
chart, if Solun can find the required `*.sol' files, as described in
the above file list.

--Including labels on your chart--

In addition to the objects specified in the `Details' dialog, the
star chart can be annotated by text labels read from a `labels'
file. The labels from up to three files can be displayed at once.

Labels are controlled by the `Label files' dialog, <F>. Three file
selectors allow the selection of individual `*.lab' files, and the
item at the top of the dialog selects which of the files should be
shown on the chart. This allows you to specify your three most used
sets of labels, but choose to plot only a selection on a particular
chart. The labels are displayed on a single line, and positioned
centrally over a specified coordinate.

The file list at the start of this document describes the content of
the supplied `*.lab' files, but you can easily create your own. The
files can be created and edited with the `Data' application, and
consist of three fields:

   RA (r) - right ascension, in decimal notation (not hour and
     minutes) and in the range 0.0 to 23.9

   Dec (d) - declination, in decimal notation (not degrees and
     minutes) and in the range -89.9 to 89.9

   Label (l) - the text of the label.

Examine one of the supplied files for examples. However you should
note that the label reading algorithm is not very robust and any
mistakes in the file, such as an invalid number, may cause the star
chart plotting to be aborted.

Note: Label files can also be used in specifying the coordinates for
an atlas view, as described above.

--Inserting new objects--

Solun allows additional objects to be plotted on a star chart
without redrawing the entire display. This allows a quick chart with
minimal detail to be plotted, and then more detail added in later.

To insert detail on the chart, simply use the `Details', <D>, and/or
the `Label files', <F>, dialogs to specify the additional detail and
select the `Insert' option of the `Insert/invert' menu, <I>.

Note: The insert function can also be used to complete a chart
previously aborted by the user.

--Inverting the display--

The star chart normally draws with black symbols on a light
background. However, if you prefer you can invert the display to
show white on black after the chart is drawn. To do this, select the
`Insert/invert' item, <I>, from the main menu and select `Invert'
from the submenu. Pressing the <I> key a second time will revert the
screen to normal display, as will redrawing the chart.

==The Almanac Functions==

The almanac panels, accessed from the `Info' menu, display
approximate information about some of the objects in the sky. This
information is calculated for the time and location currently shown
on the time display bar, at the bottom of the screen.

Note: Approximate rise/set times are shown for the object as
observed at the current location, for the 24 hour period described
by the current date and time zone, and are ordered chronologically,
with up and down arrows indicating `rise' and `set'.

Hint: To display information for a different time without waiting
for the main display to update, use the null display option, <0>.

--The sun, moon and planets--

The sun, <S>, moon, <M>, and planets, <P>, panels display
information that should be fairly self-explanatory. However a few
points should be noted:

   o the moon phase is given as the approximate percentage of the
     total area illuminated;

   o distances are shown in astronomical units (AU);

   o for the planets, distances are shown from the sun and from the
     earth respectively, on the same line;

   o the units for the rotation and sidereal periods are denoted by:
     h-hours, d-days, y-years;

   o sidereal and rotation periods are shown on a single line for
     the planets, in that order;

   o and, a negative value for the rotation period indicates
     retrograde rotation.

When using the planet information panel, select the planet you are
interested in, and press <Enter>. If you then change the selection
item to view another planet you must press <Enter> again, to update
the information.

--Lunar month and rise/set reports--

These panels show information for a number of days, rather than just
for the time currently shown on the time display bar.

   Lunar month, <B> - shows the approximate dates and times of the
     next four quarter phases of the moon, starting from the time
     shown on the time display bar.

   Rise/set report, <R> - shows the rise and set times for both the
     sun and moon, for a seven day period starting from the date
     shown on the time display bar. The times for the sun are shown
     on the left, and the moon on the right. The panel also shows
     the day on which a quarter phase of the moon falls, if any: NM-
     new moon, 1Q-first quarter, FM-full moon, 3Q-third quarter.

Note: The rise/set report can take a few minutes to calculate.

--Chart object information--

Note: This feature is only available on the registered version.

To use the `point-and-click' chart object identification feature,
select `Chart object', <Y>, from the `Info' menu, after the star
chart has been drawn. Then, using the cursor keys, move the flashing
cursor over the object you are interested in, and press <Enter>.
Solun will scan for information about the selected object.

This feature can identify the planets, sun, moon and `Messier'
objects plotted, along with the 500 brightest stars (down to about
4th magnitude). The sun, moon and planets display the relevant
almanac panels described above, but the latter two display a panel
containing information from the `*.str' files, along with the
objects position and rise/set times:

   Name - the objects given name, or a brief description, where one
     is available.

   Designation - the abbreviated name of the constellation
     containing the object and the object identifier within the
     constellation: a-alpha, b-beta, g-gamma, d-delta, e-epsilon, z-
     zeta, h-eta, @-theta, i-iota, k-kappa, l-lambda, m-mu, n-nu, E-
     xi, o-omicron, p-pi, r-rho, s-sigma, t-tau, u-upsilon, 0-phi,
     x-chi, %-psi, w-omega; or, a number.

   Type - the type of object, and it's spectral type if applicable.

Warning: There is currently a slight problem with object
identification which results in the incorrect identification of
stars that have been added to the chart by the `Insert' option.

==A Brief History==

My first astronomical program was a `planetarium' application for
the Atari ST, which I wrote out of frustration with a simple star
atlas application (and it's inability to display circumpolar views)
and in an attempt to learn the `C' programming language. Solun was
born in the summer of '93, soon after my acquiring a Series 3, and
displayed a simple day/night map ... it has been steadily growing
ever since.

   Version 1 - a simple day/night map with moon phase display, for
     the Series 3.

   Version 2 - star chart, planetarium and orrery displays added,
     along with almanac information panels and rise/set
     calculations; first public release; a second release included a
     number of improvements, including use of the `World' database
     for selection of the observer's location.

   Version 3 - weekly rise/set and lunar month displays added;
     improvements in accuracy, world map (more detailed coastline)
     and orrery displays; limited animation support; improved
     rise/set calculation; specification of atlas views by naming
     constellations; restructuring of the user-interface and
     internal design; optional sound when chart is complete; and, a
     number of more minor enhancements and bug fixes.

     The registered version also includes: high resolution Series 3a
     graphics; `point-and-click' identification of objects on the
     star chart; and a new globe view.

==Registration==

The unregistered, free distribution of this package may be used
(according to the conditions set out at the start of this document)
for an indefinite period. However, if you like this software and use
it regularly you might like to consider registration.

--Benefits of registration--

If you register you will be sent a copy of the latest registered
version of Solun. This includes many additional features over the
unregistered version, including:

   o high resolution graphics (and, with luck, faster execution) on
     Series 3a machines;

   o a extra, `globe' view depicting the earth as viewed from the
     sun, moon or above the observer's location;

   o and, `point-and-click' identification of, and information on,
     objects plotted on the star chart.

In addition I may be in a position to send you future enhancements
to Solun, as they become available.

--How to register--

To register your copy of Solun please send a contribution of 15 (UK
pounds sterling) to the address below. This contribution includes
the cost of distribution media, packaging and international postage.

Alternatively, if you are ordering from within the UK, you may
register with a lower contribution of 10, provided you send a 3.5in
MSDOS-formatted floppy disk and stamped self-addressed envelope.

Whilst UK pounds are preferred, equivalent payments in other
currencies (such as US Dollars or Deutsch Marks) will be considered,
provided an additional amount is added to cover bank exchange
charges.

Please note that if you send cash, in any currency, you do so at
your own risk.

--Distribution disk format--

Registered versions can be distributed on MSDOS format 3.5in
floppies only. 720K DD format will be normally used, but 1440K HD
format can be supplied if requested.

Note: If you have an email address that can be reached from the
Internet, then please tell me when you register, and I may be able
to send you future updates electronically.

--Registration and contact address--

The address for registration, suggestions and other correspondence
is:

     David Rushall,
     `Marker's End',
     Mounts Lane,
     Newnham,
     Northants.
     NN11 3ES
     United Kingdom

Alternative I can be contacted by email at:

     dave@between.demon.co.uk

Whilst I cannot guarantee to answer your messages, or solve any
problems with this software, I will do my best. I hope you enjoy
this application and I look forward to hearing from you.

--David Rushall - September 1995--
