Libris Britannia 4/science library(b).zip/science library(b)/ASTRNOMY/STARPL20.ZIP/STARPLOT.DOC

Text File | 1993-10-10 | 32KB | 881 lines

STARPLOT VERSION 2.0                    BY BERNARD CZENKUSZ



This document contains information on the STARPLOT program.

STARPLOT may be freely copied and given away.  A minimal handling
and media charge is permitted.  As many ".STR" files should be
passed with STARPLOT as possible since the program isn't much good
without them.

If you find this program useful then an eight pounds registration
fee is requested, please see the end of this document for details.



INTRODUCTION

The program is a cross between a plotting program and a star
chart. It is intended for the production of custom designed finder
charts, with symbols, text, lines and labels.

Items are plotted using Right Ascension and Declination
coordinates against a spherical projection background which can be
moved and zoomed to give a view of the celestial sphere in any
direction.

Like a plotting program, a chart, once drawn, can be saved to a file.
Thus star charts, at different levels of detail or magnitude, can
be produced, covering any area of the sky.

Star charts can be created by either loading in from previously
made star charts, or by accessing the Hubble Guide Star Catalogue
on CD disks.


SYSTEM REQUIREMENTS

STARPLOT requires EGA or VGA capability, sorry CGA wont work.

STARPLOT V2.0 needs a hard disk as it swops parts of itself to
disk (or expanded memory) to save RAM space.

The *.STR files contain star charts which can be loaded into
STARPLOT as required.  These could be held on your hard disc or
you may want to keep them on separate floppies to avoid cluttering
up your hard disk.

STARPLOT can work with a mouse, and can print charts to an EPSON
compatible printer.

If you want to use the Hubble Guide Star Catalogue, you will need
a CD-ROM and the two CD's containing the catalogue.  Astronomical
magazines usually carry advertisements for software suppliers who
can provide these.  They are NOT included as part of the
registration fee!  (Come-on, its only eight pounds!)


STARTUP

You should have, in one directory, at least the following files;

      STARPLOT.EXE  -  The main program.

      STARPLOT.CFG  -  Holds configurations, such as colour.

      STARPLOT.DOC  -  This file.

You should also have a number of starchart files such as
BRIGHT4.STR which contains all stars to magnitude 4, or ORI.STR
which contains the constellation of Orion to magnitude 6.

There may also be *.SYM files which hold alternative symbol
definitions, these can be created using STARPLOT.

You may start the program by typing either STARPLOT or
STARPLOT NAME.STR  where NAME.STR is any star chart file name,
this automatically loads in NAME.STR saving you the trouble of
going through menu options to load in the file you want.

Wherever you are in the program, try pressing the ? key to display
context sensitive help.

If you are using STARPLOT for the first time, and you have a CD-
ROM, go to the FILE-OPTIONS menu, and set the CD-ROM drive letter,
then choose Save to store that information.  From then on STARPLOT
will know which drive to go to for the Hubble GSC.

There are two modes - CHART MODE, and CONTROL MODE.



CHART MODE

The chart is displayed and a number of commands are available to
manipulate it.  These commands are listed on the left of the
screen, ? displays them more fully.

The commands include moving and zooming the chart, and adding or
deleting items.  Certain other functions such as file loading and
saving, printing, and tabular data input are available by
pressing the Esc key and entering Control Mode.



CONTROL MODE

This consists of a series of nested menus, each menu option only
needing its initial letter to be typed to activate.  If a mouse is
used, point the mouse arrow at an option and click the left mouse
key.

Pressing the Esc key (or clicking the right mouse key) returns
back through the menu's.

If you are using STARPLOT for the first time you will need to go
through the menu's to load a file.  The *.STR files in the current
directory will be displayed, load one and then repeatedly Esc back
to Chart mode to play with it.

The top menu has the Q to Quit STARPLOT option.  At any time press
? for help.



MOUSE OPERATION

Please note: There may be some systems where the mouse does not
work correctly - if you find this, then there is an option in the
program to disable the mouse and work with cursor keys only.
(Under the FILES, OPTIONS menu).

In general the left mouse key acts like the Enter key, and the
right mouse key acts like the Esc key.

Pointing the mouse arrow at a menu option, or a data input box,
and clicking the left key chooses the option, or activates the
input box so data can be typed in.

In chart mode, clicking the left mouse key changes the chart
cursor to a mouse arrow - which can be used to point to one of
the options, though it may be just as easy to type the option
letter from the keyboard.



PLOTTED ITEMS - SYMBOLS, OBJECTS, LABELS, TEXT, CURVES

The above items are summarised here, and are dealt with in greater
detail later.

A hundred different SYMBOLS are available, which you can use.

An OBJECT is an item such as a star, and consists of a symbol
plotted at a point specified by its Right Ascension and
Declination coordinates.

A LABEL is a symbol such as a Greek letter.

TEXT is a short text string.

A CURVE is a series of up to ten points, plotted by RA and DEC
coordinates, joined together by either a smooth curve, by straight
lines or by dotted lines.  As a special case; if only two points
are used they can define a circle.



SYMBOLS

If the file STARS.SYM is present, it is automatically loaded on
program startup, it contains 100 different symbols, which are used
to plot stars, or Greek letters, or any other symbol you want.  If
STARS.SYM is not present, STARPLOT generates a default set of
symbols which should normally be sufficient for all your needs.

You are given the capability to individually edit, and redefine any
of the symbols.  You may then, if you wish, save the altered set
to a file such as MYSTARS.SYM.  If you call it STARS.SYM it will
automatically be loaded on program startup.  You may also load a
*.SYM file at any time.

If you want to generate the default set, simply start STARPLOT
without a STARS.SYM file.

Please note that Symbol 0 has special significance.  It is the null
symbol, normally left as a blank.  Any star too faint for a particular
level of zoom is plotted as symbol 0.



OBJECTS

Each object such as a star is stored with the following
information:

A 31 character name field; this can store any text you want. If
the object is a planet, this field should have name and date, see
Planet File Merge later in this document.

Magnitude.

RA and DEC coordinates; used by STARPLOT to plot the stars
position from a geocentric point of view.

Five Zoom and Symbol fields; the zoom levels are arranged in
ascending order, each with an appropriate symbol.  As the user
increases the screen zoom, the star is displayed with the symbol
for that zoom level.  Thus the stars can appear to get brighter
with zoom, by changing symbol.

If the smallest zoom value is greater than 1, say 8, then for zoom
levels 1 to 7 a blank symbol is plotted (symbol 0).



LABELS

If a label, such as the Greek letter alpha, was simply plotted at
an RA/DEC point adjacent to a star, then the following difficulty
would arise.

As you zoomed in to the star, the distance between the stars
coordinates and the labels coordinate would be magnified, and the
label would seem to move away from the star, perhaps even right
off the screen!

To avoid this, the label is tagged to the star, a screen offset is
chosen, say ten pixels to the right, and then the label is
plotted.  At any magnification, the label will now always be
plotted at ten pixels to the right of the star.

Thus a label is stored with the RA/DEC coords of the tagged
object, and the offset.  Two zoom values are also stored.  If
these are 3 to 5 for example, then the label will only be
displayed between zoom values 3 to 5.  Thus labels can appear and
disappear with changing zoom.

If it is required to plot a label at a point without tagging to an
object, then temporarily make an object, put in the label, and
delete the object.



TEXT

Text is exactly the same as a label, except where a label is
taken from the symbol file, a short text string can be typed in.



CURVES

A curve consists of a set of points joined together by lines.
These lines can be straight Lines, Dotted lines, or a smooth
Curve can be drawn through the points.  Any curve can have its
type changed by simply 'Inspecting' it and changing the value in
the 'Type' field to either 'L', 'D' or 'C'.

Curves, (and text and labels) can be switched off, so none are
displayed, or they can be individually set to be only displayed
over a range of zoom values.

A curve will only appear if all the points of the curve are on
screen together.

A smooth curve of two points is no different to a straight line of
two points, therefore the program makes an exception in this case.
If only two points are plotted, and 'C' for smooth curve is
chosen, then instead of a line between the two points, a circle
is drawn, with the first point being at the centre, and the second
point being on the circumference.



CHART MODE COMMANDS


Always remember the ? key gives context sensitive help.

ADD - Having pressed 'A' to add an object, move the cursor to the
position required and press Enter.  You will be prompted for a
name and a symbol, which will then be displayed at this position.

DELETE - 'D' deletes the item nearest the cursor.

TEXT - Having pressed 'T' you will be given a further option of
inputting a text string or a label, or switching the display of
text and labels on or off.

CURVES - Pressing 'C' gives you the option of inputting a smooth
curve, a circle, a series of straight lines or dotted lines.  You
can also choose to switch off or on the display of curves.

INSPECT - Move the cursor near to an item and press I for Inspect.
A form will be presented for that item, with symbol, zoom values
etc..

If one item, such as a curve, lies on top of an object, then the
item inspected will be the curve.  To inspect the object, use the
C for Curve command, then switch off curves.  Now only objects
will be displayed, and can be inspected.

The same forms can be accessed via the menu's in control mode,
with the added feature of scrolling through each item.  This is
particularly useful if you are inputting items from tabular data,
you do not need to use the chart modes add function.

GRID - 'G' toggles on and off a grid of RA and DEC lines, their
spacing depends on the level of zoom you are currently at.

ECLIPTIC - 'E' displays an ecliptic line.

ZOOM - On pressing 'Z' you will be prompted for a zoom value of 1
to 9999.  1 corresponds to minimum magnification, 9999 is maximum.

Pressing the Page Up or Page Down keys does a zoom up or down
without the need to type in a value.

JUMP - The jump function allows you to jump the cursor onto an
object such as a star.  This is useful when zooming onto a star.

If, for example, you just put your cursor near to a star, and then
put in a large zoom value, the star may disappear off the screen
since the distance between the star and the cursor point is
magnified.  By first 'Jumping' onto the star you can be certain
that the cursor is precisely positioned on the stars coordinates.

Jump is also useful when drawing lines between stars.  You want to
be sure a line goes to a star, and not just near it.

MOVE - To move about the sky press M.  The cursor now has a
"rubber band" to the screens centre.  Every time the Enter key is
pressed (or left mouse key).  The screen is repositioned with what
was under the cursor, now being at the screen centre.

Pressing Esc ends the move operation.

HORIZONTAL/VERTICAL INVERSIONS - Pressing H flips the screen
horizontally, V vertically.

Pressing V and then H has the combined effect of turning the
screen upside down.  So this program is useful for both North and
Southern hemispheres.  When a chart is saved, the current state of
inversion is saved with it.  So if you want BRIGHT4.STR to be the
other way up, simply load it, flip it using H and V.  Then resave
it.

Only positions are flipped, text and symbols still remain the
right way up, so you don't have to stand on your head, or read
them through a mirror.


+/-  The + and - keys can be repeatedly pressed to increase or
decrease the cursors movements under arrow key or mouse control.
It is sometimes useful, when doing detailed work to have very tiny
cursor movements, just repeatedly press the - key to achieve this.



CONTROL MODE MENUS

Pressing Esc in Chart mode will give the Control Mode menu.  This
in turn gives you more options.

A File menu for loading, saving and merging .STR files.

A Symbol menu for designing your own symbols.

A Print menu for initiating a chart print.

A Data menu for inputting or editing tabular data.

Access to the Hubble Guide Star Catalogue.



HUBBLE GUIDE STAR CATALOGUE

To load data from the GSC; first in Chart mode, move and zoom the
screen to the area of the sky you are interested in, then press
Esc for the Control Mode menu, and choose 'H'.

You will be instructed to insert one of the CD's in your CD-ROM
drive, do so and then press Enter.

STARPLOT will then search through the GSC for stars within the
area of the screen display.  If you have chosen a low zoom level,
with a corresponding large area this search can take a very long
time.  With a zoom of about 100 and greater the search will be
much shorter.

The search will look for the brightest stars in the area you have
defined, STARPLOT will pick a limiting magnitude level designed to
load in approximately 1000 stars.  So for a large area you will
get 1000 stars, and then if you zoom in to a smaller area, and do
another search you will again get a 1000 stars.  This should
always therefore give you the required detail.

During the search a progress graph will be displayed, and the
number of regions to be scanned will be shown.  Regions are the
areas into which the GSC is organised. If necessary, part way
through the search you will be asked to change the CD, so the
other half of the sky can be scanned.

Once done, the data will be shown on screen and can be manipulated
and edited as normal.


TABULAR DATA

You may wish to input an object such as a comet from tabular data,
the best way to do this is to start from a blank screen, you can
always MERGE the file onto a background of stars later.

Enter control mode, and choose the DATA option.

The Data menu has a decimal mode option, if your data is in the
format of hours, minutes and seconds, choose decimal seconds,
however if your data is just in hours and minutes, then choose
decimal minutes mode.

Then choose O for Objects, and Insert an object.  As you fill in
the data boxes please note;  Enter, Tab or Down arrow will move
you forward, Up arrow or SHIFT and TAB pressed together will move
you back a field, Esc will move you directly to the "Data
Correct?" box.

At the "Data Correct?" box, a y for yes will accept the data, an n
for no will restart at the first field to allow you to change the
data, and a further Esc will abandon the operation and lose your
inputs.

If you use a mouse, pointing and clicking at any field activates
that field for input.

There are fields for object name, magnitude and coordinates, plus
five zoom and symbol fields.

The Zoom levels and associated Symbols field contains the symbol
which will be shown at each zoom level and above.  For example;

    Zoom  4     Symbol  2
          7            13
         10            52
          0             0
          0             0

When the chart is zoomed the following display for this object
will be seen;

At zooms 1 to 3 the symbol 0 is plotted which is usually the blank
symbol, ie nothing is seen, presumably the object is too faint.

At zooms 4 to 6 the symbol 2 is plotted - not the numeral 2 but
symbol number two from the symbol set - as shown on the form.

At zooms 7 to 9 symbol 13 is plotted.

At zooms 10 to 9999 symbol 52 is plotted - the values with zoom
0 being ignored.

If all the zoom and symbol values are zero, then on typing a
magnitude value, STARPLOT will put in suggested zoom levels and
symbols for you.  You may then overwrite them if you wish.

Having filled in the data for all the objects, go to the FILES
menu and the File Information option.  There are five lines of
text which will be saved with the file.  They are for your use and
should contain information such as credits and epoch of the data.
Then save the file to a suitable NAME.STR file.

The Data menu also has the "Shrink file" option.  This deletes all
off screen items.

For example; assuming you have made a finder chart, by loading
bright5.str, all stars to magnitude 5, and you have moved to the
point of interest and have there added further detail.  You will
now want to save your chart.

Saving the whole file will however also save the entire contents
of bright5.str, which is of no use to you.  Shrinking the file
will only leave the data currently shown on screen, which can then
be saved.

The shrink option will delete anything not currently shown, if
text and curves are switched off, they will be deleted.

At low levels of zoom fainter stars are plotted as symbol 0
objects and are not shown, if you do not want the shrink file
option to delete these, temporarily redefine symbol zero as a
star, so all the too faint objects are shown.

Also under the Data menu is a "Make text file" option, this is
described below.


FILES

STARPLOT can create a number of different files.

The .STR files that hold the chart information.

The .SYM files that hold sets of one hundred symbols.

The STARPLOT.CFG file that holds options such as screen colour.

TEXT files which list all the objects, their RA and Declination
coordinates and magnitudes, in a columned ASCII format which is
both human and machine readable.  This option is available under
the Data menu.  The coordinates can be listed in either decimal
minutes or decimal seconds mode depending on the format specified
in the data menu.

PLOT TEXT FILES hold a list of the items on the screen with their
screen pixel coordinates and symbol numbers, in an ascii text
format.  These are intended for anyone who wishes to write a
routine to create the chart on some other device such as a
plotter.  The option "Save plot text file" is available in the
Print menu.

.PCX files, also available in the Print menu.  This option saves
the chart image to disk in the widely used .PCX format.  The chart
can then be imported into a great many paint and desktop
publishing programs, with all the facilities for editing and
printing that they offer.

A routine has been written "SHOW.EXE" which you may also have on
disc (if you don't have it, it can be sent to you when you
register STARPLOT), this program takes a number of the plot text
files and displays them on screen sequentially, in effect making a
slide show.


LOADING A FILE

When loading a file, a list of files is displayed, through which
you can scroll, and choose one.

The files displayed are defined by a "Find" string, so if the find
string is *.str, all the files ending with the .str extension, and
in the same directory as the STARPLOT program, will be displayed.

You may type in your own find string.  For example, if STARPLOT is
in a directory called STARPLOT, and you keep your starcharts in a
subdirectory beneath STARPLOT called STRS, then a find string of
STRS\*.STR will list your starcharts.

To save you the effort of typing in the find string whenever you
run the program, you may save it to STARPLOT.CFG which is loaded
on program startup and sets all the defaults.  To save
STARPLOT.CFG go to the File menu, choose Options, and then choose
Save.

In fact four Find strings will be saved, one for loading a
starchart file, one for loading a symbol file, and one each for
the merge and planet merge functions which are described below.
This allows you to keep symbol files, starcharts, and planet files
in different subdirectories if required.

Be aware that if you receive a copy of STARPLOT from a friend, the
find strings may be set to his or her directory structure.  It
would be helpful, if passing STARPLOT on, to make sure the Find
strings are all of the simple *.STR and *.SYM type.  Simply
deleting the file STARPLOT.CFG will in any case set all these
values to defaults.

In the File Menu there are two important functions, File Merge,
and Planet File Merge, these are described below.



FILE MERGE

It is possible to merge files, up to the maximum program limits.

This is done by loading one file as usual, and then Merging
another file into the current one, effectively adding the two
files together.

If a comet or planets path is input on to a blank screen from
published tables, then MERGE can be used to merge in a file
containing the background stars.

Another use is to merge two constellation charts to produce a
larger composite chart containing both constellations.

It may take an appreciable length of time to merge two large .STR
files, since the merge function compares every object in one file
with every object in another in an attempt to avoid duplications.



PLANET FILE MERGE

Whereas FILE MERGE just adds two files together, PLANET FILE MERGE
accesses a disc file and extracts the positions of planets for a
specified day, and adds these positions to the current file.

To enable this, there must be date information for each object in
the file, this is held in the object name field, for example;

             "Saturn  10 Oct 1992"

Usually planet information for a year is held in separate files,
PLAN1992.STR, or PLAN1993.STR for instance.

The function is not restricted to planets, any object with a
date in the name field can be extracted, comets or minor planets
for example.

The detailed action of the function is as follows:

1.  Prompts the user for a required date.

2.  Prompts the user for a file name - such as PLAN1992.STR

3.  Searches through the file for objects with a date in their
name field.

4.  Sorts the objects found by name, it gathers all the Saturn's
Venus's, Mercury's etc., together.  Ten different bodies can be
handled, each with multiple entries for different dates.

5.  For each body, if the required date is present, it is added to
the current file.

6.  If there is no entry for the body at the required date, then
the function picks out three entries for that body closest in time
to the required date.  It uses these to interpolate the position
and magnitude of the body at the required date, and adds this
made-up entry to the current file.  (There must be at least three
entries available in the required year to do this).

That's it.  You end up with the planets plotted on your chart at
their correct positions for the date you specified.

If you wish your own files to work with this function, then you
must add the date to your object names.  For example if you are
creating a file containing data for Vesta through 1995 called
VEST1995.STR, for each entry you must obey the following name
format:

               "Vesta  dd mmm yyyy"

Where dd is the day of the month, mmm is a three character month
designation, such as Jan or Jul, (July is not acceptable, it must
be only three characters) and yyyy is the four digit year number.

Stick to a single spelling of Vesta otherwise the function
will think you have data for two different bodies!

The files PLAN1992.STR, PLAN1993.STR etc., could be made by typing
in planet positions from an almanac.  However there is available a
program MAKEPLAN.EXE which generates them.  This will be sent to
you if you register STARPLOT.

MAKEPLAN V1.3 can also create files of comet and minor planet
positions from their orbitel elements.  These files could be
loaded or merged to show all positions, delineating the bodies
path through the sky, or Planet File Merge could be used to pick
out the bodies position on a single day.


FILE.STR FORMAT

There are available, from various sources, ASCII files of star
catalogues.  These files are usually made up of records, each
record being a line of text with, amongst other items of info, an
objects Right Ascension and Declination coordinates.

A program has been written, COMPSTR, which on being told the
catalogues structure, can convert it to .STR format, assuming the
catalogue is well behaved, the records being of constant length,
and the coordinate fields at set byte positions.

The "Make Text File" option in the Data menu creates such a file,
so COMPSTR could be used to convert it back to .STR format.

For anyone interested in writing their own programs that
generate files which can be used with STARPLOT the format of a
.STR file is made of the C arrays and structures listed below.

If you don't program in C, then there is another routine available
"CONVERT.EXE", which converts an ascii text format, easily
produced using GWBASIC's WRITE# command, to the .STR format
described here. Both CONVERT.EXE and COMPSTR.EXE can be sent to
you if you register STARPLOT.

Please note, all RA and DEC coords are held as 'double' variables,
these are of 64 bits, (floating point to 15 digit precision) and
contain the coordinate in minutes: Thus RA of 1 hour 5 minutes and
30 seconds will be held as 65.5,  and DEC of -10 degrees 7
arcminutes and 15 seconds will be held as -607.25.


char header[32] = "STARPLOT V1.0 STR              ";

/* The header string must contain the above Null terminated */
/* string exactly, please note the V1.0 - not V2.0, this is */
/* because version 2.0 of STARPLOT did not change the file  */
/* structure in any way */

char comments[5][32];

/* comments hold the users text comments about his file */
/* Five Null terminated strings */

int objects;

/* 16 bit integer, max value 2000 */
/* contains the number of objects */
/* Note; an object is not a text,label or curve */

/* This value is followed by the following structure */
/* repeated for every object in the file, ie "objects" times */

struct {
         char objectname[32];
         float magnitude;     /* 32 bit floating point number */
         double objectra;
         double objectdec;
         int zoomsymbol[2][5];   /* zoom values, symbol values */
       }


/* Then - */

int texts;

/* 16 bit integer, max value 200 */
/* contains the number of text strings */
/* followed by the following structure repeated for every */
/* string, ie "texts" times */

struct {
         char textstring[21];
         double textra;
         double textdec;
         int textzoomon;  /* zoom value at which text turns on */
         int textzoomoff; /* and at which text turns off */
         int textx; /* Offset distance, in pixels, from textra */
         int texty; /* and textdec at which text is displayed */
       }

/* Note: the offset distance is textx pixels to the right */
/* and texty pixels below the textra,textdec point */
/* textx and texty can be negative values to indicate left */
/* and above directions as well */

/* Then - */

int labels;

/* 16 bit integer, max value 200 */
/* contains the number of labels */
/* followed by the following structure repeated for every */
/* label, ie "labels" times */

struct {
         int labnumber;  /* The label to be displayed */
         double labelra;       /* from the .sym file */
         double labeldec;
         int labelzoomon;
         int labelzoomoff;
         int labelx;   /* offset pixels again, see above */
         int labely;
       }


/* Then - */

int curves;

/* 16 bit integer, max value 100 */
/* contains the number of curves */
/* followed by the following structure repeated for every */
/* curve, ie "curves" times */

struct {
         int curvepoints;   /* number of points, max 10 */
         double curvera[10];
         double curvedec[10];
         int curvezoomon;
         int curvezoomoff;
         char curvetype; /* Either 'C','L' or 'D' */
       }

/* Even if there are only say three points in a curve */
/* the full array of ten RA & DEC points are saved, the extra */
/* values being ignored - I know it's wasteful, but its easy */


/* Then - */

int zoom;

/* 16 bit integer, between 1 and 9999 */
/* The current zoom value of the screen when the file was */
/* saved */

double centrera;
double centredec;

/* The current coordinates of the screen centre when the file */
/* was saved */

int hinv;
int vinv;

/* Two, 16 bit integers; Horizontal and Vertical Inversion */
/* flags, 0 if inversion off, 1 if on, when the file */
/* was saved */

And that's it.

I have been asked what is the status - copyright wise, of any
program that is written to produce STARPLOT files, or any chart
that is produced by STARPLOT.  As far as I am concerned, any chart
you produce using STARPLOT is yours, I make no claim whatsoever.

As for any program you may write that produces, or uses, STARPLOT
compatible files, I'd be interested in a copy please!  But
otherwise I again make no claim whatsoever, though if you
distribute your program with copies of STARPLOT, please keep this
DOC file with it, and point out that STARPLOT is shareware and
should be registered.

On the other hand, I accept no liability for any failures of
STARPLOT.  I think it's bug free, but who knows?



FUTURE DEVELOPMENTS

I really don't know, after I've completed a version I always think
- right that's it!  I've finished. -  But then something comes
along or someone makes a suggestion which is too good not to put
in.

If you find yourself making good use of STARPLOT, please help to
pay for the sheer time put into its production by sending me an
eight pounds sterling registration fee.  Put in any comments you
may feel about the program, and what use you are making of it,
I'll find that very interesting.

On registering I'll send you a disk with the latest version of
STARPLOT, a bundle of .STR files, and the programs SHOW, CONVERT,
COMPSTR and MAKEPLAN.

MAKEPLAN produces .STR files of planetary positions, and can, on
being given orbitel elements, produce files of a minor planet or
comets positions.

(What disk size do you want, 5.25 or 3.5?)

May I express my thanks to the compilers of all star catalogues.
The easy availability of the data is a real boon. Particular
thanks to the Space Telescope Science Institute for publishing the
GSC, 18,000,000 stars is just mind blowing!

Also thanks to Robert Harold, the coordinator of the Program and
Data Library of the BAA who has converted the SAO catalogue to
.STR format (available from the BAA), and who suggested the Hubble
Guide Star Catalogue as a good medium for STARPLOT to access.

Very great thanks to those saintly souls who register their
software.

I hope STARPLOT is useful to you and you enjoy using it.

                       Bernard Czenkusz
                       3 Briggs Grove
                       Wibsey
                       Bradford
                       West Yorkshire
                       England        -    Third planet from the sun.
                                           Sol system.