+++++ Stormy Weather's Astro Software +++++
The following topics are available. You may scroll up and
down or press the first letter to go to the first title starting
with that letter. <H>ome to return here.
ABOUT CAUTION DATES GENERAL HEIGHT
INPUT JULIAN DAYS LICENSE POSITION PRINTING
SCREEN STARS TIMES ZONE TIME
ABOUT: "ASTRO" is a DOS based program (will run in Windows,
and Win95 tm Microsoft) written in QB45 with minimum requirements
of 350 kb of conventional memory available and DOS 3.3, by Stormy
Weather SoftWare, 205, Main Street, Picton, Ontario, K0K 2T0, Canada or
e-mail to email@example.com See also <G>eneral.
All algorithms are based on recent resolutions of the International
Astronomical Union, use the new standard epoch J2000.0, the FK5 system,
and new orbital theory and data from the Bureau des Longitudes in Paris.
Credit is due to J. Meeus, J. Sax, J. Laskar, C. Ron and J. Vondrak,
P. Bretagnon and G. Francou, M. Chapront-Touz‚ and J. Chapront and other
authors in various Journals, etc. Jean Meeus's "Astronomical Algorithms"
published by Willmann-Bell Inc (1991) was especially appreciated, as was
the help of Doug Mink in locating the Harvard Bright Star Catalog.
CAUTION: Regarding accuracy: our in-house testing has been
thorough but only experience from mariners, astronomers and other
end-users will show difficulties that we have not found. We would
appreciate feed back. (see <G>eneral.)
DATES: For Calendar Dates, entered as YYYY.mmdd, ex: 1997.0115
= Jan 15, 1997. (See also <J>ulian Days).
Julian and Gregorian calendars are automatically taken
into account, Friday October 15th 1582 followed Thursday October
4th 1582. For historical research, please note that many countries
did not introduce the Gregorian calendar until well after 1582.
Astronomical counting of the BC era is used in the software,
rather than "historical"; years are therfore -2, -1, 0, +1 etc.,
allowing for proper computation of leap years. For example the year
of the founding of Rome, "ab urbam conditam", is for us -752 rather
than 753 BC. The software is not necessarily valid for dates prior
to the Julian calendar ( -4712, or 1st Jan 4713 BC).
GENERAL: "ASTRO" uses complex mathematical algorithms to
produce the on-screen results. These rely heavily on the data files
that are included with the software. We do not recommend attempting
to edit or modify the data files. Even with a thorough understanding
of binary structure and verification, the results would probably be
However, all suggestions as to additions or modifications will
be seriously considered for inclusion in future releases.
We can be contacted at:
* Stormy Weather SoftWare *
* 205, Main Street, Picton *
* K0K 2T0, Ontario, Canada. *
* Email: firstname.lastname@example.org *
* Web Page: www.stormy.ca/almanac *
INPUT is Keyboard only and can be either upper or lower case.
In general, <ENTER>, <ESC>, the page up/down arrows and the up/down
and left/right arrows do all the navigation.
JULIAN DAYS: Entered as JJJJJJJ.jjjj; if the decimal part is
not entered, the Calendar time will obviously revert to 12h 0m.
LICENSE: see file LICENSE.TXT for limitations and also
distribution rights. "ASTRO" is copyright Stormy Weather
SoftWare, 1996, all rights reserved. Press <L> here for the text.
POSITION: Local Latitude and Longitude must be entered for
the validity of all ephemeris data (risings, settings, Marine sight
reductions, etc). Enter as DD.MMmmm or DDD.MMmmm, Degrees, Minutes
and decimal parts of a minute; ex 17.34123 = 17ř34.123 arcminutes.
This is in line with most GPS displays. Use negatives ( - ) pre-
ceeding the digits for Latitude South and Longitude East.
HEIGHTS: (Altitude, Height of Eye) are given in meters. For
imperial measurements (FEET) the program must be run using /f as a
parameter: in DOS ASTRO104.EXE /f at the command line - in Windows,
this should be written into the batch file (ASTRO.BAT) or used as a
PRINTING: No print routines are included in this Beta release,
although <Print Screen> has not been disabled. See GENERAL for your
suggestions if print outs might be useful to you.
SCREEN: Can be forced to Black and White (normally detected
automatically) by using /b as a command line parameter or a property
(see HEIGHTS). This could be useful for some LCD screens.
STARS and PLANETS: The four outer planets are not included in
this release (1 Beta). They will shortly be made available if
enough interest is shown.
More than 3200 stars are included, referenced by common name
in the Marine selection of 58 navigational stars, and by Bayer
and/or Flamsteed names in the astronomical portions of the soft-
ware - first select the constellation, then the star.
TIMES: This is a complex subject, but the following points
should be born in mind:
++++ Rising and setting times are in LOCAL time (see Zone time).
++++ Marine data is given in GMT (or Universal Time, UT).
++++ Astronomical (non-marine) data is in Dynamical Time (DT, no dif-
ference is made in the software between Barycentric and Terrestrial,
amounting to a maximum of 0.0017 secs due to relativistic effect).
The difference between GMT and DT (DeltaT) can only be calculated
from observations, therefore the absolute accuracy of Marine data
either carried back to the BC era or far into the future, is in
extreme doubt. From 1620 AD to the present time errors are minimal.
We have used mathematical models proposed by F.R. Stephenson. The
approximate value of DeltaT can be found under "Aries and Various".
All times are to be entered in 24 hour format, with decimal point
between the hour and the minutes, and no space between the minutes and
10.30 means half past ten in the morning
14.45 means quarter to three in the afternoon
11.2345 means eleven twenty three and forty five seconds a.m.
19.5959 is one second to eight p.m.
ZONE TIME: If entered, all risings, transits, settings (and moon
phase data on the Almanac page) will be in Local time. Zones West of
Greenwich should be Negative (preceeded by - ). Ex: For Picton, ON,
Canada enter -5 (or -4 when daylight savings are in effect).