
 ASTRONOMY-0    Simplified vesion of the program ASTRONOM.82g 
 ------------------------------------------------------------


It needs less memory, only one program without subroutines, 
but provides lower accuracy for dates in far future or in the past,
it is impossible to enter another object.

The program is freeware, but it isn't allowed to use it for astrological
purposes.


The program needs less than 5Kb of memory altogether. It uses the variables 
A..Z,  L4, L5. All the data required for calculations are stored in 
the program itself.



Installation:
-------------

1. Load  the file ASTRONO0.82p into your calculator.
   No subroutines included in ASTRONOM.82g are required.

2. Set your observing place.
(It isn't necessary to set, if you let the original Central European setting,
the program will work with a bit lesser accuracy everywhere around 
the 50 degrees of latitude.)

In the first three lines of the program there is:
50'00'/->/P        (latitude)
15'00'/->/G        (longitude)
-1 /->/W          (correction of used time in HH.MM to the universal time)
This is the setting for the Middle Europe, 50 degrees of north latitude,
15 degrees of east longitude, 
the correction of the zone time to the universal time is -1 hour.
Correct these lines according your geographical location and  the zone time.
For New York it is for example
        40'45' /->/ P
        -74'00' /->/ G
         5 /->/ W



Usage:
------

Run the ASTRONO0, enter Year.MonthDay and then Hours.Min. The appearance 
of the sky in given time will be drawn. The Sun, the Moon and planets are 
symbolised by signs described in Pic6 (ASTRONOM.82g). The curve represents
the horizon. South is in the middle, North at the edge of the screen. 
Each object marked by its sign corresponds to the point under the straight
line. These points help distinguish signs of planets in case they are near
each other.
There is marked 50 bright stars. You can easily recognise these  
constellations: Cyg, Uma, Leo, Ori, Cas, And, Peg. The following stars are 
drawn by a greater point: Vega, Deneb, Atair, Arcturus, Sirius and Capela.
You can use the function ZoomIn (or Zbox) for zooming of a chosen area. After
running the Zoom the horizon will be initially drawn. For redrawing 
of the objects it is necessary to run the program again and instead of 
the date give YYYY.MMDD=0. The positions of planets will not be calculated
again, they only will be redrawn. 
If you want to change only hours and not the date you can enter only 
YYYY.MMDD=1 and then the time. By that the last zoom will remain and 
no calculations will be done again, the positions of planets will be only 
shifted according to the time. 
(If the time difference is greater the accuracy of drawn positions will be 
lesser.)
You can find the coordinates of the figured objects in L4 and L5. There is 
right ascension  in hours in L4 and declination in degrees in L5. 
On the position 1 there is The Sun, 2 - The Moon, 3 - Mercury, 4 - Venus,
5 - Mars, 6 - Jupiter, 7 - Saturn and from 11 there are stars.


Accuracy:
---------

The position of stars and the Moon is given with accuracy about 1 degree. 
The stars are here only for rough orientation and better calculation of 
the position of the Moon would be too complicated (more accurate formulae 
and topocentric corrections).
The accuracy of the position of the Sun and planets comes from the solution 
of the problem of two bodies without calculating mutual gravitational forces
among the planets (about one minute of arc for a date near the year 2000).





Used formulae:
--------------

I used for calculations the adapted formulae from following books:
1. J.Meeus "Astronomical formulae for calculators." Monografieen over 
  astronomie en Astrofyzica, 4, Volkssterrenwatch Urania (Hove) 
  en Vereniging voor Sterrenkunde (Brussel) 1979  
2. (for the Moon) 
  "The Astronomical Almanac for the year 1985." Nautical Almanac Office, 
  Washington, London 1984.




------------------
by Jirka Bubenicek
   bubenic@fnkv.cz
------------------
