V isibilidad de ES trellas
VES is an interactive fortran program that allow us to plan observations of astronomical objects. It compute the visibility and positions of the stars for the date and observatory chosen.
To start just type "ves" and an interactive pgplot window will appear on your display. Although the use is very intuitive, you can get help for the action of every window clicking on it with the center mouse button.
The starting point is a plot of elevation vs U.T. with data for
sunset and sunrise. If the Moon is visible that night, it will be
shown on the plot with a number indicating its phase (iluminated
We can change X and Y axis. Sec-Z instead of elevation in Y, and Azimut instead of U.T. in X.
To plot the trace of a new star click on the Name-window with
the left mouse button and introduce its name and return. After
this the R.A.-window is active and this coordinate can be changed.
If you don't want to change it, just type return. The same
procedure will be done for declination and equinox. If you need to
change only one coordinate click on it. Now click on DRAW-window.
A list of objects can be ploted clicking with the right mouse button on the Name-window and typing the name of a file with this list. The file format must be: Name(4:14),R.A.(16:24),DEC.(26:34),Equi.(36:41). You can create such a file with the drawed stars clicking on the file.lis-window.
To get a hard-copy of the plot click on the file.ps-window. A postscript file is created with some aditional data like night length, culmination moment and visibility duration of the stars.