Planetary, Lunar, and Stellar Visibility (successor to Planet's Visibility 2.0) presents a 3-color diagram that shows when a planet, a star, the moon or the sun is visible during any year from 3000 BC to AD 6000 at any location on the earth. The vertical axis marks the months of the year, the horizontal axis marks the hours of the day. The three colors create a contour map effect and show whether the body is under the horizon (black) and invisible, above the horizon with the sun (light color) and invisible, above the horizon without the sun (shaded color) and so possibly visible. The times of sunrise and sunset and when the sun reaches specified altitudes above or below the horizon can be shown as curves on the diagrams. By moving the mouse over the diagram, the date and time along with the object's altitude, azimuth, and magnitude, or the phase of the moon, are displayed. In addition, Planetary, Lunar, and Stellar Visibility computes and tabulates the dates of visibility phenomena: for planets and stars first and last visibility, acronychal rising and cosmical setting; for the moon first and last visibility, and the tables provide much supplementary information. These phenomena are very useful for historical purposes. Since the computation of visibility phenomena is complex and uncertain, alternate methods are provided and parameters can be altered by the user to find what appear to be the best results. There are also diagrams of solar and lunar eclipses, of the rotation, inclination, illumination, and apparent size of the bodies, and of Jupiter's satellites. The settings for the computations may be saved, the graphics may be saved, pasted into documents, and printed, and the tables for visibility phenomena may be accumulated, edited, printed, and saved as .rtf files or HTML files to be pasted into documents and printed.
Full Documentation is provided.
Planetary, Lunar, and Stellar Visibility is freeware and runs under Windows 98, ME, 2000 and XP.
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Version 3.1 has the more stable database engine and a few other fixes.
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 dates of the heliacal phenomena of the planets and stars:
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The heliacal/acronychal dates window shows the dates of visibility phenomena, the times of planet rise/set and sun rise/set associated with the visibility, the interval of time (d r/s) in the form d r/s = planet r/s – sun r/s, the “age” of the phenomenon, the interval in days and hours of planet r/s of first and last visibility from true conjunction and of acronychal rising and cosmical setting from true opposition, and the magnitude of the planet.
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The more information window then gives additional information, all to minutes of arc, for the time of planet rise/set: (negative) altitude and longitude of the sun, longitude, latitude, and magnitude of the planet, difference of azimuth and of longitude of the planet and sun. The same information is given for visibility phenomena of stars. In either window, click on text/print; an edit text window opens containing the information, which can be edited, saved as an .rtf file, printed, and pasted into other documents.
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 dates of the first and last visibility of the moon:
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The window first and last visibility of the moon shows the phenomenon, first visibility or last visibility, the date, the times of sun rise/set and moon rise/set, the interval of time (d r/s) in the form d r/s = moon rise/set – sun rise/set, the phase of the moon in percent illumination, the "age" of the moon at sun rise/set in hours before (–) or after (blank) true conjunction, and the length (period) of the preceding month, the interval between first visibilities, in integer days, 29 or 30.
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The more information window for the moon then gives in addition to the date and times, for the time of sun rise/set:
the longitude of the sun, the longitude, latitude, and altitude of the center of the moon, the phase of the moon, and the difference of azimuth and difference of longitude in the form moon – sun. In either window, click on text/print; an edit text window opens containing the information, which can be edited, saved as an .rtf file, printed, and pasted into other documents.
In addition to the information displayed in windows and accumulated in .rtf files, HTML files can be computed containing all information on visibility phenomena of the moon, a planet or a star for up to 100 years and of the times of rising, culmination, and setting of the sun and the moon, planet or star, with their differences, for every day of the year.
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 The solar and lunar eclipse windows:
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The information shown for a solar eclipse is: date and time in UT (to 15 seconds), delta T between UT and ephemeris time in seconds, eclipse fraction in percent, distance between centers and apparent diameters of the sun and moon (to 1"), altitude and azimuth of sun and moon (to 1'). The information shown for a lunar eclipse is: date and time in UT (to 25 seconds), delta T between UT and ephemeris time in seconds, eclipse fraction in percent, apparent diameter of the moon (to 1"), distance in kilometers, altitude and azimuth (to 1'). The time is given in UT regardless of the selected location of the observer.
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 Jupiter's satellites:
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The window Jupiter's satellites shows the paths of the four Galilean satellites. All information in this window is geocentric and in UT regardless of the selected location of the observer. The up arrow in the window reduces the number of days and the intervals of time within each day; the down arrow increases the number of days and the intervals of time within each day. Moving the cursor vertically over the satellites diagram shows, below the diagram, the movement of the satellites on either side of Jupiter, distinguishing transits in front of and occultations behind the planet, with the date and time in UT below the diagram. The least interval of time is 10 minutes, the greatest interval is 2 hours. The numbers at the bottom of the window, selected by the arrow, show the directions and distances of the satellites from Jupiter in diameters of Jupiter or in arc minutes, and the diameter of Jupiter in seconds, all to 0.01 units. For the individual satellites are shown obs(ervational) information: distance from center of Jupiter in rectangular coordinates x and y (to 0.01'), mean magnitude (to 0.01), apparent diameter (to 0.01"); orb(ital) information: major axis (km), period (days), eccentricity, inclination to Jupiter's equatorial plane; and phy(sical) information: mass (kg), radius (km), density (g/cm3), and mean temperature (C).
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 Rotation/illumination diagrams for the planets, the moon and the sun:
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The rotation/illumination window for the planets shows the geocentric rotation, inclination, illumination, and variation of apparent size of the object. All information in this window is geocentric and in UT regardless of the selected location of the observer. The N(orth) – S(outh) directions are to the celestial poles, the E(ast) – W(est) directions are parallel to the celestial equator.
The information given in the window is (left column): date, time (UT to 0:04h), geocentric right ascension (to 0:01h) and declination (to 1'), elongation from the sun (to 0.1°), apparent diameter (to 0.1"), magnitude (to 0.1); (right column): position angle between the northern extremity of the axis of rotation and celestial pole measured from north through east (to 0.1°), phase angle, that is, the elongation of the earth from the sun measured at the center of the planet, the phase in percent illumination, and the planetocentric position of the earth: latitude north (+) and south (-) of the planet's equator, longitude to the east along the planet's equator with respect to the defined prime meridian of the planet.
These diagrams are provided for all the planets; the examples here are Mercury, Mars, and Jupiter.
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For Jupiter longitude is shown for systems I (equator), II (containing great red spot), and III (radio emissions and magnetic field); for Saturn longitude is shown for systems I (equator) and III (radio emissions and magnetic field). These differential rotations are also distinguished in the diagrams by arcs of meridians.
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For the moon, the position angle of the axis of rotation and position angle of the midpoint of the bright limb measured from north through east, the colongitude, that is, the selenographic longitude of the morning terminator, phase angle (180° - elongation), phase in percent illumination, the selenographic position of the earth, which shows the librations of the central point of the lunar disc: in latitude to the north (+) and south (-), in longitude to east (+) and west (-).
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For the sun, the position angle of the axis of rotation measured from north through east, the heliocentric position of the earth: latitude north (+) and south (-) of the solar equator, longitude to the east along the solar equator measured from the solar prime meridian.
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user may add any number of locations
and variation of apparent magnitude by shadings, from light when the planet is brighter to dark when fainter (if the computer’s color resolution is 15 bpp. or better, meaning “high color” or “true color”) 
