Planetarium is an application for the Palm Connected Organizer that plots star charts and offers some unique, useful features for the beginning star gazer as well as for the professional astronomer.

It calculates the position of the sun, the moon, the planets, up to 9000 stars, hundreds of deep sky objects, comets and asteroids for any time and any geographical position and draws a sky map of any section of the sky with all 88 constellations. Stargazers can use it to help them find or identify objects in a clear night-time sky.

You can calculate twilight times, moon phases, and various astronomical information like coordinates, magnitude, distance, rise and set times and much more of the planets and all the other objects in the sky.

The useful time-increment function makes the program very interactive. You can use the Palm computer's hardware buttons to advance forward or backward in time stepwise. The time intervals are carefully chosen so that you can, for example, follow the annual path of a planet among the stars, including retrograde motion and conjunctions.

You can also use Planetarium as a compass when the sun or moon is visible. Line up the sun symbol in the compass display with the sun in the sky and your Palm shows you where north is.

Planetarium can also be used with a Telescope. Just tap an object on the star map and read off its Az/Alt or RA/Dec coordinates to set on the compass rings of your telescope. It is even simpler if you have a computerized Telescope that you can connect via the serial port of the Palm.

Features
* Draws a sky map.
* Compass view for easy location of objects in the sky
* Can be used as a compass when the sun or the moon are visible.
* Connects to telescopes via the serial port.
* Comes with a location data base of 600 major cities.
* Can be used as world clock
* Observation log to take notes of your observations.
* Can be used in the northern and shouthern hemisphere.
* The whole date range of the Palm is supported (1904 to 2030)
* Accuracy: 0.1 degrees typical.

Objects
* All planets, sun and moon
* Up to 2.5 million stars (can be determined at installation)
* 88 constellations
* Deep sky objects data base expandable. (Data sets available for 110 Messier objects and 110 Caldwell objects, 280 double stars, 400 Herschel objects and over 1000 additional deep sky objects)
* Comets and asteroids (data base expandable)

Calculations
* RA/Dec, Az/Alt of any object
* Julian date and sidereal time
* Rise and set time of any object
* Twilight times
* Moon phases
* Solstices
* Jupiter's moons
* Angular size of Saturn's rings
* Phase and elongation of the planets
* Distance and magnitude of planets
* Angular size of the planets
* Graphical representation of the phase of the moon and the inner planets.
* Magnetic declination
* Meteor showers