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The MICA Sky Map window has two major parts. The Sky Map itself is displayed on the left side of the window. The date, time, time scale (UT1 or TT) or time zone, and observer's latitude and longitude are displayed in the upper right corner of the Sky Map display. A key or legend identifying the plotted Solar System objects and their altitude and azimuth's are shown on the right side of the screen. The Sky Map is a polar diagram centered on the observer's zenith at the specified date and time. The outer horizon circle is at a zenith distance of 90°. The azimuth directions for North (0°), East (90°), South (180°), and West (270°) are noted just outside of the horizon circle.

The topocentric positions (refraction NOT included) of all selected objects that are above the horizon at the specified date and time are plotted in the Sky Map on the left. The Sun and Moon are always included if they are above the horizon. The user may select which other objects to include in the plot (major planets, asteroids, and/or stars. The Sun is indicated by an open circle with a 'dot' in the center. The Moon is indicated by an filled circle (regardless of phase). Planets are designated by initial letters: M=Mercury, V=Venus, A=Mars (A stands for Aries. M was already taken by Mercury), J=Jupiter, S=Saturn, N=Neptune, U=Uranus, and P=Pluto. The Asteroids are plotted with open diamond symbols.

The star symbol size and shape is correlated with brightness: an eleven pixel wide asterisk is used for stars that are brighter than 0.5 magnitude. For stars brighter than magnitude 1.5, we use a nine pixel wide asterisk. For stars brighter than magnitude 2.5, we use a seven pixel wide asterisk. 3.5 magnitude stars get a five pixel wide asterisk. A plus sign is used for stars brighter than 4.5 magnitude. Finally, a one pixel dot is used for stars fainter than magnitude 4.5. The star data comes from the external catalog of Bright Stars catalog.

The sky map plots all selected objects whose centers have a zenith distance of less than or equal to 90 degrees. This is different from the Rise/Set/Transit task which tabulates the times when the upper limbs of objects cross the horizon. In addition, the effects of refraction are not included in the sky map. This will have a negligible effect on the sky map (due to the map's scale) except for objects that are at or just below the theoretical horizon. For example, the Sun will not appear on a sky map which was generated for the time of sunrise, as predicted by MICA's Rise/Set/Transit. Instead, the Sun will appear on a sky map generated for a slightly later time.


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