MOONCLOCK for Mac

From sofTouch APpLications:

MOONCLOCK produces a continually updating, real-time graphical representation on the visual aspect of the moon. The lunar aspect may be computed geocentrically, or topocentrically, for the current epoch, or for any time and date.

The dynamic MOONCLOCK graphic depicts how the moon would appear to the observer. The light and dark shaded portions of the lunar graphic represent the regions of lunar day and night. The direction from the Moon's center to celestial north is also indicated. To the tight of the lunar graphic the following information is presented:

• The lunar elongation angle (measured eastward from the sun)
• The position angle of the bright limb (measured eastward from celestial North to the mid-point of the bright limb)
• The percentage of the lunar surface illuminated by sunlight
• The current (or selected) Universal Time and Date
• The geographic longitude at which the sidereal time is 0 hours
• The observer's sidereal time
• The azimuth and altitude of the moon

An instantaneous lunar ephemeris is presented in the bottom of the MOONCLOCK window. The header for the ephemeris indicates whether positional computations were performed geocentrically or topocentrically, and the epoch of the ephemeris as both Julian and Gregorian dates.

The lunar Right Ascension, Declination, Heliocentric Latitude, Heliocentric Longitude, apparent angular Equatorial Radius, and Distance from the Earth is displayed. The equatorial coordinates of the moon are precessed to the equator and equinox of 2000.0. A.D. The lunar distance is expressed in Earth radii. The lunar angular radius is expressed in seconds of arc.