No astrologer’s library can be complete without the ephemeris with the latest data from NASA’s Jet Propulsion Laboratory. The American Ephemeris by ACS is the most accurate ephemeris in the world today. In addition to planetary positions for every day in the entire 20th century, it includes a wealth of data – solar and lunar eclipses, aspectarian of Jupiter though Pluto, Chiron, Synetic Vernal Point, Moon phases and more.