Astrology Q & A: What is an ephemeris?
The ephemeris is the basic astrological tool. It is literally a schedule of the planets and their movement, with various other bits of information thrown in based on the publisher’s or author’s fetishes. As you will read in Wiki, the word means daily. It is an astronomical tool; it is not specifically made for astrologers. But since there are more of us than there are astronomers, we have helped keep them alive during times when they might otherwise have disappeared entirely (notably, plenty of times before the advent of science, which would have sort of delayed the invention of astronomy).