Glossary

Ephemeris

An ephemeris is a table of planetary positions for each day, traditionally listing where every body stood at the same hour, which is how charts were cast before computers.

The word is Greek for a diary. A daily ephemeris gives each planet's sign, degree and minute, marks retrograde motion, and usually notes the Moon's phase.

Ours are computed with Swiss Ephemeris for 00:00 Universal Time and published as static tables, one page per month.

Frequently asked

What time are the positions for?

00:00 Universal Time, the reference a printed ephemeris has always used, so a birth later in the day sits between two rows.

Why does the Moon move so much between rows?

Because it travels roughly 12 to 15 degrees a day, more than any other body in the table.

See also