Heliocentric Ephemeris
Create your own Sun-centred planetary position table. Select the dates and planets you need, inspect tropical longitude and optional latitude or distance columns, and export numeric degrees as CSV.
Which centre is this?
Heliocentric means each position is measured from the centre of the Sun. Earth has a position in this table. The Sun itself is the origin, so its longitude is undefined. The Moon is omitted because this compact table focuses on planets; lunar coordinates require an explicit Earth–Moon or Moon–Sun convention. For positions as seen from Earth, use the geocentric custom ephemeris.
How to read the longitudes
A tropical longitude is an angle around the ecliptic, starting at the equinox direction called 0° Aries. One sign spans 30°. For example, 34° is 4° Taurus. The result shows degrees within a sign for quick reading; its CSV uses 0–360° numeric longitude so you can sort or plot positions. Latitude is the angle north or south of the ecliptic plane. A distance in astronomical units measures how far the planet is from the centre of the Sun, not how far it is from Earth.
These are geometric heliocentric positions derived from Astronomy Engine’s Sun-centred vectors, rotated into the true ecliptic and equinox of each date. They are not the apparent, light-time corrected geocentric positions used in many horoscopes. A planet’s heliocentric longitude and its geocentric zodiac sign can differ substantially on the same day. Earth’s heliocentric longitude is roughly opposite the Sun’s geocentric longitude, subject to the different position conventions. The selected UTC time matters, particularly for Mercury and Venus.
Custom range and coordinate choices
Select up to 90 dates at one-day or seven-day intervals. The time is held constant in UTC across the table, which makes the rows comparable even when civil time zones change. Set a shorter range to watch a fast planet; choose weekly dates for a longer overview. Selecting latitude shows departure from the ecliptic. Distance is useful for seeing where a planet is along its orbit. This calculator uses the tropical ecliptic of date throughout; it does not mix a sidereal zodiac or the fixed J2000 ecliptic into the same table.
Data is displayed to two decimals in the sign table and six decimals in the numeric CSV. That presentation precision is not an accuracy guarantee. Differences from another ephemeris may reflect its underlying planetary model, UTC versus dynamical time handling, coordinate frame, or whether positions are apparent or geometric. Pluto is included as a selectable dwarf planet because the bundled engine supplies a heliocentric vector for it; it is left unchecked initially.