Alcyone Ephemeris 3.4 is an accurate and fast astronomical ephemeris calculator covering the period 3000 BC to AD 3000. It calculates heliocentric, geocentric, and topocentric positions of the Sun (Earth), Moon, planets, minor planets, comets and fixed stars in ecliptical, equatorial, and horizontal coordinates (including angular differences between two bodies), with optional corrections for parallax and refraction; rectangular coordinates, velocity, apparent diameter, magnitude, phase, lunar libration, orbital elements, differences for all of these, and more (see List of available ephemeris data).

download free trial (~46 MB)

In addition Alcyone Ephemeris offers a wealth of functionality: star chart generation, 3D-visualization of heliocentric and planetocentric orbits, plotting ephemeris data (as a function of time or in a parametric plot), searching for specific values, data export (HTML, Excel, Text, CSV, XML), printing, and (PDF-/HTML-/RTF-) report generation (see Functions, Screenshots). Access to the complete Bright Star Catalogue, calendar conversion, and an astronomical event calculator are available.
The ephemeris calculation is based upon Steve Moshier's analytical ephemeris using trigonometric expansions for the earth and planets and the lunar ephemeris ELP2000-85 of Chapront-Touzé and Chapront for the moon, both adjusted to Jet Propulsion Laboratory's DE404 (see www.moshier.net). There are further adjustments in Alcyone Ephemeris, some optional, to JPL's more recent DE406, the most accurate long-term ephemeris. Alcyone Ephemeris is fast. With an Athlon XP 2000+ processor, 100 calculations of geocentric longitude, latitude, and distance for the sun, moon, and all planets take about 2 seconds.
A comprehensive documentation includes tabular and graphic comparisons of calculations with HORIZONS ephemeris generator. Alcyone Ephemeris runs under Windows 98/ME/2000/XP/Vista.

download Alcyone Ephemeris (~46 MByte)

1. ecliptical coordinates, spherical (longitude, latitude, distance) and rectangular
2. equatorial coordinates, spherical (right ascension, declination, distance) and rectangular
3. velocities (rectangular and orbital)
4. angular separation between two celestial bodies

5. ecliptical coordinates, spherical (longitude, latitude, distance) and rectangular
6. equatorial coordinates, spherical (right ascension, declination, distance) and rectangular
7. elongation and mean elongation
8. magnitude, phase, apparent diameter
9. angular separation between two celestial bodies

10. topocentric ecliptical coordinates (longitude and latitude)
11. topocentric equatorial coordinates (right ascension and declination)
12. topocentric horizontal coordinates (azimuth and altitude)
13. angular separation between two celestial bodies

14. mean orbital elements (semimajor axis, eccentricity, mean longitude, longitude of perihelion, longitude of ascending node, inclination
15. osculating lunar orbital elements

16. optical and physical lunar libration in longitude and latitude
17. position angle of the moon's axis of rotation
18. selenographic longitude and latitude of the Sun
19. selenograpic colongitude of the Sun
20. position angle of the midpoint of the bright limb

Calculates heliocentric, geocentric, and topocentric positions of the Sun (Earth), Moon, planets, minor planets, comets and fixed stars in ecliptical, equatorial, and horizontal coordinates (including angular differences between two bodies), with optional corrections for parallax and refraction; rectangular coordinates, velocity, apparent diameter, magnitude, phase, lunar libration, and orbital elements, covering the period 3000 BC to AD 3000.

Ephemeris data can be visualized in star charts (see examples)

Ephemeris data can be used for generation of three-dimensional visualizations of heliocentric or planetocentric orbits (more)

Ephemeris data can be plotted as a function of time (more).

Pairs of ephemeris data can be plotted in parametric plots as a function of time (more).

The ephemeris data of a column can be searched for specific values (more).

Dates/times can be specified as ephemeris time (ET) or universal time (UT).

AE offers eight different formulas and tabular interpolation for calculation of delta T

Calculate angular separation between two celestial bodies (planets, sun, moon, stars) (more).

In the difference mode all ephemeris data are calculated as changes of the respective values over a specified time of (a) one hour, (b) one day or (c) the current selected interval of the ephemeris calculation (more).

For each date/time of the ephemeris calculation, additional information can be calculated and shown in the ephemeris table: Julian day number, mean obliquity of the ecliptic, delta T (ET-UT), general/lunisolar precession, nutation in longitude and obliquity, equation of time, apparent local time, sideral time at Greenwich, local sideral time (more).

The Date / time calculator allows the computation of the instants of
• the equinoxes and solstices
• the start of the Besselian years
• the lunar phases (new moon, first quarter, full moon, last quarter)
• planetary configurations (oppositions, conjunctions, and greatest elongations)
• passages of perihelion (perigee), aphelion (apogee), and nodes
• rises, culminations, and sets.

The values shown in the ephemeris can be formatted in different ways (more).

Ephemeris data, plots and graphics can be printed.

Reports with ephemeris data, plots and graphics can be generated as PDF-, HTML- or RTF-files.

Ephemeris data can be exported to HTML, Excel, Text, or CSV files.

The complete data from the Bright Star Catalogue can be accessed (more).

1. Close Jupiter-Saturn Conjunction in 1563 (show)
2. Double Opposition of Jupiter and Saturn in 7 B.C. (show)
3. Solar Eclipse on 2008-02-07 (show)
4. Total Lunar Eclipse on 2008-02-20 (show)
5. Moon in Pleiades on 2007-12-21 (show)
6. Mars Opposition in 2007 (show)
7. Mars-Antares Angular Separation (show)
8. Halley's Perihelion Passage in 1986 (show)
9. Opposition of Ceres in 2006 (show)
10. Occultation of Albaldah (Pi Sgr) by Venus in 2035 (show)
11. Occultation of Graffias (Beta Scorpii) by Jupiter in 1971 (show)
12. Topocentric Ephemeris (show)
13. Lunar Libration (2-parametric plot) (show)
14. Venus' Position at Sun Rise (show)
15. The Orbit of Halley's Comet 1945-2027 (show)
16. Neptune-Pluto Resonance (parametric plot) (show)
17. Geocentric Jupiter-Saturn Conjunctions 185 B.C - A.D. 2080 (show)
18. Orbit of Asteroid Apophis 2024-2035 (Orbital Period Increase) (show)

1. Occultation of Venus by the Cresent Moon (2008-12-01)) (show)
2. Moon im M44 (Praesepe), 2008-04-13 (PDF) (show)

1. geocentric ecliptical positions and distances of Mercury, Venus, and Mars at intervals of 1 day, including additional information (Julian day number) (show)
2. geocentric equatorial positions, distances, aparent magnitudes, and phases of Mars, Jupiter, and Saturn at intervals of 2 days, angles decimal formatted (show)
3. geocentric ecliptical position, magnitude, phase, apparent diameter, and elongation of Mars at intervals of 12 hours, during its opposition in 2007 (show)
4. topocentric positions of the sun and the naked-eye visible planets of one day at intervals of 30 minutes (show)
5. geocentric ecliptical positions and distances of Jupiter and Saturn at the instants of their conjunctions 185 B.C - A.D. 2080 (show)