(106) Dione
ephemeris	date	magn	radius	delta	ra	dec	elong	phase
Today	29 Oct 2025	13.9	3.210 AU	3.583 AU	18h25m	-26°25'	60.4°	15.6°
Opposition	18 Sep 2026	11.5	2.757 AU	1.756 AU	23h56m	-07°32'	173.3°	2.4°

The interactive orbit chart above shows the body's path through the solar system and its position at the given date. Green and blue lines are shown perpendicular to the ecliptic plane: Green if the path is above the ecliptic plane, blue if it is below. (Left-click and drag to rotate the view; Right-click and drag to move the view; Use scroll wheel to zoom in our out.)

The orbital elements of Dione are:

            e (Eccentricity)                : 0.1588532
            a (Semimajor axis)              : 3.1824910
            i (Inclination)                 : 4.57500
            Ω (Longitude of ascending node) : 61.98311
            ω (Argument of perihelion)      : 331.74654
            M (Mean anomaly)                : 279.92762
            Epoch                           : 2025 Nov 21

            L (Longitude of perihelion)     : 33.80583
            B (Latitude of perihelion)      : -2.16389
            P (Orbital period in years)     : 5.68            
        

The light curve chart below shows the estimated development of the minor planet's magnitude.

The all-sky chart below shows the path of the minor planet over the same period as the light curve. The current position is marked yellow.

The following chart shows the path of the minor planet in the next few days. The field of view is optimized for (~10x50) binoculars and finderscopes.

Ephemerides:

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2025-10-29 00:00 UT   18 25 45.6   -26 25 29     3.583    3.210   60.4   15.6    89   13.9 
2025-10-29 05:08 UT   18 26 01.6   -26 25 17     3.586    3.210   60.2   15.6    89   13.9 
2025-10-30 00:00 UT   18 27 00.6   -26 24 32     3.594    3.209   59.6   15.5    89   13.9 
2025-10-31 00:00 UT   18 28 16.3   -26 23 32     3.605    3.207   58.9   15.4    89   13.9 
2025-11-01 00:00 UT   18 29 32.5   -26 22 30     3.616    3.206   58.2   15.3    89   13.9 
2025-11-02 00:00 UT   18 30 49.4   -26 21 26     3.626    3.204   57.5   15.1    89   13.9 
2025-11-03 00:00 UT   18 32 06.7   -26 20 19     3.637    3.203   56.8   15.0    89   13.9 
2025-11-04 00:00 UT   18 33 24.7   -26 19 09     3.647    3.201   56.1   14.9    89   13.9 
2025-11-05 00:00 UT   18 34 43.1   -26 17 57     3.657    3.200   55.4   14.8    89   13.9 
2025-11-06 00:00 UT   18 36 02.1   -26 16 43     3.667    3.198   54.7   14.6    89   13.9 
2025-11-07 00:00 UT   18 37 21.7   -26 15 25     3.678    3.197   54.0   14.5    89   13.9 
2025-11-08 00:00 UT   18 38 41.7   -26 14 06     3.687    3.195   53.3   14.4    88   13.9 
2025-11-09 00:00 UT   18 40 02.3   -26 12 43     3.697    3.194   52.6   14.3    88   13.9 
2025-11-10 00:00 UT   18 41 23.3   -26 11 18     3.707    3.192   51.9   14.1    88   13.9 
2025-11-11 00:00 UT   18 42 44.9   -26 09 50     3.717    3.191   51.2   14.0    88   13.9 
2025-11-12 00:00 UT   18 44 06.9   -26 08 19     3.726    3.189   50.5   13.9    88   13.9 
2025-11-13 00:00 UT   18 45 29.5   -26 06 45     3.736    3.187   49.8   13.7    88   13.9 
2025-11-14 00:00 UT   18 46 52.4   -26 05 09     3.745    3.186   49.1   13.6    88   13.9 
2025-11-15 00:00 UT   18 48 15.9   -26 03 29     3.754    3.184   48.4   13.4    88   13.9 
2025-11-16 00:00 UT   18 49 39.8   -26 01 47     3.763    3.183   47.7   13.3    88   13.9 
2025-11-17 00:00 UT   18 51 04.1   -26 00 01     3.772    3.181   47.0   13.1    88   13.9 
2025-11-18 00:00 UT   18 52 28.9   -25 58 13     3.781    3.180   46.3   13.0    88   13.9 
2025-11-19 00:00 UT   18 53 54.1   -25 56 21     3.790    3.178   45.6   12.8    88   13.9 
2025-11-20 00:00 UT   18 55 19.7   -25 54 26     3.798    3.177   45.0   12.7    88   13.9 
2025-11-21 00:00 UT   18 56 45.8   -25 52 29     3.807    3.175   44.3   12.5    88   13.9 
2025-11-22 00:00 UT   18 58 12.2   -25 50 28     3.815    3.174   43.6   12.4    87   13.9 
2025-11-23 00:00 UT   18 59 39.0   -25 48 24     3.823    3.172   42.9   12.2    87   13.9 
2025-11-24 00:00 UT   19 01 06.2   -25 46 16     3.831    3.171   42.2   12.1    87   13.9 
2025-11-25 00:00 UT   19 02 33.8   -25 44 06     3.839    3.169   41.6   11.9    87   13.9 

    Terminology:
            
    delta:  distance between minor planet and earth in AU
    radius: distance between minor planet and sun in AU
    magn:   magnitude (brightness) estimate    
    ra:     right ascension in hours (24h = 360deg)
    dec:    declination in degrees
    elong:  elongation in degrees (angle sun-earth-minor planet)    
    phase:  phase angle in degrees (angle sun-minor planet-earth)        
    AU:     Astronomical Unit (mean distance between earth and sun: 149597870.7 km
    

Orbital elements provided by the MPC (Minor Planet Center).
Calculations by a modified version of AAPlus, a C# implementation of the AA+ project by PJ Naughter from the algorithms presented in the book "Astronomical Algorithms" by Jean Meeus.
NGC2000 dso catalog and star labels from VizieR as provided by the Strasbourg astronomical Data Center.
Tycho2 catalog from the ESO archive.