(579) Sidonia
ephemeris	date	magn	radius	delta	ra	dec	elong	phase
Today	18 Sep 2025	12.9	2.947 AU	2.216 AU	03h06m	+05°16'	128.4°	15.5°
Opposition	31 Oct 2025	12.3	2.980 AU	2.001 AU	02h40m	+03°31'	168.4°	3.8°

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 Sidonia are:

            e (Eccentricity)                : 0.0763123
            a (Semimajor axis)              : 3.0119454
            i (Inclination)                 : 11.01732
            Ω (Longitude of ascending node) : 82.62131
            ω (Argument of perihelion)      : 229.06766
            M (Mean anomaly)                : 43.83391
            Epoch                           : 2025 May 05

            L (Longitude of perihelion)     : 131.16075
            B (Latitude of perihelion)      : -8.30122
            P (Orbital period in years)     : 5.23            
        

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. A more printer-friendly version of the same chart can be found below.

Ephemerides:

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2025-09-18 00:00 UT   03 06 01.9   +05 16 14     2.216    2.947  128.4   15.5   263   12.9 
2025-09-18 01:34 UT   03 06 01.4   +05 16 06     2.215    2.947  128.5   15.5   263   12.9 
2025-09-19 00:00 UT   03 05 52.9   +05 14 09     2.206    2.948  129.4   15.3   264   12.9 
2025-09-20 00:00 UT   03 05 42.4   +05 12 00     2.197    2.949  130.4   15.0   264   12.9 
2025-09-21 00:00 UT   03 05 30.5   +05 09 48     2.188    2.950  131.4   14.8   264   12.9 
2025-09-22 00:00 UT   03 05 17.2   +05 07 33     2.179    2.950  132.4   14.6   265   12.9 
2025-09-23 00:00 UT   03 05 02.4   +05 05 15     2.170    2.951  133.4   14.3   265   12.9 
2025-09-24 00:00 UT   03 04 46.2   +05 02 54     2.161    2.952  134.4   14.1   266   12.8 
2025-09-25 00:00 UT   03 04 28.5   +05 00 30     2.153    2.953  135.4   13.8   266   12.8 
2025-09-26 00:00 UT   03 04 09.5   +04 58 04     2.145    2.953  136.4   13.5   266   12.8 
2025-09-27 00:00 UT   03 03 49.1   +04 55 35     2.137    2.954  137.5   13.3   267   12.8 
2025-09-28 00:00 UT   03 03 27.2   +04 53 05     2.129    2.955  138.5   13.0   267   12.8 
2025-09-29 00:00 UT   03 03 04.0   +04 50 32     2.121    2.956  139.5   12.7   268   12.8 
2025-09-30 00:00 UT   03 02 39.5   +04 47 58     2.114    2.956  140.6   12.4   268   12.7 
2025-10-01 00:00 UT   03 02 13.6   +04 45 22     2.106    2.957  141.6   12.1   269   12.7 
2025-10-02 00:00 UT   03 01 46.3   +04 42 45     2.099    2.958  142.6   11.9   270   12.7 
2025-10-03 00:00 UT   03 01 17.8   +04 40 07     2.092    2.959  143.7   11.6   270   12.7 
2025-10-04 00:00 UT   03 00 48.0   +04 37 27     2.086    2.959  144.7   11.3   271   12.7 
2025-10-05 00:00 UT   03 00 16.9   +04 34 47     2.079    2.960  145.8   11.0   271   12.7 
2025-10-06 00:00 UT   02 59 44.6   +04 32 06     2.073    2.961  146.8   10.7   272   12.6 
2025-10-07 00:00 UT   02 59 11.1   +04 29 25     2.067    2.962  147.9   10.3   273   12.6 
2025-10-08 00:00 UT   02 58 36.3   +04 26 44     2.061    2.962  148.9   10.0   274   12.6 
2025-10-09 00:00 UT   02 58 00.4   +04 24 02     2.056    2.963  150.0    9.7   275   12.6 
2025-10-10 00:00 UT   02 57 23.4   +04 21 21     2.051    2.964  151.0    9.4   276   12.6 
2025-10-11 00:00 UT   02 56 45.3   +04 18 40     2.045    2.965  152.0    9.1   277   12.5 
2025-10-12 00:00 UT   02 56 06.0   +04 15 59     2.041    2.965  153.1    8.8   278   12.5 
2025-10-13 00:00 UT   02 55 25.8   +04 13 19     2.036    2.966  154.1    8.4   279   12.5 
2025-10-14 00:00 UT   02 54 44.5   +04 10 41     2.032    2.967  155.1    8.1   280   12.5 
2025-10-15 00:00 UT   02 54 02.2   +04 08 03     2.028    2.968  156.2    7.8   281   12.5 
2025-10-16 00:00 UT   02 53 19.0   +04 05 28     2.024    2.968  157.2    7.5   283   12.5 
2025-10-17 00:00 UT   02 52 34.9   +04 02 54     2.021    2.969  158.2    7.2   285   12.4 
2025-10-18 00:00 UT   02 51 49.9   +04 00 22     2.017    2.970  159.2    6.9   286   12.4 

    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.