(121) Hermione
ephemeris	date	magn	radius	delta	ra	dec	elong	phase
Today	16 Sep 2025	14.2	3.815 AU	4.557 AU	13h59m	-08°33'	38.0°	9.3°
Opposition	5 Jun 2026	12.3	3.595 AU	2.580 AU	16h52m	-22°51'	179.7°	0.1°

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 Hermione are:

            e (Eccentricity)                : 0.1248676
            a (Semimajor axis)              : 3.4562492
            i (Inclination)                 : 7.56664
            Ω (Longitude of ascending node) : 72.87341
            ω (Argument of perihelion)      : 297.05553
            M (Mean anomaly)                : 197.26865
            Epoch                           : 2025 May 05

            L (Longitude of perihelion)     : 10.13244
            B (Latitude of perihelion)      : -6.73452
            P (Orbital period in years)     : 6.43            
        

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
2025-09-16 00:00 UT   13 59 47.7   -08 33 18     4.557    3.815   38.0    9.3   106   14.2 
2025-09-16 00:03 UT   13 59 47.8   -08 33 18     4.557    3.815   38.0    9.3   106   14.2 
2025-09-17 00:00 UT   14 00 48.6   -08 39 60     4.565    3.814   37.3    9.2   106   14.2 
2025-09-18 00:00 UT   14 01 49.8   -08 46 42     4.573    3.814   36.6    9.0   105   14.2 
2025-09-19 00:00 UT   14 02 51.4   -08 53 24     4.581    3.813   35.9    8.9   105   14.2 
2025-09-20 00:00 UT   14 03 53.3   -09 00 07     4.589    3.812   35.2    8.7   105   14.2 
2025-09-21 00:00 UT   14 04 55.5   -09 06 49     4.597    3.812   34.5    8.6   105   14.2 
2025-09-22 00:00 UT   14 05 58.0   -09 13 31     4.605    3.811   33.8    8.4   105   14.2 
2025-09-23 00:00 UT   14 07 00.9   -09 20 13     4.612    3.811   33.1    8.3   105   14.2 
2025-09-24 00:00 UT   14 08 04.0   -09 26 55     4.619    3.810   32.4    8.1   105   14.2 
2025-09-25 00:00 UT   14 09 07.4   -09 33 37     4.626    3.809   31.7    8.0   104   14.2 
2025-09-26 00:00 UT   14 10 11.1   -09 40 18     4.633    3.809   31.0    7.8   104   14.2 
2025-09-27 00:00 UT   14 11 15.1   -09 46 59     4.640    3.808   30.3    7.6   104   14.2 
2025-09-28 00:00 UT   14 12 19.4   -09 53 40     4.646    3.808   29.6    7.5   104   14.2 
2025-09-29 00:00 UT   14 13 24.0   -10 00 20     4.653    3.807   28.9    7.3   104   14.2 
2025-09-30 00:00 UT   14 14 28.8   -10 06 60     4.659    3.806   28.2    7.2   103   14.2 
2025-10-01 00:00 UT   14 15 33.9   -10 13 39     4.665    3.806   27.5    7.0   103   14.2 
2025-10-02 00:00 UT   14 16 39.3   -10 20 18     4.671    3.805   26.9    6.8   103   14.2 
2025-10-03 00:00 UT   14 17 44.9   -10 26 57     4.677    3.804   26.2    6.7   103   14.2 
2025-10-04 00:00 UT   14 18 50.8   -10 33 34     4.683    3.804   25.5    6.5   103   14.1 
2025-10-05 00:00 UT   14 19 57.0   -10 40 12     4.688    3.803   24.8    6.3   102   14.1 
2025-10-06 00:00 UT   14 21 03.4   -10 46 48     4.693    3.803   24.1    6.2   102   14.1 
2025-10-07 00:00 UT   14 22 10.0   -10 53 24     4.698    3.802   23.4    6.0   102   14.1 
2025-10-08 00:00 UT   14 23 16.9   -10 59 59     4.703    3.801   22.7    5.8   102   14.1 
2025-10-09 00:00 UT   14 24 24.0   -11 06 33     4.708    3.801   22.0    5.7   101   14.1 
2025-10-10 00:00 UT   14 25 31.3   -11 13 07     4.713    3.800   21.4    5.5   101   14.1 
2025-10-11 00:00 UT   14 26 38.9   -11 19 39     4.717    3.799   20.7    5.3   101   14.1 
2025-10-12 00:00 UT   14 27 46.7   -11 26 11     4.722    3.799   20.0    5.2   100   14.1 
2025-10-13 00:00 UT   14 28 54.7   -11 32 42     4.726    3.798   19.3    5.0   100   14.1 
2025-10-14 00:00 UT   14 30 03.0   -11 39 13     4.730    3.798   18.6    4.8   100   14.1 
2025-10-15 00:00 UT   14 31 11.5   -11 45 42     4.733    3.797   17.9    4.6    99   14.1 

    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.