(230) Athamantis
ephemeris	date	magn	radius	delta	ra	dec	elong	phase
Today	18 Sep 2025	11.9	2.340 AU	1.914 AU	18h28m	-12°58'	102.0°	24.8°
Opposition	5 Dec 2026	10.1	2.293 AU	1.309 AU	04h52m	+18°31'	175.9°	1.8°

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 Athamantis are:

            e (Eccentricity)                : 0.0611874
            a (Semimajor axis)              : 2.3825833
            i (Inclination)                 : 9.45497
            Ω (Longitude of ascending node) : 239.77081
            ω (Argument of perihelion)      : 139.09056
            M (Mean anomaly)                : 254.03342
            Epoch                           : 2025 May 05

            L (Longitude of perihelion)     : 199.24884
            B (Latitude of perihelion)      : 6.17562
            P (Orbital period in years)     : 3.68            
        

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. 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   18 28 58.5   -12 58 11     1.914    2.340  102.0   24.8    89   11.9 
2025-09-18 03:48 UT   18 29 06.2   -12 58 27     1.916    2.340  101.9   24.9    89   11.9 
2025-09-19 00:00 UT   18 29 47.8   -12 59 52     1.926    2.339  101.2   24.9    89   11.9 
2025-09-20 00:00 UT   18 30 38.5   -13 01 30     1.937    2.338  100.5   25.0    89   11.9 
2025-09-21 00:00 UT   18 31 30.6   -13 03 05     1.948    2.338   99.7   25.0    89   11.9 
2025-09-22 00:00 UT   18 32 24.0   -13 04 39     1.960    2.337   99.0   25.1    88   12.0 
2025-09-23 00:00 UT   18 33 18.7   -13 06 09     1.971    2.336   98.2   25.2    88   12.0 
2025-09-24 00:00 UT   18 34 14.7   -13 07 37     1.982    2.336   97.5   25.2    88   12.0 
2025-09-25 00:00 UT   18 35 12.0   -13 09 02     1.994    2.335   96.8   25.2    88   12.0 
2025-09-26 00:00 UT   18 36 10.6   -13 10 25     2.005    2.334   96.0   25.3    87   12.0 
2025-09-27 00:00 UT   18 37 10.4   -13 11 44     2.017    2.334   95.3   25.3    87   12.0 
2025-09-28 00:00 UT   18 38 11.4   -13 12 60     2.028    2.333   94.6   25.4    87   12.0 
2025-09-29 00:00 UT   18 39 13.6   -13 14 13     2.040    2.332   93.9   25.4    87   12.1 
2025-09-30 00:00 UT   18 40 17.0   -13 15 22     2.051    2.332   93.2   25.4    87   12.1 
2025-10-01 00:00 UT   18 41 21.6   -13 16 28     2.063    2.331   92.5   25.4    86   12.1 
2025-10-02 00:00 UT   18 42 27.2   -13 17 30     2.074    2.330   91.7   25.4    86   12.1 
2025-10-03 00:00 UT   18 43 34.0   -13 18 29     2.086    2.330   91.0   25.4    86   12.1 
2025-10-04 00:00 UT   18 44 41.9   -13 19 24     2.097    2.329   90.4   25.4    86   12.1 
2025-10-05 00:00 UT   18 45 50.9   -13 20 15     2.109    2.328   89.7   25.4    85   12.1 
2025-10-06 00:00 UT   18 47 00.9   -13 21 02     2.120    2.328   89.0   25.4    85   12.1 
2025-10-07 00:00 UT   18 48 12.0   -13 21 46     2.132    2.327   88.3   25.4    85   12.1 
2025-10-08 00:00 UT   18 49 24.1   -13 22 25     2.143    2.327   87.6   25.4    85   12.2 
2025-10-09 00:00 UT   18 50 37.2   -13 23 00     2.155    2.326   86.9   25.4    84   12.2 
2025-10-10 00:00 UT   18 51 51.3   -13 23 31     2.166    2.325   86.2   25.4    84   12.2 
2025-10-11 00:00 UT   18 53 06.4   -13 23 58     2.178    2.325   85.6   25.4    84   12.2 
2025-10-12 00:00 UT   18 54 22.4   -13 24 20     2.189    2.324   84.9   25.3    84   12.2 
2025-10-13 00:00 UT   18 55 39.3   -13 24 38     2.201    2.323   84.2   25.3    83   12.2 
2025-10-14 00:00 UT   18 56 57.2   -13 24 52     2.212    2.323   83.6   25.3    83   12.2 
2025-10-15 00:00 UT   18 58 16.1   -13 25 01     2.224    2.322   82.9   25.2    83   12.2 
2025-10-16 00:00 UT   18 59 35.8   -13 25 05     2.235    2.321   82.3   25.2    83   12.2 
2025-10-17 00:00 UT   19 00 56.4   -13 25 05     2.247    2.321   81.6   25.1    83   12.2 
2025-10-18 00:00 UT   19 02 17.9   -13 24 59     2.258    2.320   80.9   25.1    82   12.3 

    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.