(17) Thetis
ephemeris	date	magn	radius	delta	ra	dec	elong	phase
Opposition	30 Dec 2025	11.6	2.778 AU	1.796 AU	06h40m	+19°15'	176.1°	1.4°
Today	5 Jan 2026	11.7	2.775 AU	1.797 AU	06h34m	+19°30'	172.8°	2.5°

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 Thetis are:

            e (Eccentricity)                : 0.1312584
            a (Semimajor axis)              : 2.4728226
            i (Inclination)                 : 5.59392
            Ω (Longitude of ascending node) : 125.50275
            ω (Argument of perihelion)      : 135.94951
            M (Mean anomaly)                : 192.66164
            Epoch                           : 2025 Nov 21

            L (Longitude of perihelion)     : 81.58893
            B (Latitude of perihelion)      : 3.88621
            P (Orbital period in years)     : 3.89            
        

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
2026-01-05 00:00 UT   06 34 22.9   +19 30 33     1.797    2.775  172.8    2.5    63   11.7 
2026-01-05 08:45 UT   06 34 00.1   +19 31 32     1.797    2.775  172.4    2.7    65   11.7 
2026-01-06 00:00 UT   06 33 20.4   +19 33 14     1.798    2.775  171.7    2.9    67   11.7 
2026-01-07 00:00 UT   06 32 18.3   +19 35 55     1.799    2.774  170.6    3.3    71   11.7 
2026-01-08 00:00 UT   06 31 16.7   +19 38 36     1.801    2.774  169.4    3.7    73   11.8 
2026-01-09 00:00 UT   06 30 15.5   +19 41 18     1.803    2.773  168.2    4.1    76   11.8 
2026-01-10 00:00 UT   06 29 14.9   +19 43 59     1.806    2.773  167.0    4.6    77   11.8 
2026-01-11 00:00 UT   06 28 15.0   +19 46 41     1.808    2.772  165.8    5.0    79   11.8 
2026-01-12 00:00 UT   06 27 15.7   +19 49 22     1.811    2.772  164.6    5.4    80   11.9 
2026-01-13 00:00 UT   06 26 17.2   +19 52 03     1.814    2.771  163.4    5.8    81   11.9 
2026-01-14 00:00 UT   06 25 19.6   +19 54 44     1.818    2.771  162.2    6.2    82   11.9 
2026-01-15 00:00 UT   06 24 22.9   +19 57 24     1.822    2.770  161.0    6.6    83   11.9 
2026-01-16 00:00 UT   06 23 27.1   +20 00 04     1.826    2.770  159.8    7.1    83   12.0 
2026-01-17 00:00 UT   06 22 32.3   +20 02 44     1.830    2.769  158.5    7.5    84   12.0 
2026-01-18 00:00 UT   06 21 38.7   +20 05 23     1.835    2.769  157.3    7.9    84   12.0 
2026-01-19 00:00 UT   06 20 46.1   +20 08 02     1.840    2.768  156.1    8.3    85   12.0 
2026-01-20 00:00 UT   06 19 54.8   +20 10 40     1.845    2.768  154.9    8.7    85   12.0 
2026-01-21 00:00 UT   06 19 04.7   +20 13 17     1.850    2.767  153.7    9.1    86   12.1 
2026-01-22 00:00 UT   06 18 15.9   +20 15 54     1.856    2.767  152.5    9.4    86   12.1 
2026-01-23 00:00 UT   06 17 28.5   +20 18 30     1.862    2.766  151.3    9.8    86   12.1 
2026-01-24 00:00 UT   06 16 42.4   +20 21 05     1.868    2.765  150.1   10.2    86   12.1 
2026-01-25 00:00 UT   06 15 57.8   +20 23 39     1.874    2.765  149.0   10.6    87   12.2 
2026-01-26 00:00 UT   06 15 14.7   +20 26 13     1.881    2.764  147.8   10.9    87   12.2 
2026-01-27 00:00 UT   06 14 33.0   +20 28 46     1.888    2.764  146.6   11.3    87   12.2 
2026-01-28 00:00 UT   06 13 52.9   +20 31 18     1.895    2.763  145.4   11.7    87   12.2 
2026-01-29 00:00 UT   06 13 14.4   +20 33 49     1.902    2.763  144.3   12.0    87   12.2 
2026-01-30 00:00 UT   06 12 37.4   +20 36 19     1.910    2.762  143.1   12.4    88   12.3 
2026-01-31 00:00 UT   06 12 02.1   +20 38 48     1.918    2.761  142.0   12.7    88   12.3 
2026-02-01 00:00 UT   06 11 28.4   +20 41 17     1.926    2.761  140.8   13.0    88   12.3 
2026-02-02 00:00 UT   06 10 56.4   +20 43 44     1.934    2.760  139.7   13.3    88   12.3 
2026-02-03 00:00 UT   06 10 26.0   +20 46 11     1.942    2.760  138.6   13.7    88   12.3 
2026-02-04 00:00 UT   06 09 57.3   +20 48 37     1.951    2.759  137.5   14.0    88   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.