(17) Thetis
ephemeris	date	magn	radius	delta	ra	dec	elong	phase
Today	20 May 2025	13.2	2.753 AU	3.760 AU	03h37m	+15°27'	4.9°	1.8°
Opposition	30 Dec 2025	11.6	2.777 AU	1.795 AU	06h40m	+19°15'	176.1°	1.4°

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 Thetis are:

            e (Eccentricity)                : 0.1319544
            a (Semimajor axis)              : 2.4711982
            i (Inclination)                 : 5.59242
            Ω (Longitude of ascending node) : 125.52279
            ω (Argument of perihelion)      : 135.78158
            M (Mean anomaly)                : 142.11870
            Epoch                           : 2025 May 05

            L (Longitude of perihelion)     : 81.44099
            B (Latitude of perihelion)      : 3.89694
            P (Orbital period in years)     : 3.88            
        

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
2025-05-20 00:00 UT   03 37 55.0   +15 27 44     3.760    2.753    4.9    1.8   205   13.2 
2025-05-20 19:18 UT   03 39 14.1   +15 32 27     3.760    2.753    5.2    1.9   209   13.2 
2025-05-21 00:00 UT   03 39 33.4   +15 33 36     3.760    2.753    5.3    1.9   210   13.2 
2025-05-22 00:00 UT   03 41 11.8   +15 39 23     3.760    2.754    5.7    2.1   214   13.2 
2025-05-23 00:00 UT   03 42 50.3   +15 45 07     3.759    2.755    6.1    2.2   218   13.3 
2025-05-24 00:00 UT   03 44 28.8   +15 50 46     3.759    2.755    6.5    2.4   221   13.3 
2025-05-25 00:00 UT   03 46 07.3   +15 56 22     3.759    2.756    7.0    2.6   224   13.3 
2025-05-26 00:00 UT   03 47 45.9   +16 01 54     3.758    2.757    7.4    2.7   226   13.3 
2025-05-27 00:00 UT   03 49 24.6   +16 07 21     3.757    2.757    7.9    2.9   229   13.3 
2025-05-28 00:00 UT   03 51 03.2   +16 12 45     3.756    2.758    8.4    3.1   231   13.3 
2025-05-29 00:00 UT   03 52 41.9   +16 18 04     3.755    2.759    8.9    3.3   233   13.3 
2025-05-30 00:00 UT   03 54 20.5   +16 23 19     3.754    2.759    9.4    3.4   234   13.3 
2025-05-31 00:00 UT   03 55 59.2   +16 28 30     3.753    2.760    9.9    3.6   236   13.3 
2025-06-01 00:00 UT   03 57 37.9   +16 33 37     3.752    2.760   10.4    3.8   237   13.4 
2025-06-02 00:00 UT   03 59 16.6   +16 38 40     3.750    2.761   10.9    4.0   238   13.4 
2025-06-03 00:00 UT   04 00 55.3   +16 43 39     3.748    2.762   11.4    4.2   239   13.4 
2025-06-04 00:00 UT   04 02 34.0   +16 48 33     3.746    2.762   12.0    4.4   240   13.4 
2025-06-05 00:00 UT   04 04 12.7   +16 53 23     3.744    2.763   12.5    4.6   241   13.4 
2025-06-06 00:00 UT   04 05 51.3   +16 58 09     3.742    2.763   13.0    4.7   242   13.4 
2025-06-07 00:00 UT   04 07 30.0   +17 02 51     3.740    2.764   13.6    4.9   243   13.4 
2025-06-08 00:00 UT   04 09 08.6   +17 07 29     3.738    2.764   14.1    5.1   244   13.4 
2025-06-09 00:00 UT   04 10 47.2   +17 12 02     3.735    2.765   14.6    5.3   245   13.4 
2025-06-10 00:00 UT   04 12 25.8   +17 16 31     3.733    2.766   15.2    5.5   245   13.4 

    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.