(423) Diotima
ephemeris	date	magn	radius	delta	ra	dec	elong	phase
Today	2 Oct 2025	12.6	3.139 AU	2.404 AU	03h51m	+13°46'	129.7°	14.2°
Opposition	14 Nov 2025	11.7	3.149 AU	2.162 AU	03h23m	+13°29'	175.1°	1.6°

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 Diotima are:

            e (Eccentricity)                : 0.0338729
            a (Semimajor axis)              : 3.0667835
            i (Inclination)                 : 11.24258
            Ω (Longitude of ascending node) : 69.34900
            ω (Argument of perihelion)      : 199.08736
            M (Mean anomaly)                : 142.07248
            Epoch                           : 2025 Nov 21

            L (Longitude of perihelion)     : 88.09589
            B (Latitude of perihelion)      : -3.65536
            P (Orbital period in years)     : 5.37            
        

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
2025-10-02 00:00 UT   03 51 31.9   +13 46 56     2.404    3.139  129.7   14.2   263   12.6 
2025-10-02 20:06 UT   03 51 20.3   +13 46 60     2.395    3.140  130.6   14.0   263   12.6 
2025-10-03 00:00 UT   03 51 17.9   +13 47 00     2.393    3.140  130.7   14.0   263   12.6 
2025-10-04 00:00 UT   03 51 02.4   +13 47 02     2.383    3.140  131.8   13.7   263   12.5 
2025-10-05 00:00 UT   03 50 45.6   +13 47 02     2.373    3.140  132.8   13.5   263   12.5 
2025-10-06 00:00 UT   03 50 27.3   +13 46 60     2.363    3.140  133.9   13.3   264   12.5 
2025-10-07 00:00 UT   03 50 07.7   +13 46 56     2.354    3.140  134.9   13.0   264   12.5 
2025-10-08 00:00 UT   03 49 46.8   +13 46 49     2.344    3.141  136.0   12.8   264   12.5 
2025-10-09 00:00 UT   03 49 24.4   +13 46 41     2.335    3.141  137.0   12.5   264   12.5 
2025-10-10 00:00 UT   03 49 00.7   +13 46 30     2.326    3.141  138.1   12.3   264   12.4 
2025-10-11 00:00 UT   03 48 35.7   +13 46 18     2.317    3.141  139.2   12.0   265   12.4 
2025-10-12 00:00 UT   03 48 09.3   +13 46 03     2.308    3.142  140.3   11.7   265   12.4 
2025-10-13 00:00 UT   03 47 41.6   +13 45 47     2.300    3.142  141.4   11.4   265   12.4 
2025-10-14 00:00 UT   03 47 12.6   +13 45 29     2.292    3.142  142.5   11.2   265   12.4 
2025-10-15 00:00 UT   03 46 42.3   +13 45 10     2.284    3.142  143.6   10.9   266   12.3 
2025-10-16 00:00 UT   03 46 10.7   +13 44 48     2.276    3.143  144.7   10.6   266   12.3 
2025-10-17 00:00 UT   03 45 37.8   +13 44 26     2.268    3.143  145.8   10.3   266   12.3 
2025-10-18 00:00 UT   03 45 03.7   +13 44 01     2.261    3.143  146.9   10.0   266   12.3 
2025-10-19 00:00 UT   03 44 28.4   +13 43 35     2.254    3.143  148.0    9.7   267   12.3 
2025-10-20 00:00 UT   03 43 51.9   +13 43 08     2.247    3.143  149.1    9.4   267   12.2 
2025-10-21 00:00 UT   03 43 14.2   +13 42 40     2.240    3.144  150.2    9.0   267   12.2 
2025-10-22 00:00 UT   03 42 35.4   +13 42 11     2.234    3.144  151.4    8.7   268   12.2 
2025-10-23 00:00 UT   03 41 55.5   +13 41 40     2.228    3.144  152.5    8.4   268   12.2 
2025-10-24 00:00 UT   03 41 14.6   +13 41 09     2.222    3.144  153.6    8.1   269   12.2 
2025-10-25 00:00 UT   03 40 32.6   +13 40 36     2.216    3.144  154.8    7.7   269   12.1 
2025-10-26 00:00 UT   03 39 49.6   +13 40 03     2.211    3.145  155.9    7.4   270   12.1 
2025-10-27 00:00 UT   03 39 05.7   +13 39 30     2.206    3.145  157.1    7.1   270   12.1 
2025-10-28 00:00 UT   03 38 20.8   +13 38 55     2.201    3.145  158.2    6.7   271   12.1 
2025-10-29 00:00 UT   03 37 35.1   +13 38 21     2.196    3.145  159.4    6.4   272   12.1 
2025-10-30 00:00 UT   03 36 48.5   +13 37 46     2.192    3.146  160.5    6.0   273   12.0 
2025-10-31 00:00 UT   03 36 01.1   +13 37 10     2.188    3.146  161.7    5.7   273   12.0 
2025-11-01 00:00 UT   03 35 13.0   +13 36 35     2.184    3.146  162.8    5.4   275   12.0 

    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.