(259) Aletheia
ephemeris	date	magn	radius	delta	ra	dec	elong	phase
Today	29 May 2025	11.4	2.727 AU	1.717 AU	16h40m	-17°01'	173.9°	2.3°
Opposition	31 May 2025	11.4	2.727 AU	1.715 AU	16h38m	-17°07'	175.0°	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 Aletheia are:

            e (Eccentricity)                : 0.1299188
            a (Semimajor axis)              : 3.1334338
            i (Inclination)                 : 10.80855
            Ω (Longitude of ascending node) : 86.78078
            ω (Argument of perihelion)      : 166.37237
            M (Mean anomaly)                : 352.85984
            Epoch                           : 2025 May 05

            L (Longitude of perihelion)     : 73.38613
            B (Latitude of perihelion)      : 2.53236
            P (Orbital period in years)     : 5.55            
        

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
2025-05-29 00:00 UT   16 40 26.9   -17 01 36     1.717    2.727  173.9    2.3   222   11.4 
2025-05-29 03:22 UT   16 40 19.6   -17 01 54     1.717    2.727  174.0    2.2   220   11.4 
2025-05-30 00:00 UT   16 39 34.5   -17 03 44     1.716    2.727  174.5    2.0   212   11.4 
2025-05-31 00:00 UT   16 38 41.8   -17 05 55     1.716    2.727  174.9    1.9   200   11.4 
2025-06-01 00:00 UT   16 37 49.1   -17 08 07     1.715    2.727  175.1    1.8   187   11.4 
2025-06-02 00:00 UT   16 36 56.3   -17 10 21     1.715    2.727  175.0    1.9   174   11.4 
2025-06-03 00:00 UT   16 36 03.5   -17 12 37     1.715    2.727  174.7    2.0   161   11.4 
2025-06-04 00:00 UT   16 35 10.7   -17 14 55     1.716    2.727  174.1    2.2   151   11.4 
2025-06-05 00:00 UT   16 34 18.2   -17 17 16     1.716    2.727  173.4    2.5   143   11.5 
2025-06-06 00:00 UT   16 33 25.8   -17 19 38     1.717    2.727  172.5    2.8   136   11.5 
2025-06-07 00:00 UT   16 32 33.7   -17 22 02     1.718    2.726  171.6    3.1   131   11.5 
2025-06-08 00:00 UT   16 31 41.9   -17 24 29     1.720    2.726  170.7    3.5   127   11.5 
2025-06-09 00:00 UT   16 30 50.5   -17 26 57     1.722    2.726  169.7    3.8   123   11.5 
2025-06-10 00:00 UT   16 29 59.5   -17 29 28     1.724    2.726  168.7    4.2   121   11.6 
2025-06-11 00:00 UT   16 29 09.0   -17 32 00     1.726    2.726  167.6    4.6   118   11.6 
2025-06-12 00:00 UT   16 28 19.0   -17 34 35     1.729    2.726  166.6    5.0   117   11.6 
2025-06-13 00:00 UT   16 27 29.7   -17 37 12     1.731    2.726  165.5    5.4   115   11.6 
2025-06-14 00:00 UT   16 26 40.9   -17 39 50     1.734    2.726  164.4    5.7   114   11.7 
2025-06-15 00:00 UT   16 25 52.9   -17 42 31     1.738    2.726  163.3    6.1   112   11.7 
2025-06-16 00:00 UT   16 25 05.7   -17 45 14     1.741    2.726  162.2    6.5   111   11.7 
2025-06-17 00:00 UT   16 24 19.2   -17 47 60     1.745    2.726  161.2    6.9   110   11.7 
2025-06-18 00:00 UT   16 23 33.6   -17 50 47     1.749    2.726  160.1    7.3   110   11.8 
2025-06-19 00:00 UT   16 22 48.9   -17 53 36     1.754    2.726  159.0    7.7   109   11.8 
2025-06-20 00:00 UT   16 22 05.2   -17 56 28     1.758    2.726  157.9    8.1   108   11.8 
2025-06-21 00:00 UT   16 21 22.4   -17 59 22     1.763    2.726  156.8    8.4   108   11.8 
2025-06-22 00:00 UT   16 20 40.7   -18 02 18     1.768    2.726  155.7    8.8   107   11.8 
2025-06-23 00:00 UT   16 20 00.1   -18 05 17     1.773    2.727  154.6    9.2   107   11.9 
2025-06-24 00:00 UT   16 19 20.6   -18 08 17     1.779    2.727  153.5    9.6   106   11.9 
2025-06-25 00:00 UT   16 18 42.3   -18 11 20     1.785    2.727  152.5    9.9   106   11.9 
2025-06-26 00:00 UT   16 18 05.2   -18 14 26     1.791    2.727  151.4   10.3   106   11.9 
2025-06-27 00:00 UT   16 17 29.3   -18 17 34     1.797    2.727  150.3   10.6   105   12.0 
2025-06-28 00:00 UT   16 16 54.7   -18 20 44     1.803    2.727  149.2   11.0   105   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.