(404) Arsinoe
ephemeris	date	magn	radius	delta	ra	dec	elong	phase
Today	15 May 2026	15.2	3.102 AU	3.990 AU	02h09m	+02°12'	24.9°	7.9°
Opposition	15 Nov 2026	13.6	3.069 AU	2.098 AU	03h39m	+05°57'	166.8°	4.2°

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 Arsinoe are:

            e (Eccentricity)                : 0.2016098
            a (Semimajor axis)              : 2.5918971
            i (Inclination)                 : 14.09820
            Ω (Longitude of ascending node) : 92.46743
            ω (Argument of perihelion)      : 120.51372
            M (Mean anomaly)                : 123.86510
            Epoch                           : 2025 Nov 21

            L (Longitude of perihelion)     : 33.75326
            B (Latitude of perihelion)      : 12.11356
            P (Orbital period in years)     : 4.17            
        

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
2026-05-15 00:00 UT   02 09 31.2   +02 12 33     3.990    3.102   24.9    7.9   227   15.2 
2026-05-15 21:31 UT   02 10 42.1   +02 18 48     3.985    3.103   25.4    8.0   228   15.2 
2026-05-16 00:00 UT   02 10 50.3   +02 19 31     3.985    3.103   25.5    8.1   228   15.2 
2026-05-17 00:00 UT   02 12 09.3   +02 26 26     3.980    3.103   26.0    8.2   229   15.2 
2026-05-18 00:00 UT   02 13 28.2   +02 33 17     3.975    3.104   26.6    8.4   229   15.2 
2026-05-19 00:00 UT   02 14 46.9   +02 40 05     3.969    3.104   27.2    8.6   230   15.2 
2026-05-20 00:00 UT   02 16 05.6   +02 46 49     3.964    3.104   27.7    8.7   230   15.2 
2026-05-21 00:00 UT   02 17 24.1   +02 53 30     3.958    3.105   28.3    8.9   231   15.2 
2026-05-22 00:00 UT   02 18 42.5   +03 00 07     3.953    3.105   28.9    9.1   231   15.2 
2026-05-23 00:00 UT   02 20 00.8   +03 06 41     3.947    3.105   29.4    9.2   232   15.2 
2026-05-24 00:00 UT   02 21 19.0   +03 13 11     3.941    3.106   30.0    9.4   232   15.2 
2026-05-25 00:00 UT   02 22 37.0   +03 19 37     3.935    3.106   30.6    9.6   233   15.2 
2026-05-26 00:00 UT   02 23 54.9   +03 25 60     3.928    3.106   31.2    9.7   233   15.2 
2026-05-27 00:00 UT   02 25 12.6   +03 32 19     3.922    3.107   31.8    9.9   234   15.2 
2026-05-28 00:00 UT   02 26 30.2   +03 38 34     3.915    3.107   32.3   10.0   234   15.2 
2026-05-29 00:00 UT   02 27 47.6   +03 44 46     3.909    3.107   32.9   10.2   235   15.2 
2026-05-30 00:00 UT   02 29 04.9   +03 50 53     3.902    3.107   33.5   10.4   235   15.2 
2026-05-31 00:00 UT   02 30 22.1   +03 56 58     3.895    3.108   34.1   10.5   236   15.2 
2026-06-01 00:00 UT   02 31 39.1   +04 02 58     3.888    3.108   34.7   10.7   236   15.2 
2026-06-02 00:00 UT   02 32 55.9   +04 08 55     3.881    3.108   35.3   10.9   237   15.2 
2026-06-03 00:00 UT   02 34 12.5   +04 14 47     3.873    3.109   35.9   11.0   237   15.2 
2026-06-04 00:00 UT   02 35 29.0   +04 20 36     3.866    3.109   36.4   11.2   237   15.2 
2026-06-05 00:00 UT   02 36 45.3   +04 26 22     3.858    3.109   37.0   11.3   238   15.2 
2026-06-06 00:00 UT   02 38 01.5   +04 32 03     3.850    3.109   37.6   11.5   238   15.2 
2026-06-07 00:00 UT   02 39 17.4   +04 37 40     3.843    3.110   38.2   11.7   238   15.2 
2026-06-08 00:00 UT   02 40 33.2   +04 43 14     3.835    3.110   38.8   11.8   239   15.2 
2026-06-09 00:00 UT   02 41 48.8   +04 48 43     3.826    3.110   39.4   12.0   239   15.2 

    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.