(404) Arsinoe
ephemeris	date	magn	radius	delta	ra	dec	elong	phase
Today	15 Apr 2026	15.0	3.088 AU	4.066 AU	01h29m	-01°40'	11.2°	3.6°
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
2026-04-15 00:00 UT   01 29 28.6   -01 40 49     4.066    3.088   11.2    3.6   182   15.0 
2026-04-15 21:31 UT   01 30 40.9   -01 33 14     4.065    3.089   11.5    3.7   185   15.0 
2026-04-16 00:00 UT   01 30 49.2   -01 32 21     4.065    3.089   11.5    3.7   185   15.0 
2026-04-17 00:00 UT   01 32 09.9   -01 23 56     4.065    3.089   11.8    3.8   188   15.0 
2026-04-18 00:00 UT   01 33 30.5   -01 15 33     4.064    3.090   12.1    3.9   191   15.0 
2026-04-19 00:00 UT   01 34 51.1   -01 07 12     4.064    3.090   12.4    4.0   193   15.0 
2026-04-20 00:00 UT   01 36 11.7   +00 58 55     4.063    3.091   12.8    4.1   195   15.0 
2026-04-21 00:00 UT   01 37 32.2   +00 50 40     4.061    3.091   13.1    4.2   198   15.0 
2026-04-22 00:00 UT   01 38 52.8   +00 42 28     4.060    3.092   13.5    4.4   200   15.0 
2026-04-23 00:00 UT   01 40 13.3   +00 34 18     4.059    3.092   13.9    4.5   202   15.0 
2026-04-24 00:00 UT   01 41 33.7   +00 26 12     4.057    3.093   14.3    4.6   204   15.0 
2026-04-25 00:00 UT   01 42 54.1   +00 18 08     4.055    3.093   14.8    4.8   205   15.0 
2026-04-26 00:00 UT   01 44 14.5   +00 10 07     4.054    3.094   15.2    4.9   207   15.0 
2026-04-27 00:00 UT   01 45 34.9   +00 02 10     4.052    3.094   15.7    5.0   209   15.0 
2026-04-28 00:00 UT   01 46 55.2   +00 05 45     4.049    3.095   16.1    5.2   210   15.1 
2026-04-29 00:00 UT   01 48 15.4   +00 13 38     4.047    3.095   16.6    5.3   212   15.1 
2026-04-30 00:00 UT   01 49 35.6   +00 21 27     4.045    3.096   17.1    5.5   213   15.1 
2026-05-01 00:00 UT   01 50 55.8   +00 29 13     4.042    3.096   17.6    5.6   214   15.1 
2026-05-02 00:00 UT   01 52 15.8   +00 36 56     4.039    3.097   18.0    5.8   216   15.1 
2026-05-03 00:00 UT   01 53 35.9   +00 44 36     4.036    3.097   18.5    5.9   217   15.1 
2026-05-04 00:00 UT   01 54 55.9   +00 52 13     4.033    3.098   19.1    6.1   218   15.1 
2026-05-05 00:00 UT   01 56 15.8   +00 59 47     4.030    3.098   19.6    6.3   219   15.1 
2026-05-06 00:00 UT   01 57 35.7   +01 07 18     4.027    3.099   20.1    6.4   220   15.1 
2026-05-07 00:00 UT   01 58 55.5   +01 14 46     4.023    3.099   20.6    6.6   221   15.1 
2026-05-08 00:00 UT   02 00 15.2   +01 22 11     4.019    3.100   21.1    6.7   222   15.1 

    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.