(404) Arsinoe
ephemeris	date	magn	radius	delta	ra	dec	elong	phase
Today	22 Aug 2026	14.9	3.110 AU	2.949 AU	03h57m	+08°15'	89.6°	19.0°
Opposition	15 Nov 2026	13.6	3.069 AU	2.097 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)                : 0.2017865
            a (Semimajor axis)              : 2.5914457
            i (Inclination)                 : 14.09838
            Ω (Longitude of ascending node) : 92.46291
            ω (Argument of perihelion)      : 120.49000
            M (Mean anomaly)                : 171.14073
            Epoch                           : 2026 Jun 09

            L (Longitude of perihelion)     : 33.72470
            B (Latitude of perihelion)      : 12.11671
            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
2026-08-22 00:00 UT   03 57 36.9   +08 15 51     2.949    3.110   89.6   19.0   258   14.9 
2026-08-22 07:01 UT   03 57 48.2   +08 15 52     2.945    3.110   89.8   19.0   258   14.9 
2026-08-23 00:00 UT   03 58 15.2   +08 15 53     2.935    3.110   90.4   19.0   258   14.9 
2026-08-24 00:00 UT   03 58 52.5   +08 15 50     2.921    3.110   91.2   19.0   258   14.9 
2026-08-25 00:00 UT   03 59 28.9   +08 15 44     2.907    3.110   91.9   19.0   259   14.9 
2026-08-26 00:00 UT   04 00 04.3   +08 15 33     2.892    3.109   92.7   18.9   259   14.9 
2026-08-27 00:00 UT   04 00 38.7   +08 15 18     2.878    3.109   93.6   18.9   259   14.9 
2026-08-28 00:00 UT   04 01 12.2   +08 14 59     2.864    3.109   94.4   18.9   259   14.8 
2026-08-29 00:00 UT   04 01 44.6   +08 14 36     2.850    3.109   95.2   18.9   260   14.8 
2026-08-30 00:00 UT   04 02 16.1   +08 14 09     2.836    3.108   96.0   18.8   260   14.8 
2026-08-31 00:00 UT   04 02 46.5   +08 13 38     2.822    3.108   96.8   18.8   260   14.8 
2026-09-01 00:00 UT   04 03 15.8   +08 13 03     2.808    3.108   97.6   18.8   260   14.8 
2026-09-02 00:00 UT   04 03 44.1   +08 12 23     2.794    3.107   98.5   18.7   260   14.8 
2026-09-03 00:00 UT   04 04 11.4   +08 11 40     2.780    3.107   99.3   18.7   261   14.8 
2026-09-04 00:00 UT   04 04 37.5   +08 10 53     2.766    3.107  100.1   18.6   261   14.8 
2026-09-05 00:00 UT   04 05 02.5   +08 10 02     2.752    3.107  101.0   18.6   261   14.7 
2026-09-06 00:00 UT   04 05 26.4   +08 09 08     2.738    3.106  101.8   18.5   261   14.7 
2026-09-07 00:00 UT   04 05 49.1   +08 08 09     2.725    3.106  102.7   18.5   262   14.7 
2026-09-08 00:00 UT   04 06 10.6   +08 07 07     2.711    3.106  103.6   18.4   262   14.7 
2026-09-09 00:00 UT   04 06 31.0   +08 06 01     2.697    3.105  104.4   18.3   262   14.7 
2026-09-10 00:00 UT   04 06 50.1   +08 04 51     2.683    3.105  105.3   18.2   262   14.7 
2026-09-11 00:00 UT   04 07 08.1   +08 03 38     2.670    3.105  106.2   18.1   263   14.7 
2026-09-12 00:00 UT   04 07 24.8   +08 02 21     2.656    3.104  107.1   18.1   263   14.6 
2026-09-13 00:00 UT   04 07 40.3   +08 01 01     2.642    3.104  107.9   18.0   263   14.6 
2026-09-14 00:00 UT   04 07 54.5   +07 59 37     2.629    3.103  108.8   17.9   263   14.6 
2026-09-15 00:00 UT   04 08 07.5   +07 58 10     2.616    3.103  109.7   17.8   264   14.6 
2026-09-16 00:00 UT   04 08 19.1   +07 56 40     2.602    3.103  110.6   17.7   264   14.6 
2026-09-17 00:00 UT   04 08 29.5   +07 55 07     2.589    3.102  111.5   17.5   264   14.6 
2026-09-18 00:00 UT   04 08 38.6   +07 53 31     2.576    3.102  112.5   17.4   264   14.6 
2026-09-19 00:00 UT   04 08 46.3   +07 51 51     2.563    3.102  113.4   17.3   265   14.5 
2026-09-20 00:00 UT   04 08 52.7   +07 50 09     2.550    3.101  114.3   17.2   265   14.5 
2026-09-21 00:00 UT   04 08 57.8   +07 48 24     2.537    3.101  115.2   17.0   265   14.5 

    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.