2021 AO4
ephemeris	date	magn	radius	delta	ra	dec	elong	phase
Today	26 Sep 2026	31.4	1.712 AU	2.695 AU	12h12m	+08°05'	9.1°	5.3°

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 2021 AO4 are:

            e (Eccentricity)                : 0.4473349
            a (Semimajor axis)              : 1.2101429
            i (Inclination)                 : 14.42772
            Ω (Longitude of ascending node) : 106.75551
            ω (Argument of perihelion)      : 265.20135
            M (Mean anomaly)                : 67.86748
            Epoch                           : 2026 Jun 09

            L (Longitude of perihelion)     : 191.80136
            B (Latitude of perihelion)      : -14.37606
            P (Orbital period in years)     : 1.33            
        

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
2026-09-26 00:00 UT   12 12 16.2   +08 05 28     2.695    1.712    9.1    5.3     5   31.4 
2026-09-26 02:45 UT   12 12 31.0   +08 04 02     2.695    1.713    9.2    5.3     4   31.4 
2026-09-27 00:00 UT   12 14 25.3   +07 52 57     2.696    1.714    9.3    5.4     2   31.4 
2026-09-28 00:00 UT   12 16 34.2   +07 40 28     2.697    1.716    9.5    5.5   360   31.4 
2026-09-29 00:00 UT   12 18 42.9   +07 27 59     2.697    1.718    9.7    5.6   358   31.4 
2026-09-30 00:00 UT   12 20 51.5   +07 15 32     2.698    1.720    9.9    5.7   356   31.4 
2026-10-01 00:00 UT   12 22 59.9   +07 03 05     2.698    1.721   10.1    5.8   354   31.4 
2026-10-02 00:00 UT   12 25 08.1   +06 50 39     2.698    1.723   10.3    6.0   352   31.4 
2026-10-03 00:00 UT   12 27 16.2   +06 38 15     2.698    1.724   10.5    6.1   350   31.5 
2026-10-04 00:00 UT   12 29 24.1   +06 25 52     2.698    1.726   10.8    6.2   348   31.5 
2026-10-05 00:00 UT   12 31 31.9   +06 13 30     2.698    1.727   11.0    6.4   346   31.5 
2026-10-06 00:00 UT   12 33 39.6   +06 01 09     2.698    1.729   11.3    6.5   345   31.5 
2026-10-07 00:00 UT   12 35 47.1   +05 48 50     2.698    1.730   11.6    6.7   343   31.5 
2026-10-08 00:00 UT   12 37 54.6   +05 36 32     2.697    1.731   11.9    6.8   342   31.5 
2026-10-09 00:00 UT   12 40 01.9   +05 24 16     2.697    1.733   12.2    7.0   340   31.5 
2026-10-10 00:00 UT   12 42 09.1   +05 12 01     2.696    1.734   12.5    7.1   339   31.5 

    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.