(415029) 2011 UL21
ephemeris	date	magn	radius	delta	ra	dec	elong	phase
Today	7 Dec 2025	22.0	3.509 AU	3.100 AU	23h10m	+37°11'	106.5°	15.6°

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 2011 UL21 are:

            e (Eccentricity)                : 0.6537389
            a (Semimajor axis)              : 2.1223847
            i (Inclination)                 : 34.88596
            Ω (Longitude of ascending node) : 275.31457
            ω (Argument of perihelion)      : 284.98019
            M (Mean anomaly)                : 177.74571
            Epoch                           : 2025 Nov 21

            L (Longitude of perihelion)     : 203.38086
            B (Latitude of perihelion)      : -33.53921
            P (Orbital period in years)     : 3.09            
        

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
2025-12-07 00:00 UT   23 10 02.7   +37 11 23     3.100    3.509  106.5   15.6    74   22.0 
2025-12-07 04:34 UT   23 10 07.1   +37 09 25     3.102    3.509  106.3   15.6    74   22.0 
2025-12-08 00:00 UT   23 10 26.3   +37 01 10     3.111    3.509  105.7   15.7    73   22.0 
2025-12-09 00:00 UT   23 10 51.1   +36 51 07     3.123    3.509  105.0   15.7    73   22.0 
2025-12-10 00:00 UT   23 11 17.1   +36 41 13     3.134    3.509  104.2   15.8    72   22.0 
2025-12-11 00:00 UT   23 11 44.3   +36 31 29     3.146    3.509  103.5   15.8    71   22.0 
2025-12-12 00:00 UT   23 12 12.7   +36 21 56     3.157    3.508  102.7   15.9    71   22.0 
2025-12-13 00:00 UT   23 12 42.2   +36 12 32     3.169    3.508  102.0   15.9    70   22.0 
2025-12-14 00:00 UT   23 13 12.9   +36 03 18     3.181    3.508  101.2   16.0    69   22.0 
2025-12-15 00:00 UT   23 13 44.7   +35 54 15     3.192    3.508  100.5   16.0    69   22.0 
2025-12-16 00:00 UT   23 14 17.5   +35 45 21     3.204    3.507   99.7   16.1    68   22.1 
2025-12-17 00:00 UT   23 14 51.5   +35 36 38     3.216    3.507   99.0   16.1    68   22.1 
2025-12-18 00:00 UT   23 15 26.5   +35 28 06     3.228    3.507   98.2   16.1    67   22.1 
2025-12-19 00:00 UT   23 16 02.6   +35 19 44     3.240    3.506   97.4   16.2    67   22.1 
2025-12-20 00:00 UT   23 16 39.7   +35 11 33     3.253    3.506   96.7   16.2    66   22.1 
2025-12-21 00:00 UT   23 17 17.7   +35 03 32     3.265    3.506   95.9   16.2    65   22.1 
2025-12-22 00:00 UT   23 17 56.8   +34 55 42     3.277    3.505   95.2   16.2    65   22.1 
2025-12-23 00:00 UT   23 18 36.9   +34 48 03     3.289    3.505   94.4   16.2    64   22.1 
2025-12-24 00:00 UT   23 19 17.8   +34 40 34     3.302    3.505   93.7   16.3    64   22.1 
2025-12-25 00:00 UT   23 19 59.8   +34 33 16     3.314    3.504   92.9   16.3    63   22.1 
2025-12-26 00:00 UT   23 20 42.6   +34 26 09     3.326    3.504   92.2   16.3    63   22.1 
2025-12-27 00:00 UT   23 21 26.3   +34 19 12     3.339    3.503   91.4   16.3    62   22.1 
2025-12-28 00:00 UT   23 22 10.9   +34 12 26     3.351    3.503   90.6   16.3    62   22.2 
2025-12-29 00:00 UT   23 22 56.3   +34 05 51     3.363    3.502   89.9   16.3    61   22.2 
2025-12-30 00:00 UT   23 23 42.6   +33 59 26     3.376    3.502   89.1   16.3    61   22.2 
2025-12-31 00:00 UT   23 24 29.7   +33 53 12     3.388    3.501   88.4   16.3    61   22.2 
2026-01-01 00:00 UT   23 25 17.6   +33 47 09     3.401    3.501   87.6   16.3    60   22.2 
2026-01-02 00:00 UT   23 26 06.3   +33 41 15     3.413    3.500   86.9   16.3    60   22.2 
2026-01-03 00:00 UT   23 26 55.8   +33 35 33     3.426    3.500   86.1   16.3    59   22.2 
2026-01-04 00:00 UT   23 27 46.0   +33 30 00     3.438    3.499   85.4   16.3    59   22.2 
2026-01-05 00:00 UT   23 28 37.0   +33 24 38     3.450    3.499   84.7   16.3    58   22.2 
2026-01-06 00:00 UT   23 29 28.7   +33 19 27     3.463    3.498   83.9   16.2    58   22.2 

    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.