2009 BG81
ephemeris	date	magn	radius	delta	ra	dec	elong	phase
Today	22 Apr 2026	30.9	1.599 AU	1.235 AU	20h10m	-17°08'	90.5°	38.9°

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 2009 BG81 are:

            e (Eccentricity)                : 0.4597177
            a (Semimajor axis)              : 1.7952137
            i (Inclination)                 : 3.05071
            Ω (Longitude of ascending node) : 128.24596
            ω (Argument of perihelion)      : 29.35556
            M (Mean anomaly)                : 348.36487
            Epoch                           : 2025 Nov 21

            L (Longitude of perihelion)     : 157.56681
            B (Latitude of perihelion)      : 1.49501
            P (Orbital period in years)     : 2.41            
        

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
2026-04-22 00:00 UT   20 10 26.4   -17 08 39     1.235    1.599   90.5   38.9   258   30.9 
2026-04-22 13:55 UT   20 11 05.7   -17 06 37     1.233    1.603   90.9   38.8   258   30.9 
2026-04-23 00:00 UT   20 11 33.8   -17 05 10     1.231    1.605   91.2   38.8   257   30.9 
2026-04-24 00:00 UT   20 12 39.0   -17 01 46     1.227    1.612   91.9   38.6   257   30.9 
2026-04-25 00:00 UT   20 13 42.2   -16 58 28     1.222    1.618   92.6   38.4   257   30.9 
2026-04-26 00:00 UT   20 14 43.2   -16 55 16     1.218    1.624   93.3   38.2   257   30.9 
2026-04-27 00:00 UT   20 15 42.0   -16 52 10     1.214    1.631   94.1   38.0   257   30.9 
2026-04-28 00:00 UT   20 16 38.6   -16 49 09     1.210    1.637   94.8   37.8   257   30.9 
2026-04-29 00:00 UT   20 17 33.1   -16 46 16     1.205    1.644   95.5   37.6   257   30.9 
2026-04-30 00:00 UT   20 18 25.3   -16 43 29     1.201    1.650   96.3   37.4   257   30.9 
2026-05-01 00:00 UT   20 19 15.3   -16 40 48     1.196    1.656   97.1   37.1   257   30.9 
2026-05-02 00:00 UT   20 20 03.1   -16 38 15     1.192    1.662   97.8   36.9   256   30.9 
2026-05-03 00:00 UT   20 20 48.5   -16 35 49     1.187    1.669   98.6   36.7   256   30.9 
2026-05-04 00:00 UT   20 21 31.7   -16 33 31     1.183    1.675   99.4   36.4   256   30.9 
2026-05-05 00:00 UT   20 22 12.5   -16 31 20     1.178    1.681  100.2   36.2   256   30.9 
2026-05-06 00:00 UT   20 22 51.0   -16 29 17     1.174    1.687  101.0   35.9   256   30.9 
2026-05-07 00:00 UT   20 23 27.2   -16 27 23     1.169    1.694  101.8   35.7   256   30.8 
2026-05-08 00:00 UT   20 24 00.9   -16 25 36     1.164    1.700  102.7   35.4   256   30.8 
2026-05-09 00:00 UT   20 24 32.2   -16 23 58     1.160    1.706  103.5   35.1   256   30.8 
2026-05-10 00:00 UT   20 25 01.0   -16 22 29     1.155    1.712  104.4   34.8   256   30.8 
2026-05-11 00:00 UT   20 25 27.4   -16 21 09     1.150    1.718  105.2   34.5   256   30.8 
2026-05-12 00:00 UT   20 25 51.3   -16 19 58     1.146    1.725  106.1   34.2   256   30.8 
2026-05-13 00:00 UT   20 26 12.6   -16 18 57     1.141    1.731  107.0   33.9   255   30.8 
2026-05-14 00:00 UT   20 26 31.4   -16 18 05     1.136    1.737  107.9   33.6   255   30.8 
2026-05-15 00:00 UT   20 26 47.6   -16 17 23     1.131    1.743  108.8   33.3   255   30.8 
2026-05-16 00:00 UT   20 27 01.2   -16 16 51     1.127    1.749  109.7   33.0   255   30.8 
2026-05-17 00:00 UT   20 27 12.2   -16 16 29     1.122    1.755  110.6   32.6   255   30.7 
2026-05-18 00:00 UT   20 27 20.6   -16 16 17     1.118    1.761  111.5   32.3   255   30.7 
2026-05-19 00:00 UT   20 27 26.2   -16 16 15     1.113    1.767  112.5   31.9   255   30.7 
2026-05-20 00:00 UT   20 27 29.2   -16 16 24     1.108    1.773  113.4   31.6   255   30.7 
2026-05-21 00:00 UT   20 27 29.5   -16 16 44     1.104    1.779  114.4   31.2   255   30.7 
2026-05-22 00:00 UT   20 27 27.1   -16 17 14     1.099    1.785  115.3   30.8   255   30.7 

    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.