2009 BG81
ephemeris	date	magn	radius	delta	ra	dec	elong	phase
Today	22 May 2026	30.7	1.785 AU	1.099 AU	20h27m	-16°17'	115.3°	30.8°

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
2026-05-22 00:00 UT   20 27 27.1   -16 17 14     1.099    1.785  115.3   30.8   255   30.7 
2026-05-22 15:25 UT   20 27 24.2   -16 17 40     1.097    1.789  116.0   30.6   255   30.7 
2026-05-23 00:00 UT   20 27 22.0   -16 17 56     1.095    1.791  116.3   30.4   255   30.7 
2026-05-24 00:00 UT   20 27 14.2   -16 18 48     1.091    1.797  117.3   30.0   255   30.7 
2026-05-25 00:00 UT   20 27 03.6   -16 19 50     1.086    1.803  118.3   29.6   255   30.6 
2026-05-26 00:00 UT   20 26 50.3   -16 21 04     1.082    1.808  119.3   29.2   255   30.6 
2026-05-27 00:00 UT   20 26 34.3   -16 22 29     1.078    1.814  120.4   28.8   255   30.6 
2026-05-28 00:00 UT   20 26 15.5   -16 24 04     1.074    1.820  121.4   28.4   255   30.6 
2026-05-29 00:00 UT   20 25 53.9   -16 25 51     1.069    1.826  122.4   27.9   255   30.6 
2026-05-30 00:00 UT   20 25 29.6   -16 27 48     1.065    1.832  123.5   27.5   255   30.6 
2026-05-31 00:00 UT   20 25 02.4   -16 29 56     1.062    1.837  124.6   27.0   255   30.6 
2026-06-01 00:00 UT   20 24 32.6   -16 32 16     1.058    1.843  125.7   26.5   255   30.5 
2026-06-02 00:00 UT   20 23 59.9   -16 34 46     1.054    1.849  126.8   26.1   254   30.5 
2026-06-03 00:00 UT   20 23 24.5   -16 37 26     1.050    1.855  127.9   25.6   254   30.5 
2026-06-04 00:00 UT   20 22 46.3   -16 40 18     1.047    1.860  129.0   25.1   254   30.5 
2026-06-05 00:00 UT   20 22 05.4   -16 43 20     1.043    1.866  130.1   24.6   254   30.5 
2026-06-06 00:00 UT   20 21 21.7   -16 46 32     1.040    1.872  131.2   24.1   254   30.5 
2026-06-07 00:00 UT   20 20 35.3   -16 49 55     1.037    1.877  132.4   23.5   254   30.5 
2026-06-08 00:00 UT   20 19 46.2   -16 53 28     1.034    1.883  133.5   23.0   254   30.4 
2026-06-09 00:00 UT   20 18 54.4   -16 57 11     1.031    1.888  134.7   22.5   254   30.4 
2026-06-10 00:00 UT   20 17 60.0   -17 01 03     1.028    1.894  135.9   21.9   254   30.4 
2026-06-11 00:00 UT   20 17 02.9   -17 05 06     1.026    1.900  137.1   21.3   254   30.4 
2026-06-12 00:00 UT   20 16 03.2   -17 09 17     1.023    1.905  138.3   20.8   254   30.4 
2026-06-13 00:00 UT   20 15 01.0   -17 13 38     1.021    1.911  139.5   20.2   254   30.4 
2026-06-14 00:00 UT   20 13 56.3   -17 18 07     1.019    1.916  140.7   19.6   254   30.3 
2026-06-15 00:00 UT   20 12 49.1   -17 22 44     1.017    1.922  142.0   19.0   254   30.3 
2026-06-16 00:00 UT   20 11 39.6   -17 27 30     1.015    1.927  143.2   18.4   254   30.3 
2026-06-17 00:00 UT   20 10 27.7   -17 32 23     1.013    1.932  144.4   17.8   254   30.3 
2026-06-18 00:00 UT   20 09 13.6   -17 37 23     1.012    1.938  145.7   17.2   254   30.3 
2026-06-19 00:00 UT   20 07 57.3   -17 42 31     1.011    1.943  147.0   16.6   254   30.3 
2026-06-20 00:00 UT   20 06 39.0   -17 47 44     1.010    1.949  148.2   15.9   254   30.2 
2026-06-21 00:00 UT   20 05 18.7   -17 53 03     1.009    1.954  149.5   15.3   254   30.2 

    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.