2021 SF1
ephemeris	date	magn	radius	delta	ra	dec	elong	phase
Today	10 Aug 2026	27.2	1.228 AU	0.362 AU	16h57m	-19°59'	118.3°	46.6°

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 2021 SF1 are:

            e (Eccentricity)                : 0.1677477
            a (Semimajor axis)              : 1.1717045
            i (Inclination)                 : 0.79407
            Ω (Longitude of ascending node) : 204.29908
            ω (Argument of perihelion)      : 213.28442
            M (Mean anomaly)                : 59.09265
            Epoch                           : 2025 Nov 21

            L (Longitude of perihelion)     : 237.58098
            B (Latitude of perihelion)      : -0.43577
            P (Orbital period in years)     : 1.27            
        

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
2026-08-10 00:00 UT   16 57 52.2   -19 59 31     0.362    1.228  118.3   46.6    98   27.2 
2026-08-10 17:09 UT   16 58 09.2   -20 01 09     0.364    1.226  117.7   47.1    97   27.2 
2026-08-11 00:00 UT   16 58 16.5   -20 01 49     0.364    1.225  117.5   47.2    97   27.2 
2026-08-12 00:00 UT   16 58 45.0   -20 04 12     0.367    1.223  116.6   47.8    97   27.2 
2026-08-13 00:00 UT   16 59 17.5   -20 06 42     0.369    1.220  115.8   48.4    97   27.3 
2026-08-14 00:00 UT   16 59 54.0   -20 09 17     0.372    1.218  115.0   48.9    97   27.3 
2026-08-15 00:00 UT   17 00 34.4   -20 11 57     0.374    1.215  114.2   49.5    97   27.3 
2026-08-16 00:00 UT   17 01 18.6   -20 14 41     0.377    1.213  113.4   50.0    97   27.4 
2026-08-17 00:00 UT   17 02 06.6   -20 17 30     0.379    1.210  112.6   50.5    97   27.4 
2026-08-18 00:00 UT   17 02 58.3   -20 20 23     0.382    1.208  111.9   51.1    97   27.4 
2026-08-19 00:00 UT   17 03 53.6   -20 23 20     0.384    1.205  111.2   51.6    96   27.4 
2026-08-20 00:00 UT   17 04 52.4   -20 26 20     0.386    1.203  110.4   52.1    96   27.4 
2026-08-21 00:00 UT   17 05 54.7   -20 29 22     0.389    1.200  109.7   52.5    96   27.5 
2026-08-22 00:00 UT   17 07 00.3   -20 32 28     0.391    1.197  109.0   53.0    96   27.5 
2026-08-23 00:00 UT   17 08 09.3   -20 35 35     0.393    1.195  108.3   53.5    96   27.5 
2026-08-24 00:00 UT   17 09 21.4   -20 38 44     0.396    1.192  107.6   53.9    96   27.5 
2026-08-25 00:00 UT   17 10 36.7   -20 41 54     0.398    1.190  107.0   54.4    96   27.6 
2026-08-26 00:00 UT   17 11 55.1   -20 45 05     0.400    1.187  106.3   54.8    95   27.6 
2026-08-27 00:00 UT   17 13 16.5   -20 48 17     0.402    1.184  105.7   55.2    95   27.6 
2026-08-28 00:00 UT   17 14 40.9   -20 51 29     0.405    1.182  105.0   55.6    95   27.6 
2026-08-29 00:00 UT   17 16 08.2   -20 54 41     0.407    1.179  104.4   56.1    95   27.6 
2026-08-30 00:00 UT   17 17 38.2   -20 57 53     0.409    1.176  103.8   56.5    95   27.6 
2026-08-31 00:00 UT   17 19 11.1   -21 01 03     0.411    1.174  103.2   56.9    95   27.7 
2026-09-01 00:00 UT   17 20 46.7   -21 04 13     0.413    1.171  102.6   57.2    94   27.7 
2026-09-02 00:00 UT   17 22 25.0   -21 07 22     0.415    1.168  102.0   57.6    94   27.7 
2026-09-03 00:00 UT   17 24 05.9   -21 10 28     0.417    1.166  101.5   58.0    94   27.7 
2026-09-04 00:00 UT   17 25 49.5   -21 13 33     0.419    1.163  100.9   58.4    94   27.7 
2026-09-05 00:00 UT   17 27 35.6   -21 16 35     0.421    1.160  100.3   58.7    94   27.7 
2026-09-06 00:00 UT   17 29 24.2   -21 19 34     0.423    1.158   99.8   59.1    93   27.8 
2026-09-07 00:00 UT   17 31 15.4   -21 22 30     0.425    1.155   99.3   59.5    93   27.8 
2026-09-08 00:00 UT   17 33 09.1   -21 25 23     0.427    1.152   98.7   59.8    93   27.8 

    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.