2021 SF1
ephemeris	date	magn	radius	delta	ra	dec	elong	phase
Today	11 Jul 2026	26.2	1.293 AU	0.303 AU	17h21m	-19°50'	152.4°	21.3°

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 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
2026-07-11 00:00 UT   17 21 41.4   -19 50 21     0.303    1.293  152.4   21.3   100   26.2 
2026-07-11 17:35 UT   17 20 15.4   -19 49 18     0.304    1.292  151.4   22.1   100   26.2 
2026-07-12 00:00 UT   17 19 44.5   -19 48 56     0.304    1.291  151.0   22.4   100   26.2 
2026-07-13 00:00 UT   17 17 51.8   -19 47 35     0.305    1.289  149.6   23.5   100   26.3 
2026-07-14 00:00 UT   17 16 03.4   -19 46 20     0.307    1.287  148.3   24.5   100   26.3 
2026-07-15 00:00 UT   17 14 19.5   -19 45 10     0.308    1.285  146.9   25.6   100   26.3 
2026-07-16 00:00 UT   17 12 40.2   -19 44 06     0.309    1.283  145.6   26.6    99   26.4 
2026-07-17 00:00 UT   17 11 05.7   -19 43 08     0.311    1.281  144.3   27.6    99   26.4 
2026-07-18 00:00 UT   17 09 36.1   -19 42 17     0.312    1.279  143.0   28.6    99   26.5 
2026-07-19 00:00 UT   17 08 11.4   -19 41 33     0.314    1.277  141.7   29.6    99   26.5 
2026-07-20 00:00 UT   17 06 51.8   -19 40 57     0.315    1.275  140.4   30.5    99   26.5 
2026-07-21 00:00 UT   17 05 37.1   -19 40 28     0.317    1.273  139.2   31.4    99   26.6 
2026-07-22 00:00 UT   17 04 27.6   -19 40 07     0.319    1.271  138.0   32.4    99   26.6 
2026-07-23 00:00 UT   17 03 23.1   -19 39 54     0.321    1.269  136.8   33.3    99   26.6 
2026-07-24 00:00 UT   17 02 23.7   -19 39 49     0.323    1.267  135.6   34.1    99   26.7 
2026-07-25 00:00 UT   17 01 29.4   -19 39 53     0.325    1.265  134.4   35.0    99   26.7 
2026-07-26 00:00 UT   17 00 40.1   -19 40 05     0.327    1.262  133.3   35.9    99   26.7 
2026-07-27 00:00 UT   16 59 55.8   -19 40 25     0.329    1.260  132.1   36.7    99   26.8 
2026-07-28 00:00 UT   16 59 16.4   -19 40 54     0.331    1.258  131.0   37.5    99   26.8 
2026-07-29 00:00 UT   16 58 42.0   -19 41 31     0.333    1.256  130.0   38.3    99   26.8 
2026-07-30 00:00 UT   16 58 12.5   -19 42 17     0.336    1.254  128.9   39.1    98   26.9 
2026-07-31 00:00 UT   16 57 47.8   -19 43 12     0.338    1.251  127.8   39.8    98   26.9 
2026-08-01 00:00 UT   16 57 27.8   -19 44 14     0.340    1.249  126.8   40.6    98   26.9 
2026-08-02 00:00 UT   16 57 12.5   -19 45 25     0.343    1.247  125.8   41.3    98   27.0 
2026-08-03 00:00 UT   16 57 01.9   -19 46 44     0.345    1.244  124.8   42.0    98   27.0 
2026-08-04 00:00 UT   16 56 55.8   -19 48 11     0.347    1.242  123.8   42.7    98   27.0 
2026-08-05 00:00 UT   16 56 54.3   -19 49 46     0.350    1.240  122.9   43.4    98   27.1 
2026-08-06 00:00 UT   16 56 57.2   -19 51 29     0.352    1.237  121.9   44.1    98   27.1 
2026-08-07 00:00 UT   16 57 04.5   -19 53 19     0.355    1.235  121.0   44.7    98   27.1 
2026-08-08 00:00 UT   16 57 16.1   -19 55 16     0.357    1.232  120.1   45.4    98   27.1 
2026-08-09 00:00 UT   16 57 32.0   -19 57 20     0.360    1.230  119.2   46.0    98   27.2 
2026-08-10 00:00 UT   16 57 52.2   -19 59 31     0.362    1.228  118.3   46.6    98   27.2 

    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.