C/2020 F8 (SWAN) - DISINTEGRATED
ephemeris date magn radius delta ra dec elong phase PA
Disintegration2 May 20205.20.716 AU0.677 AU 00h05m-09°37'45.2°92.6°237°
Nearest approach10 May 20205.50.572 AU0.571 AU 01h12m+17°18'28.0°124.1°265°
Perihelion25 May 20207.30.435 AU0.906 AU 04h15m+46°20'25.4°91.1°
Today27 Jul 2026-18.474 AU18.764 AU 04h31m-24°09'71.9°3.0°238°
C/2020 F8 (SWAN)- 2026-07-27
astro.vanbuitenen.nl


 
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The interactive orbit chart above shows the comet'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.)


Light curve

The light curve chart below shows the estimated development of the comet's magnitude. Blue and black dots are visual and photometric CCD observations from COBS. This lightcurve is being recalculated every 6 hours based on the available COBS/MPC observations (currently 7.8 + 5 log[∆] + 12.2 log[r]). An additional green curve is displayed when an increase in apparent brightness is expected due to forward scattering of sunlight, which occurs when a dust-rich comet is located between the Earth and the Sun. (See Marcus 2007)



Charts

The all-sky chart below shows the path of the comet over the same period as the light curve. The comet's current position is marked yellow.





The following chart shows the short-term path of the comet in a field of view that is optimized for (~10x50) binoculars and finderscopes.




Orbital elements

The orbital elements of C/2020 F8 (SWAN) are:

    e (Eccentricity)                : 0.9997760
    q (Perihelion distance)         : 0.4351460
    i (Inclination)                 : 110.60310
    Ω (Longitude of ascending node) : 259.85970
    ω (Argument of perihelion)      : 68.18590
    L (Longitude of perihelion)     : 218.53886
    B (Latitude of perihelion)      : 60.34435
    T (Time of perihelion passage)  : 2458994.56190
    P (Orbital period in years)     : 85621.03

    Epoch                           : 2026 May 29
    Reference                       : MPC194166

    Classification(s):              : Nearly isotropic; Returning (a < 10000 AU); External (P > 200 years)

Ephemerides

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2026-07-26 00:00 UT   04 31 28.8   -24 05 57    18.774   18.464   70.7    3.0   237   29.5 
2026-07-27 00:00 UT   04 31 36.3   -24 07 45    18.769   18.469   71.3    3.0   238   29.5 
2026-07-27 21:52 UT   04 31 43.0   -24 09 25    18.764   18.474   71.9    3.0   238   29.5 
2026-07-28 00:00 UT   04 31 43.7   -24 09 34    18.764   18.475   71.9    3.0   238   29.5 
2026-07-29 00:00 UT   04 31 50.9   -24 11 25    18.759   18.480   72.6    3.0   239   29.5 
2026-07-30 00:00 UT   04 31 57.8   -24 13 18    18.753   18.486   73.2    3.0   240   29.5 
2026-07-31 00:00 UT   04 32 04.7   -24 15 12    18.748   18.492   73.8    3.0   241   29.5 
2026-08-01 00:00 UT   04 32 11.3   -24 17 07    18.742   18.497   74.5    3.0   241   29.5 
2026-08-02 00:00 UT   04 32 17.7   -24 19 05    18.737   18.503   75.1    3.0   242   29.5 
2026-08-03 00:00 UT   04 32 24.0   -24 21 03    18.731   18.508   75.7    3.0   243   29.5 
2026-08-04 00:00 UT   04 32 30.0   -24 23 03    18.726   18.514   76.4    3.1   243   29.5 
2026-08-05 00:00 UT   04 32 35.9   -24 25 05    18.720   18.519   77.0    3.1   244   29.5 
2026-08-06 00:00 UT   04 32 41.5   -24 27 08    18.714   18.525   77.7    3.1   245   29.5 



    Terminology:
            
    delta:  distance between comet and earth in AU
    radius: distance between comet 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-comet)    
    phase:  phase angle in degrees (angle sun-comet-earth)        
    AU:     Astronomical Unit (mean distance between earth and sun: 149597870.7 km      
    

Orbital elements usually provided by the MPC (Minor Planet Center).
Observations contributed by observers worldwide, via COBS (Comet Observation Database) or 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.