C/2020 F8 (SWAN) - DISINTEGRATED
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Disintegration	2 May 2020	5.2	0.736 AU	0.693 AU	00h04m	-12°25'	46.9°	89.7°	235°
Nearest approach	11 May 2020	5.7	0.573 AU	0.564 AU	01h17m	+16°57'	27.6°	125.4°	264°
Perihelion	26 May 2020	7.6	0.432 AU	0.908 AU	04h22m	+46°17'	25.2°	91.1°	5°
Today	1 Jun 2025	-	16.040 AU	16.753 AU	04h22m	-21°56'	44.1°	2.5°	184°

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.)

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

            e (Eccentricity)                : 0.9998270
            q (Perihelion distance)         : 0.4317580
            i (Inclination)                 : 110.54740
            Ω (Longitude of ascending node) : 259.78910
            ω (Argument of perihelion)      : 68.09680
            L (Longitude of perihelion)     : 218.66961
            B (Latitude of perihelion)      : 60.31831
            T (Time of perihelion passage)  : 2458995.66650
            P (Orbital period in years)     : 124678.46

            Epoch                           : 2025 Feb 02
            Reference                       : MPEC 2025-AE4

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

The light curve chart below shows the estimated development of the comet's magnitude. Blue and black dots are visual and photometric CCD observations respectively from COBS or the MPC. The gray curve is based on the absolute magnitude and slope parameter as calculated from the original MPEC, or the latest values provided by the MPC (10.00 + 5 log[∆] + 10.00 log[r]), whereas the red curve is being recalculated every 6 hours based on the available COBS/MPC observations (currently 7.69 + 5 log[∆] + 12.34 log[r]). The additional green curve shows the effect of forward scattering, occurring when the comet is between the earth and the sun, for a gas-to-dust light ratio δ90 of 0.30. (See Marcus 2007)

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.
A more printer-friendly version of the same chart can be found further down this page as well.

The following chart shows the current location of the comet in a smaller, upside-down telescopic field of view.

A printable version of the short-term path of the comet in a field of view that is optimized for (~10x50) binoculars and finderscopes.

Ephemerides:

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2025-06-01 00:00 UT   04 22 50.0   -21 56 14    16.752   16.040   44.0    2.5   184   28.7 
2025-06-01 01:47 UT   04 22 51.1   -21 56 14    16.753   16.040   44.1    2.5   184   28.7 
2025-06-02 00:00 UT   04 23 04.5   -21 56 11    16.756   16.046   44.3    2.5   185   28.7 
2025-06-03 00:00 UT   04 23 19.0   -21 56 11    16.759   16.052   44.5    2.5   187   28.7 
2025-06-04 00:00 UT   04 23 33.5   -21 56 13    16.762   16.058   44.7    2.5   188   28.7 
2025-06-05 00:00 UT   04 23 47.9   -21 56 18    16.765   16.064   45.0    2.6   189   28.7 
2025-06-06 00:00 UT   04 24 02.3   -21 56 25    16.768   16.070   45.2    2.6   190   28.7 
2025-06-07 00:00 UT   04 24 16.7   -21 56 34    16.770   16.076   45.5    2.6   192   28.7 
2025-06-08 00:00 UT   04 24 31.0   -21 56 46    16.772   16.082   45.8    2.6   193   28.7 
2025-06-09 00:00 UT   04 24 45.3   -21 57 00    16.774   16.088   46.1    2.6   194   28.7 
2025-06-10 00:00 UT   04 24 59.6   -21 57 17    16.776   16.093   46.4    2.6   195   28.7 
2025-06-11 00:00 UT   04 25 13.8   -21 57 36    16.778   16.099   46.7    2.6   196   28.7 

    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.