C/2020 F5 (MASTER)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Perihelion	15 Mar 2021	15.2	4.325 AU	4.994 AU	22h37m	-42°42'	43.3°	9.1°	204°
Nearest approach	22 Aug 2021	14.7	4.514 AU	3.586 AU	23h13m	-32°48'	153.6°	5.7°	319°
Today	2 Nov 2025	21.3	12.519 AU	11.814 AU	00h36m	+55°45'	133.6°	3.3°	140°

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 5.9 + 5 log[∆] + 9.2 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 F5 (MASTER) are:

    e (Eccentricity)                : 0.9734600
    q (Perihelion distance)         : 4.3253580
    i (Inclination)                 : 52.23880
    Ω (Longitude of ascending node) : 350.55530
    ω (Argument of perihelion)      : 310.59240
    L (Longitude of perihelion)     : 315.00349
    B (Latitude of perihelion)      : -36.89320
    T (Time of perihelion passage)  : 2459289.48650
    P (Orbital period in years)     : 2080.57

    Epoch                           : 2025 Nov 01
    Reference                       : MPEC 2024-UQ8

    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
2025-11-01 00:00 UT   00 37 07.0   +55 48 59    11.803   12.510  133.7    3.3   143   21.3 
2025-11-02 00:00 UT   00 36 41.9   +55 46 58    11.810   12.515  133.6    3.3   141   21.3 
2025-11-02 15:34 UT   00 36 25.8   +55 45 37    11.814   12.519  133.6    3.3   140   21.3 
2025-11-03 00:00 UT   00 36 17.1   +55 44 53    11.816   12.521  133.6    3.3   140   21.3 
2025-11-04 00:00 UT   00 35 52.7   +55 42 46    11.823   12.526  133.5    3.3   138   21.3 
2025-11-05 00:00 UT   00 35 28.6   +55 40 35    11.830   12.532  133.4    3.3   137   21.3 
2025-11-06 00:00 UT   00 35 05.0   +55 38 22    11.837   12.537  133.2    3.3   135   21.3 
2025-11-07 00:00 UT   00 34 41.7   +55 36 06    11.844   12.542  133.1    3.3   134   21.4 
2025-11-08 00:00 UT   00 34 18.8   +55 33 47    11.852   12.548  132.9    3.3   132   21.4 
2025-11-09 00:00 UT   00 33 56.4   +55 31 26    11.859   12.553  132.8    3.3   131   21.4 
2025-11-10 00:00 UT   00 33 34.3   +55 29 01    11.867   12.559  132.6    3.3   129   21.4 
2025-11-11 00:00 UT   00 33 12.7   +55 26 35    11.875   12.564  132.3    3.3   128   21.4 
2025-11-12 00:00 UT   00 32 51.5   +55 24 06    11.884   12.569  132.1    3.3   126   21.4 

    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.