C/2020 R6 (Rankin)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Nearest approach	15 Apr 2019	18.7	3.429 AU	3.010 AU	08h49m	-67°06'	106.3°	16.3°	76°
Perihelion	6 Sep 2019	18.5	3.139 AU	3.210 AU	08h14m	-64°00'	76.9°	18.2°	222°
Today	3 Jul 2025	28.9	15.530 AU	15.656 AU	00h09m	+43°41'	81.0°	3.7°	247°

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 R6 (Rankin) are:

            e (Eccentricity)                : 0.9892140
            q (Perihelion distance)         : 3.1394270
            i (Inclination)                 : 82.89100
            Ω (Longitude of ascending node) : 12.23520
            ω (Argument of perihelion)      : 271.99790
            L (Longitude of perihelion)     : -62.02300
            B (Latitude of perihelion)      : -82.61698
            T (Time of perihelion passage)  : 2458733.33170
            P (Orbital period in years)     : 4965.75

            Epoch                           : 2025 Jul 02
            Reference                       : MPEC 2021-Y10

            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 light curve is based on the absolute magnitude and slope parameter as calculated from an MPEC, or the latest values provided by the minor planet center. (11.00 + 5 log[∆] + 10.00 log[r]).

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
2025-07-03 00:00 UT   00 09 33.9   +43 41 16    15.658   15.529   80.8    3.7   247   28.9 
2025-07-03 05:18 UT   00 09 33.0   +43 41 54    15.656   15.530   81.0    3.7   247   28.9 
2025-07-04 00:00 UT   00 09 29.5   +43 44 08    15.650   15.534   81.6    3.7   246   28.9 
2025-07-05 00:00 UT   00 09 24.8   +43 46 58    15.643   15.540   82.3    3.7   246   28.9 
2025-07-06 00:00 UT   00 09 19.8   +43 49 47    15.635   15.545   83.0    3.7   245   28.9 
2025-07-07 00:00 UT   00 09 14.5   +43 52 35    15.627   15.551   83.8    3.7   244   28.9 
2025-07-08 00:00 UT   00 09 08.8   +43 55 22    15.620   15.556   84.5    3.7   244   28.9 
2025-07-09 00:00 UT   00 09 02.8   +43 58 07    15.612   15.562   85.3    3.7   243   28.9 
2025-07-10 00:00 UT   00 08 56.5   +44 00 50    15.604   15.567   86.0    3.7   243   28.9 
2025-07-11 00:00 UT   00 08 49.9   +44 03 31    15.597   15.572   86.7    3.7   242   28.9 
2025-07-12 00:00 UT   00 08 42.9   +44 06 12    15.589   15.578   87.5    3.7   241   28.9 
2025-07-13 00:00 UT   00 08 35.6   +44 08 50    15.581   15.583   88.2    3.7   241   28.9 

    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.