C/2020 P3 (ATLAS)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Nearest approach	7 Dec 2020	18.4	6.876 AU	6.391 AU	00h47m	+83°00'	115.7°	7.4°	114°
Perihelion	23 Apr 2021	18.6	6.817 AU	7.123 AU	04h05m	+79°15'	68.4°	7.9°	32°
Today	8 Nov 2025	22.5	12.300 AU	13.122 AU	13h13m	+04°37'	32.7°	2.5°	311°

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. 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. (6.0 + 5 log[∆] + 10.0 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 P3 (ATLAS) are:

    e (Eccentricity)                : 1.0038730
    q (Perihelion distance)         : 6.8171830
    i (Inclination)                 : 61.84420
    Ω (Longitude of ascending node) : 19.48770
    ω (Argument of perihelion)      : 82.36290
    L (Longitude of perihelion)     : 93.62458
    B (Latitude of perihelion)      : 60.90882
    T (Time of perihelion passage)  : 2459327.61910

    Epoch                           : 2025 Nov 07
    Reference                       : MPEC 2024-JU4

    Classification(s):              : Nearly isotropic; New (a > 10000 AU)

Ephemerides

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2025-11-07 00:00 UT   13 13 21.5   +04 41 27    13.128   12.293   31.4    2.4   312   22.5 
2025-11-08 00:00 UT   13 13 37.1   +04 39 03    13.124   12.297   32.2    2.5   311   22.5 
2025-11-08 13:22 UT   13 13 45.7   +04 37 44    13.122   12.300   32.7    2.5   311   22.5 
2025-11-09 00:00 UT   13 13 52.6   +04 36 41    13.120   12.302   33.1    2.5   311   22.5 
2025-11-10 00:00 UT   13 14 07.9   +04 34 21    13.116   12.307   33.9    2.6   310   22.5 
2025-11-11 00:00 UT   13 14 23.1   +04 32 02    13.111   12.311   34.8    2.6   310   22.5 
2025-11-12 00:00 UT   13 14 38.2   +04 29 45    13.106   12.316   35.7    2.7   309   22.5 
2025-11-13 00:00 UT   13 14 53.2   +04 27 29    13.101   12.321   36.6    2.7   308   22.5 
2025-11-14 00:00 UT   13 15 08.0   +04 25 15    13.096   12.325   37.4    2.8   308   22.5 
2025-11-15 00:00 UT   13 15 22.7   +04 23 03    13.091   12.330   38.3    2.9   307   22.5 
2025-11-16 00:00 UT   13 15 37.2   +04 20 52    13.085   12.335   39.2    2.9   307   22.5 
2025-11-17 00:00 UT   13 15 51.6   +04 18 43    13.079   12.339   40.1    3.0   306   22.5 
2025-11-18 00:00 UT   13 16 05.8   +04 16 36    13.073   12.344   41.0    3.0   306   22.5 

    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.