C/2020 P3 (ATLAS)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Nearest approach	7 Dec 2020	18.4	6.879 AU	6.394 AU	00h47m	+83°01'	115.7°	7.4°	115°
Perihelion	23 Apr 2021	18.6	6.820 AU	7.127 AU	04h06m	+79°15'	68.3°	7.9°	33°
Today	17 Aug 2026	23.1	13.614 AU	14.260 AU	12h56m	+01°06'	48.7°	3.2°	107°

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)                : 1.0039500
    q (Perihelion distance)         : 6.8201750
    i (Inclination)                 : 61.81840
    Ω (Longitude of ascending node) : 19.49340
    ω (Argument of perihelion)      : 82.38870
    L (Longitude of perihelion)     : 93.69442
    B (Latitude of perihelion)      : 60.89020
    T (Time of perihelion passage)  : 2459327.72640

    Epoch                           : 2026 Aug 13
    Reference                       : MPC194169

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

Ephemerides

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2026-08-16 00:00 UT   12 56 14.1   +01 09 54    14.236   13.608   50.0    3.3   107   23.1 
2026-08-17 00:00 UT   12 56 24.3   +01 07 23    14.253   13.612   49.1    3.2   107   23.1 
2026-08-17 09:42 UT   12 56 28.4   +01 06 22    14.260   13.614   48.7    3.2   107   23.1 
2026-08-18 00:00 UT   12 56 34.6   +01 04 51    14.270   13.617   48.2    3.2   107   23.1 
2026-08-19 00:00 UT   12 56 45.1   +01 02 19    14.287   13.622   47.3    3.1   107   23.1 
2026-08-20 00:00 UT   12 56 55.8   +00 59 46    14.304   13.626   46.4    3.1   107   23.1 
2026-08-21 00:00 UT   12 57 06.6   +00 57 13    14.320   13.631   45.5    3.0   106   23.1 
2026-08-22 00:00 UT   12 57 17.6   +00 54 39    14.337   13.636   44.6    3.0   106   23.1 
2026-08-23 00:00 UT   12 57 28.8   +00 52 05    14.353   13.640   43.7    2.9   106   23.1 
2026-08-24 00:00 UT   12 57 40.1   +00 49 30    14.369   13.645   42.8    2.9   106   23.1 
2026-08-25 00:00 UT   12 57 51.6   +00 46 55    14.384   13.650   42.0    2.8   106   23.1 
2026-08-26 00:00 UT   12 58 03.2   +00 44 19    14.400   13.654   41.1    2.8   105   23.1 
2026-08-27 00:00 UT   12 58 15.0   +00 41 44    14.415   13.659   40.2    2.7   105   23.1 

    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.