C/2021 N3 (PANSTARRS)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Nearest approach	4 Jul 2020	19.5	5.718 AU	4.798 AU	18h56m	-50°34'	152.3°	4.7°	359°
Perihelion	16 Aug 2020	19.6	5.710 AU	5.024 AU	18h39m	-48°07'	128.5°	8.0°	64°
Today	1 Nov 2025	25.2	13.231 AU	12.358 AU	00h28m	+24°20'	150.5°	2.1°	104°

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. (8.5 + 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/2021 N3 (PANSTARRS) are:

    e (Eccentricity)                : 0.9589790
    q (Perihelion distance)         : 5.7097920
    i (Inclination)                 : 26.76800
    Ω (Longitude of ascending node) : 337.53530
    ω (Argument of perihelion)      : 304.55770
    L (Longitude of perihelion)     : 285.18310
    B (Latitude of perihelion)      : -21.77187
    T (Time of perihelion passage)  : 2459078.02320
    P (Orbital period in years)     : 1642.18

    Epoch                           : 2025 Oct 31
    Reference                       : MPEC 2022-YB4

    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
2025-10-31 00:00 UT   00 28 24.2   +24 23 14    12.341   13.223  151.7    2.0   106   25.2 
2025-11-01 00:00 UT   00 28 11.4   +24 21 39    12.352   13.228  150.9    2.1   105   25.2 
2025-11-01 12:36 UT   00 28 04.8   +24 20 49    12.358   13.231  150.5    2.1   104   25.2 
2025-11-02 00:00 UT   00 27 58.9   +24 20 04    12.363   13.233  150.1    2.1   103   25.2 
2025-11-03 00:00 UT   00 27 46.6   +24 18 28    12.375   13.238  149.3    2.2   102   25.2 
2025-11-04 00:00 UT   00 27 34.5   +24 16 52    12.387   13.243  148.5    2.2   101   25.2 
2025-11-05 00:00 UT   00 27 22.7   +24 15 16    12.399   13.248  147.7    2.3    99   25.2 
2025-11-06 00:00 UT   00 27 11.0   +24 13 40    12.411   13.253  146.9    2.3    98   25.2 
2025-11-07 00:00 UT   00 26 59.6   +24 12 03    12.424   13.258  146.0    2.4    97   25.2 
2025-11-08 00:00 UT   00 26 48.4   +24 10 26    12.436   13.262  145.2    2.4    96   25.2 
2025-11-09 00:00 UT   00 26 37.4   +24 08 48    12.450   13.267  144.3    2.5    95   25.2 
2025-11-10 00:00 UT   00 26 26.7   +24 07 11    12.463   13.272  143.5    2.5    94   25.2 
2025-11-11 00:00 UT   00 26 16.2   +24 05 34    12.476   13.277  142.6    2.6    93   25.2 

    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.