Skip Navigation Links

C/2021 G3 (PANSTARRS)
ephemeris date magn radius delta ra dec elong phase PA
Perihelion18 Oct 202121.45.188 AU5.747 AU 10h36m+18°52'51.6°8.7°300°
Nearest approach5 Feb 202220.95.254 AU4.368 AU 10h28m+39°48'151.3°5.2°219°
Today9 Jul 202627.012.659 AU12.556 AU 21h26m+59°50'93.5°4.6°210°
C/2021 G3 (PANSTARRS)- 2026-07-09
astro.vanbuitenen.nl


 
-1 month
-1 week
-1 day
Now
+1 day
+1 week
+1 month

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. (10.5 + 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 G3 (PANSTARRS) are: 

    e (Eccentricity)                : 0.9997800
    q (Perihelion distance)         : 5.1876580
    i (Inclination)                 : 102.88060
    Ω (Longitude of ascending node) : 147.31820
    ω (Argument of perihelion)      : 10.65400
    L (Longitude of perihelion)     : 144.91686
    B (Latitude of perihelion)      : 10.38290
    T (Time of perihelion passage)  : 2459505.61100

    Epoch                           : 2026 Jul 09
    Reference                       : MPC194174

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

Ephemerides

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2026-07-08 00:00 UT   21 27 37.1   +59 49 27    12.559   12.650   92.8    4.6   212   27.0 
2026-07-09 00:00 UT   21 27 08.9   +59 50 19    12.557   12.655   93.2    4.6   211   27.0 
2026-07-09 18:23 UT   21 26 47.0   +59 50 56    12.556   12.659   93.5    4.6   210   27.0 
2026-07-10 00:00 UT   21 26 40.3   +59 51 06    12.556   12.660   93.6    4.6   210   27.0 
2026-07-11 00:00 UT   21 26 11.4   +59 51 49    12.554   12.666   94.0    4.6   209   27.0 
2026-07-12 00:00 UT   21 25 42.1   +59 52 28    12.552   12.671   94.4    4.6   208   27.0 
2026-07-13 00:00 UT   21 25 12.5   +59 53 02    12.551   12.676   94.8    4.6   207   27.0 
2026-07-14 00:00 UT   21 24 42.7   +59 53 32    12.549   12.681   95.2    4.6   206   27.0 
2026-07-15 00:00 UT   21 24 12.5   +59 53 56    12.548   12.687   95.5    4.6   205   27.0 
2026-07-16 00:00 UT   21 23 42.0   +59 54 16    12.546   12.692   95.9    4.6   204   27.0 
2026-07-17 00:00 UT   21 23 11.2   +59 54 32    12.545   12.697   96.3    4.6   203   27.0 
2026-07-18 00:00 UT   21 22 40.2   +59 54 42    12.543   12.702   96.7    4.6   202   27.0 
2026-07-19 00:00 UT   21 22 09.0   +59 54 48    12.542   12.708   97.1    4.6   201   27.0 




    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.

Privacy policy