ephemeris date magn radius delta ra dec elong phase PA
Perihelion10 Sep 20187.41.011 AU0.386 AU05h51m+33°22'79.5°78.4°271°
Nearest approach10 Sep 20187.41.011 AU0.386 AU05h52m+32°52'79.5°78.4°271°
Today25 Feb 202126.65.722 AU4.843 AU11h58m-12°07'150.0°5.0°314°
21P/Giacobini-Zinner- 2021-02-25

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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 21P/Giacobini-Zinner, as provided by the minor planet center, are:

            e (eccentricity)                : 0.7108390
            q (perihelion distance)         : 1.0108400
            i (inclination)                 : 32.02630
            Ω (Longitude of ascending node) : 195.35450
            ω (Argument of perihelion)      : 172.85160
            L (Longitude of perihelion)     : 189.28521
            B (Latitude of perihelion)      : 3.78378
            T (Time of perihelion passage)  : 2458372.05490
            P (Orbital period in years)     : 6.54

            Epoch                           : 2021 Feb 24
            Reference                       : MPC111773

            Classification(s):              : Ecliptic; Jupiter family
            Tisserand (Jupiter)             : 2.466

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 gray curve is based on the absolute magnitude and slope parameter as calculated from the original MPEC, or the latest values provided by the MPC (9.00 + 5 log[∆] + 15.00 log[r]), whereas the red curve is being recalculated every 6 hours based on the available COBS/MPC observations (currently 9.39 + 5 log[∆] + 18.26 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.