ephemeris date magn radius delta ra dec elong phase PA
Disintegration1 Apr 20208.11.474 AU1.044 AU07h55m+68°35'92.3°42.6°109°
Nearest approach23 May 2020-0.357 AU0.781 AU03h47m+37°54'17.5°121.2°349°
Perihelion31 May 2020-0.253 AU0.869 AU03h38m+20°01'12.7°118.3°259°
Today19 Sep 2021-6.458 AU6.782 AU07h19m+05°10'67.1°8.2°271°
C/2019 Y4 (ATLAS)- 2021-09-19

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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 C/2019 Y4 (ATLAS) are:

            e (eccentricity)                : 0.9992620
            q (perihelion distance)         : 0.2532100
            i (inclination)                 : 45.37220
            Ω (Longitude of ascending node) : 120.57450
            ω (Argument of perihelion)      : 177.43360
            L (Longitude of perihelion)     : 118.77100
            B (Latitude of perihelion)      : 1.82617
            T (Time of perihelion passage)  : 2459000.52350

            Epoch                           : 2021 Aug 17
            Reference                       : MPEC 2021-P47

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

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 (11.80 + 5 log[∆] + 15.00 log[r]), whereas the red curve is being recalculated every 6 hours based on the available COBS/MPC observations (currently 6.37 + 5 log[∆] + 10.00 log[r]). The additional green curve shows the effect of forward scattering, occurring when the comet is between the earth and the sun, for a gas-to-dust light ratio δ90 of 0.50. (See Marcus 2007)