ephemeris date magn radius delta ra dec elong phase PA
Disintegration26 Jul 20187.20.689 AU0.933 AU05h59m+49°46'41.1°75.9°304°
Nearest approach6 Aug 20185.60.383 AU0.759 AU07h55m+25°26'18.7°121.8°295°
Perihelion16 Aug 20183.70.208 AU0.973 AU09h26m+02°38'11.8°95.0°197°
Today22 Sep 2020-9.031 AU9.570 AU12h51m+53°54'54.9°5.2°16°
C/2017 S3 (PANSTARRS)- 2020-09-22

-1 month
-1 week
-1 day
+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.)

The orbital elements of C/2017 S3 (PANSTARRS), as provided by the minor planet center, are:

            e (eccentricity)                : 1.0000520
            q (perihelion distance)         : 0.2082060
            i (inclination)                 : 99.12970
            Ω (Longitude of ascending node) : 171.17550
            ω (Argument of perihelion)      : 255.84130
            L (Longitude of perihelion)     : 139.00711
            B (Latitude of perihelion)      : -73.20376
            T (Time of perihelion passage)  : 2458346.50140
            P (Orbital period in years)     : > 9999.99 
            Epoch                           : 2020 Sep 22

            Family/Group:                   : Nearly isotropic

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 (11.00 + 5 log[∆] + 10.00 log[r]), whereas the red curve is being recalculated every 6 hours based on the available COBS/MPC observations (currently 9.33 + 5 log[∆] + 12.11 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 0.30. (See Marcus 2007)

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.