C/2023 H2 (Lemmon)
ephemeris date magn radius delta ra dec elong phase PA
Perihelion29 Oct 20238.60.894 AU0.500 AU13h31m+50°02'63.9°85.9°349°
Nearest approach10 Nov 20236.60.924 AU0.193 AU18h40m+18°41'64.6°104.6°60°
Today29 Feb 202416.82.173 AU2.800 AU00h25m-44°14'42.3°17.9°142°
C/2023 H2 (Lemmon)- 2024-02-29

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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/2023 H2 (Lemmon) are:

            e (Eccentricity)                : 0.9963440
            q (Perihelion distance)         : 0.8943780
            i (Inclination)                 : 113.75360
            Ω (Longitude of ascending node) : 217.04470
            ω (Argument of perihelion)      : 150.64560
            L (Longitude of perihelion)     : 229.80938
            B (Latitude of perihelion)      : 26.65919
            T (Time of perihelion passage)  : 2460246.68720
            P (Orbital period in years)     : 3826.24

            Epoch                           : 2024 Feb 28
            Reference                       : MPEC 2024-BE0

            Classification(s):              : Nearly isotropic; Returning (a < 10000 AU); External (P > 200 years)

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 (14.00 + 5 log[∆] + 10.00 log[r]), whereas the red curve is being recalculated every 6 hours based on the available COBS/MPC observations (currently 10.68 + 5 log[∆] + 11.63 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.

The following chart shows the short-term path of the comet in a field of view that is optimized for (~10x50) binoculars and finderscopes.
A more printer-friendly version of the same chart can be found further down this page as well.