C/2020 H3 (Wierzchos)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Perihelion	31 May 2020	17.8	2.306 AU	1.700 AU	20h12m	+17°21'	114.0°	23.7°	235°
Nearest approach	20 Jun 2020	17.7	2.317 AU	1.638 AU	19h54m	+30°03'	119.7°	22.4°	211°
Today	17 Jul 2026	31.5	16.823 AU	17.688 AU	05h39m	+35°04'	30.8°	1.8°	288°

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. (13.0 + 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/2020 H3 (Wierzchos) are:

    e (Eccentricity)                : 1.0002450
    q (Perihelion distance)         : 2.3060730
    i (Inclination)                 : 62.27800
    Ω (Longitude of ascending node) : 270.63560
    ω (Argument of perihelion)      : 29.52160
    L (Longitude of perihelion)     : 285.39315
    B (Latitude of perihelion)      : 25.86111
    T (Time of perihelion passage)  : 2459001.40860

    Epoch                           : 2026 May 29
    Reference                       : MPC194166

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

Ephemerides

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2026-07-16 00:00 UT   05 39 16.5   +35 04 44    17.691   16.816   29.7    1.7   289   31.5 
2026-07-17 00:00 UT   05 39 31.5   +35 04 48    17.689   16.821   30.5    1.8   289   31.5 
2026-07-17 08:32 UT   05 39 36.8   +35 04 49    17.688   16.823   30.8    1.8   288   31.5 
2026-07-18 00:00 UT   05 39 46.4   +35 04 52    17.686   16.827   31.3    1.8   288   31.5 
2026-07-19 00:00 UT   05 40 01.1   +35 04 57    17.683   16.833   32.2    1.8   287   31.5 
2026-07-20 00:00 UT   05 40 15.7   +35 05 02    17.681   16.838   33.0    1.9   287   31.5 
2026-07-21 00:00 UT   05 40 30.2   +35 05 07    17.677   16.844   33.8    1.9   286   31.5 
2026-07-22 00:00 UT   05 40 44.6   +35 05 13    17.674   16.849   34.7    2.0   285   31.5 
2026-07-23 00:00 UT   05 40 58.8   +35 05 19    17.670   16.855   35.5    2.0   285   31.5 
2026-07-24 00:00 UT   05 41 12.8   +35 05 26    17.666   16.860   36.4    2.0   284   31.5 
2026-07-25 00:00 UT   05 41 26.7   +35 05 33    17.662   16.866   37.2    2.1   284   31.5 
2026-07-26 00:00 UT   05 41 40.5   +35 05 40    17.658   16.871   38.1    2.1   283   31.5 
2026-07-27 00:00 UT   05 41 54.1   +35 05 48    17.654   16.877   39.0    2.2   283   31.5 

    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.