C/2020 H8 (PANSTARRS)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Perihelion	4 Jun 2020	20.2	4.662 AU	4.091 AU	17h43m	+37°44'	118.5°	11.0°	194°
Nearest approach	18 Jun 2020	20.2	4.663 AU	4.067 AU	17h23m	+35°59'	120.3°	10.8°	173°
Today	19 Sep 2025	27.7	13.830 AU	14.160 AU	12h36m	-66°42'	68.9°	3.9°	166°

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/2020 H8 (PANSTARRS) are:

            e (Eccentricity)                : 0.9920730
            q (Perihelion distance)         : 4.6618430
            i (Inclination)                 : 99.70110
            Ω (Longitude of ascending node) : 68.43570
            ω (Argument of perihelion)      : 128.80400
            L (Longitude of perihelion)     : 80.27090
            B (Latitude of perihelion)      : 50.18809
            T (Time of perihelion passage)  : 2459005.34150
            P (Orbital period in years)     : 14261.76

            Epoch                           : 2025 Sep 18
            Reference                       : MPEC 2021-N06

            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 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. (10.50 + 5 log[∆] + 10.00 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.

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.

The following chart shows the current location of the comet in a smaller, upside-down telescopic field of view.

A printable version of the short-term path of the comet in a field of view that is optimized for (~10x50) binoculars and finderscopes.

Ephemerides:

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2025-09-19 00:00 UT   12 36 38.4   -66 42 50    14.159   13.830   68.9    3.9   166   27.7 
2025-09-19 02:58 UT   12 36 42.0   -66 42 52    14.160   13.830   68.9    3.9   166   27.7 
2025-09-20 00:00 UT   12 37 07.8   -66 43 12    14.171   13.835   68.5    3.9   167   27.7 
2025-09-21 00:00 UT   12 37 37.4   -66 43 39    14.184   13.840   68.0    3.9   168   27.7 
2025-09-22 00:00 UT   12 38 07.1   -66 44 08    14.197   13.846   67.6    3.8   169   27.7 
2025-09-23 00:00 UT   12 38 36.9   -66 44 42    14.209   13.851   67.2    3.8   169   27.7 
2025-09-24 00:00 UT   12 39 06.7   -66 45 18    14.222   13.856   66.7    3.8   170   27.7 
2025-09-25 00:00 UT   12 39 36.7   -66 45 58    14.234   13.861   66.3    3.8   171   27.7 
2025-09-26 00:00 UT   12 40 06.8   -66 46 42    14.246   13.867   65.9    3.8   172   27.7 
2025-09-27 00:00 UT   12 40 36.9   -66 47 29    14.258   13.872   65.5    3.8   173   27.7 
2025-09-28 00:00 UT   12 41 07.1   -66 48 19    14.270   13.877   65.0    3.8   173   27.7 
2025-09-29 00:00 UT   12 41 37.3   -66 49 13    14.282   13.883   64.6    3.7   174   27.7 

    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.