C/2020 P4-C (SOHO)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Perihelion	6 Aug 2020	6.9	0.087 AU	0.952 AU	09h19m	+18°34'	3.5°	134.0°	54°
Nearest approach	8 Aug 2020	8.6	0.138 AU	0.908 AU	08h53m	+16°25'	5.3°	137.4°	274°
Today	5 Jul 2025	39.0	23.502 AU	24.316 AU	06h11m	-11°08'	35.9°	1.5°	199°

This comet is a sunskirter. Although it may become very bright at perihelion, this will only be for a very short period very close to the sun.

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 P4-C (SOHO) are:

            e (Eccentricity)                : 1.0128670
            q (Perihelion distance)         : 0.0865840
            i (Inclination)                 : 37.45880
            Ω (Longitude of ascending node) : 164.02940
            ω (Argument of perihelion)      : 116.74790
            L (Longitude of perihelion)     : 106.44177
            B (Latitude of perihelion)      : 32.89571
            T (Time of perihelion passage)  : 2459068.30060

            Epoch                           : 2021 Feb 13
            Reference                       : MPEC 2020-QN1

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

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 (-1.60 + 5 log[∆] + 15.00 log[r]), whereas the red curve is being recalculated every 6 hours based on the available COBS/MPC observations (currently 18.38 + 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 0.30. (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.

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
2025-07-05 00:00 UT   06 11 44.7   -11 08 11    24.305   23.488   35.6    1.4   198   39.0 
2025-07-05 23:12 UT   06 11 54.2   -11 08 30    24.316   23.502   35.9    1.5   199   39.0 
2025-07-06 00:00 UT   06 11 54.5   -11 08 30    24.316   23.502   35.9    1.5   199   39.0 
2025-07-07 00:00 UT   06 12 04.3   -11 08 51    24.328   23.516   36.1    1.5   201   39.0 
2025-07-08 00:00 UT   06 12 14.0   -11 09 13    24.339   23.530   36.4    1.5   202   39.0 
2025-07-09 00:00 UT   06 12 23.7   -11 09 37    24.349   23.543   36.6    1.5   204   39.0 
2025-07-10 00:00 UT   06 12 33.3   -11 10 01    24.360   23.557   36.9    1.5   205   39.0 
2025-07-11 00:00 UT   06 12 42.9   -11 10 27    24.370   23.571   37.2    1.5   207   39.0 
2025-07-12 00:00 UT   06 12 52.4   -11 10 54    24.380   23.585   37.6    1.5   208   39.0 
2025-07-13 00:00 UT   06 13 01.9   -11 11 23    24.390   23.598   37.9    1.5   209   39.0 
2025-07-14 00:00 UT   06 13 11.3   -11 11 53    24.400   23.612   38.3    1.5   211   39.0 
2025-07-15 00:00 UT   06 13 20.6   -11 12 23    24.409   23.626   38.7    1.5   212   39.1 

    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.