C/2020 P4-C (SOHO)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Perihelion	5 Aug 2020	7.0	0.089 AU	0.949 AU	09h13m	+19°08'	3.6°	135.0°	52°
Nearest approach	7 Aug 2020	8.6	0.136 AU	0.909 AU	08h47m	+17°11'	5.1°	138.1°	278°
Today	11 May 2026	40.1	27.744 AU	28.352 AU	06h05m	-11°32'	52.0°	1.6°	124°

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.)

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. This lightcurve is being recalculated every 6 hours based on the available COBS/MPC observations (currently 18.4 + 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 P4-C (SOHO) are:

    e (Eccentricity)                : 1.0132280
    q (Perihelion distance)         : 0.0893440
    i (Inclination)                 : 37.24160
    Ω (Longitude of ascending node) : 165.45210
    ω (Argument of perihelion)      : 115.82340
    L (Longitude of perihelion)     : 106.74643
    B (Latitude of perihelion)      : 33.00723
    T (Time of perihelion passage)  : 2459066.74730

    Epoch                           : 2026 May 10
    Reference                       : MPEC 2020-QN1

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

Ephemerides

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2026-05-10 00:00 UT   06 05 42.0   -11 34 06    28.316   27.722   53.0    1.7   123   40.1 
2026-05-11 00:00 UT   06 05 48.6   -11 33 20    28.339   27.736   52.3    1.7   123   40.1 
2026-05-11 13:37 UT   06 05 52.4   -11 32 54    28.352   27.744   52.0    1.6   124   40.1 
2026-05-12 00:00 UT   06 05 55.3   -11 32 34    28.363   27.750   51.7    1.6   124   40.1 
2026-05-13 00:00 UT   06 06 02.0   -11 31 50    28.386   27.764   51.0    1.6   125   40.1 
2026-05-14 00:00 UT   06 06 08.9   -11 31 07    28.409   27.778   50.4    1.6   126   40.1 
2026-05-15 00:00 UT   06 06 15.8   -11 30 24    28.431   27.792   49.8    1.6   127   40.1 
2026-05-16 00:00 UT   06 06 22.8   -11 29 43    28.454   27.806   49.2    1.6   128   40.1 
2026-05-17 00:00 UT   06 06 29.9   -11 29 03    28.476   27.820   48.6    1.6   129   40.1 
2026-05-18 00:00 UT   06 06 37.0   -11 28 23    28.499   27.834   48.0    1.5   130   40.1 
2026-05-19 00:00 UT   06 06 44.3   -11 27 45    28.521   27.848   47.4    1.5   131   40.1 
2026-05-20 00:00 UT   06 06 51.6   -11 27 08    28.543   27.862   46.8    1.5   132   40.1 
2026-05-21 00:00 UT   06 06 58.9   -11 26 32    28.564   27.876   46.2    1.5   133   40.1 

    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.