A/2020 M4
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Perihelion	22 Nov 2020	22.1	5.941 AU	6.880 AU	16h15m	-04°29'	16.7°	2.7°	18°
Nearest approach	4 May 2021	21.6	6.051 AU	5.097 AU	15h23m	+02°37'	159.3°	3.4°	205°
Today	29 Jun 2025	25.2	12.340 AU	12.940 AU	09h57m	+06°45'	52.0°	3.7°	114°

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 A/2020 M4 are:

            e (Eccentricity)                : 0.9997650
            q (Perihelion distance)         : 5.9409000
            i (Inclination)                 : 160.10270
            Ω (Longitude of ascending node) : 348.61460
            ω (Argument of perihelion)      : 104.48160
            L (Longitude of perihelion)     : 63.25584
            B (Latitude of perihelion)      : 19.23977
            T (Time of perihelion passage)  : 2459176.29780

            Epoch                           : 2025 Jun 28
            Reference                       : MPEC 2023-N01

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

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 indicates the expected brightness if this object is a comet (14.50 + 5 log[∆] + 5.00 log[r]), whereas the red curve indicates the expected lightcurve for an asteroid (H=13.80; G=.15).

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
2025-06-29 00:00 UT   09 57 49.9   +06 45 19    12.936   12.339   52.2    3.7   114   25.2 
2025-06-29 05:24 UT   09 57 51.3   +06 45 10    12.940   12.340   52.0    3.7   114   25.2 
2025-06-30 00:00 UT   09 57 56.1   +06 44 39    12.954   12.344   51.3    3.7   114   25.2 
2025-07-01 00:00 UT   09 58 02.5   +06 43 59    12.972   12.349   50.4    3.6   115   25.2 
2025-07-02 00:00 UT   09 58 09.1   +06 43 16    12.990   12.354   49.5    3.6   115   25.2 
2025-07-03 00:00 UT   09 58 15.8   +06 42 33    13.008   12.359   48.5    3.5   115   25.2 
2025-07-04 00:00 UT   09 58 22.8   +06 41 48    13.026   12.364   47.6    3.5   115   25.2 
2025-07-05 00:00 UT   09 58 30.0   +06 41 02    13.044   12.369   46.7    3.4   115   25.2 
2025-07-06 00:00 UT   09 58 37.3   +06 40 14    13.061   12.374   45.8    3.4   115   25.2 
2025-07-07 00:00 UT   09 58 44.8   +06 39 25    13.078   12.379   44.9    3.3   116   25.2 
2025-07-08 00:00 UT   09 58 52.4   +06 38 36    13.095   12.384   44.0    3.3   116   25.2 
2025-07-09 00:00 UT   09 59 00.3   +06 37 44    13.112   12.389   43.1    3.2   116   25.2 

    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.