C/2021 J1 (Maury-Attard)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Perihelion	19 Feb 2021	19.7	1.734 AU	2.324 AU	19h27m	+02°11'	42.8°	22.8°	289°
Nearest approach	27 May 2021	19.3	2.112 AU	1.301 AU	19h34m	-52°30'	131.3°	21.1°	290°
Today	22 Jun 2025	32.0	12.516 AU	12.881 AU	06h11m	-43°20'	66.8°	4.3°	178°

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/2021 J1 (Maury-Attard) are:

            e (Eccentricity)                : 0.9338140
            q (Perihelion distance)         : 1.7339630
            i (Inclination)                 : 92.70770
            Ω (Longitude of ascending node) : 88.43210
            ω (Argument of perihelion)      : 147.19920
            L (Longitude of perihelion)     : 90.17596
            B (Latitude of perihelion)      : 32.75958
            T (Time of perihelion passage)  : 2459264.92400
            P (Orbital period in years)     : 134.09

            Epoch                           : 2025 Jun 21
            Reference                       : MPEC 2022-C56

            Classification(s):              : Nearly isotropic; Returning (a < 10000 AU); Halley type (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. (15.50 + 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
2025-06-22 00:00 UT   06 11 12.1   -43 20 28    12.880   12.515   66.8    4.3   178   32.0 
2025-06-22 05:55 UT   06 11 18.2   -43 20 18    12.881   12.516   66.8    4.3   178   32.0 
2025-06-23 00:00 UT   06 11 36.7   -43 19 48    12.886   12.520   66.8    4.3   179   32.0 
2025-06-24 00:00 UT   06 12 01.2   -43 19 13    12.892   12.526   66.7    4.3   180   32.0 
2025-06-25 00:00 UT   06 12 25.7   -43 18 41    12.898   12.531   66.7    4.3   181   32.0 
2025-06-26 00:00 UT   06 12 50.2   -43 18 13    12.904   12.537   66.7    4.3   181   32.0 
2025-06-27 00:00 UT   06 13 14.7   -43 17 50    12.910   12.542   66.7    4.3   182   32.0 
2025-06-28 00:00 UT   06 13 39.1   -43 17 30    12.915   12.548   66.7    4.3   183   32.0 
2025-06-29 00:00 UT   06 14 03.4   -43 17 14    12.921   12.553   66.6    4.3   184   32.0 
2025-06-30 00:00 UT   06 14 27.7   -43 17 02    12.926   12.559   66.6    4.3   185   32.0 
2025-07-01 00:00 UT   06 14 51.9   -43 16 54    12.932   12.564   66.6    4.3   186   32.0 
2025-07-02 00:00 UT   06 15 16.1   -43 16 49    12.937   12.569   66.7    4.3   187   32.1 

    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.