C/2021 J1 (Maury-Attard)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Perihelion	19 Feb 2021	19.7	1.735 AU	2.325 AU	19h27m	+02°10'	42.8°	22.8°	289°
Nearest approach	27 May 2021	19.3	2.113 AU	1.302 AU	19h34m	-52°29'	131.3°	21.1°	290°
Today	18 Mar 2025	31.7	11.988 AU	11.979 AU	05h43m	-48°55'	88.1°	4.8°	91°

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)                : 0.9338310
            q (Perihelion distance)         : 1.7349770
            i (Inclination)                 : 92.70760
            Ω (Longitude of ascending node) : 88.43260
            ω (Argument of perihelion)      : 147.21640
            L (Longitude of perihelion)     : 90.17525
            B (Latitude of perihelion)      : 32.74241
            T (Time of perihelion passage)  : 2459264.91730
            P (Orbital period in years)     : 134.26

            Epoch                           : 2025 Mar 16
            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
2025-03-18 00:00 UT   05 43 49.8   -48 57 27    11.976   11.986   88.2    4.8    90   31.7 
2025-03-18 08:07 UT   05 43 50.2   -48 55 36    11.979   11.988   88.1    4.8    91   31.7 
2025-03-19 00:00 UT   05 43 51.0   -48 51 58    11.987   11.991   87.9    4.8    91   31.7 
2025-03-20 00:00 UT   05 43 52.7   -48 46 31    11.997   11.997   87.6    4.8    92   31.7 
2025-03-21 00:00 UT   05 43 54.9   -48 41 04    12.008   12.002   87.3    4.8    93   31.7 
2025-03-22 00:00 UT   05 43 57.5   -48 35 38    12.019   12.008   87.0    4.8    94   31.7 
2025-03-23 00:00 UT   05 44 00.7   -48 30 12    12.030   12.014   86.7    4.8    95   31.7 
2025-03-24 00:00 UT   05 44 04.4   -48 24 48    12.041   12.019   86.4    4.7    96   31.7 
2025-03-25 00:00 UT   05 44 08.5   -48 19 25    12.052   12.025   86.0    4.7    97   31.7 
2025-03-26 00:00 UT   05 44 13.2   -48 14 03    12.063   12.030   85.7    4.7    98   31.7 
2025-03-27 00:00 UT   05 44 18.3   -48 08 42    12.074   12.036   85.4    4.7    99   31.7 
2025-03-28 00:00 UT   05 44 23.9   -48 03 23    12.085   12.041   85.1    4.7   100   31.7 

    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.