C/2021 X1 (Maury-Attard)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Perihelion	27 May 2023	15.4	3.234 AU	4.080 AU	02h42m	+02°34'	29.3°	8.8°	229°
Nearest approach	25 Sep 2023	14.6	3.432 AU	2.441 AU	00h39m	+06°40'	169.6°	3.0°	235°
Today	8 Aug 2026	23.8	9.977 AU	9.326 AU	18h39m	+20°07'	127.6°	4.6°	131°

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 5.4 + 5 log[∆] + 13.6 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/2021 X1 (Maury-Attard) are:

    e (Eccentricity)                : 1.0009390
    q (Perihelion distance)         : 3.2340140
    i (Inclination)                 : 140.11250
    Ω (Longitude of ascending node) : 10.65850
    ω (Argument of perihelion)      : 334.65450
    L (Longitude of perihelion)     : 30.63214
    B (Latitude of perihelion)      : -15.93325
    T (Time of perihelion passage)  : 2460092.02890

    Epoch                           : 2026 Aug 08
    Reference                       : MPC194178

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

Ephemerides

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2026-08-07 00:00 UT   18 40 22.3   +20 13 25     9.300    9.965  128.6    4.6   133   23.8 
2026-08-08 00:00 UT   18 39 54.4   +20 10 24     9.313    9.971  128.1    4.6   132   23.8 
2026-08-08 23:37 UT   18 39 27.3   +20 07 23     9.326    9.977  127.6    4.6   131   23.8 
2026-08-09 00:00 UT   18 39 26.9   +20 07 20     9.326    9.977  127.6    4.6   131   23.8 
2026-08-10 00:00 UT   18 38 59.7   +20 04 12     9.340    9.984  127.0    4.6   130   23.8 
2026-08-11 00:00 UT   18 38 33.0   +20 01 02     9.354    9.990  126.5    4.7   128   23.8 
2026-08-12 00:00 UT   18 38 06.6   +19 57 49     9.368    9.996  125.9    4.7   127   23.8 
2026-08-13 00:00 UT   18 37 40.6   +19 54 33     9.382   10.003  125.3    4.7   126   23.8 
2026-08-14 00:00 UT   18 37 14.9   +19 51 14     9.396   10.009  124.8    4.8   125   23.8 
2026-08-15 00:00 UT   18 36 49.7   +19 47 53     9.411   10.015  124.2    4.8   124   23.8 
2026-08-16 00:00 UT   18 36 24.9   +19 44 29     9.426   10.022  123.6    4.8   123   23.8 
2026-08-17 00:00 UT   18 36 00.5   +19 41 03     9.441   10.028  123.0    4.9   122   23.8 
2026-08-18 00:00 UT   18 35 36.5   +19 37 34     9.456   10.034  122.3    4.9   121   23.8 

    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.