C/2019 L3 (ATLAS)
ephemeris date magn radius delta ra dec elong phase PA
Nearest approach6 Jan 20229.43.560 AU2.586 AU07h06m+31°48'170.6°2.6°174°
Perihelion10 Jan 20229.43.560 AU2.588 AU07h02m+31°09'169.6°2.9°150°
Today20 Oct 202517.211.168 AU11.856 AU12h55m-53°57'44.5°3.6°196°
C/2019 L3 (ATLAS)- 2025-10-20
astro.vanbuitenen.nl


 
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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 2.3 + 5 log[∆] + 9.0 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/2019 L3 (ATLAS) are:

    e (Eccentricity)                : 1.0033050
    q (Perihelion distance)         : 3.5601160
    i (Inclination)                 : 48.34680
    Ω (Longitude of ascending node) : 290.71110
    ω (Argument of perihelion)      : 171.77670
    L (Longitude of perihelion)     : 285.22472
    B (Latitude of perihelion)      : 6.13494
    T (Time of perihelion passage)  : 2459589.68850

    Epoch                           : 2025 Oct 19
    Reference                       : MPC185656

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

Ephemerides

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2025-10-19 00:00 UT   12 54 18.3   -53 53 59    11.846   11.161   44.8    3.6   194   17.2 
2025-10-20 00:00 UT   12 54 56.5   -53 56 31    11.854   11.167   44.6    3.6   195   17.2 
2025-10-20 06:14 UT   12 55 06.4   -53 57 11    11.856   11.168   44.5    3.6   196   17.2 
2025-10-21 00:00 UT   12 55 34.6   -53 59 07    11.862   11.173   44.4    3.6   196   17.2 
2025-10-22 00:00 UT   12 56 12.6   -54 01 44    11.870   11.179   44.2    3.6   198   17.2 
2025-10-23 00:00 UT   12 56 50.5   -54 04 25    11.878   11.185   44.1    3.5   199   17.2 
2025-10-24 00:00 UT   12 57 28.3   -54 07 07    11.886   11.191   43.9    3.5   200   17.2 
2025-10-25 00:00 UT   12 58 06.0   -54 09 52    11.894   11.197   43.8    3.5   201   17.2 
2025-10-26 00:00 UT   12 58 43.5   -54 12 40    11.901   11.203   43.7    3.5   202   17.2 
2025-10-27 00:00 UT   12 59 21.0   -54 15 30    11.908   11.209   43.6    3.5   204   17.2 
2025-10-28 00:00 UT   12 59 58.3   -54 18 22    11.915   11.215   43.5    3.5   205   17.2 
2025-10-29 00:00 UT   13 00 35.6   -54 21 17    11.922   11.221   43.4    3.5   206   17.2 
2025-10-30 00:00 UT   13 01 12.6   -54 24 14    11.929   11.227   43.3    3.5   207   17.2 



    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.