C/2019 Y1 (ATLAS)
ephemeris date magn radius delta ra dec elong phase PA
Perihelion17 Mar 20208.10.826 AU1.471 AU00h09m+30°45'32.4°40.2°10°
Nearest approach3 May 20209.81.195 AU1.092 AU06h10m+81°57'69.2°52.1°54°
Today19 Jun 202532.215.880 AU15.304 AU13h29m-44°37'123.0°3.1°91°
C/2019 Y1 (ATLAS)- 2025-06-19
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.)

The orbital elements of C/2019 Y1 (ATLAS) are:

            e (Eccentricity)                : 0.9906260
            q (Perihelion distance)         : 0.8264210
            i (Inclination)                 : 73.28270
            Ω (Longitude of ascending node) : 31.47960
            ω (Argument of perihelion)      : 57.91480
            L (Longitude of perihelion)     : 56.12602
            B (Latitude of perihelion)      : 54.23788
            T (Time of perihelion passage)  : 2458925.67730
            P (Orbital period in years)     : 827.78

            Epoch                           : 2025 Jun 18
            Reference                       : MPC119999

            Classification(s):              : Nearly isotropic; Returning (a < 10000 AU); External (P > 200 years); Liller
        

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 is based on the absolute magnitude and slope parameter as calculated from the original MPEC, or the latest values provided by the MPC (13.70 + 5 log[∆] + 10.00 log[r]), whereas the red curve is being recalculated every 6 hours based on the available COBS/MPC observations (currently 8.48 + 5 log[∆] + 14.81 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
2025-06-19 00:00 UT   13 29 16.9   -44 39 49    15.289   15.875  123.7    3.1    91   32.2 
2025-06-19 21:47 UT   13 29 09.0   -44 37 51    15.304   15.880  123.0    3.1    91   32.2 
2025-06-20 00:00 UT   13 29 08.2   -44 37 39    15.305   15.881  122.9    3.1    92   32.2 
2025-06-21 00:00 UT   13 28 59.9   -44 35 29    15.322   15.886  122.1    3.1    92   32.2 
2025-06-22 00:00 UT   13 28 51.9   -44 33 20    15.339   15.892  121.4    3.1    93   32.2 
2025-06-23 00:00 UT   13 28 44.2   -44 31 11    15.356   15.898  120.6    3.2    94   32.2 
2025-06-24 00:00 UT   13 28 36.9   -44 29 03    15.373   15.903  119.8    3.2    95   32.2 
2025-06-25 00:00 UT   13 28 29.9   -44 26 55    15.390   15.909  119.0    3.2    95   32.2 
2025-06-26 00:00 UT   13 28 23.3   -44 24 47    15.407   15.915  118.3    3.2    96   32.2 
2025-06-27 00:00 UT   13 28 17.0   -44 22 41    15.425   15.920  117.5    3.2    97   32.2 
2025-06-28 00:00 UT   13 28 11.0   -44 20 35    15.443   15.926  116.7    3.3    97   32.2 
2025-06-29 00:00 UT   13 28 05.4   -44 18 29    15.460   15.931  115.9    3.3    98   32.2 

































































    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.