C/2019 Y1 (ATLAS)
ephemeris date magn radius delta ra dec elong phase PA
Perihelion15 Mar 20208.10.838 AU1.475 AU00h04m+30°32'32.9°40.2°10°
Nearest approach2 May 20209.81.208 AU1.106 AU05h48m+82°42'69.5°51.4°49°
Today8 May 202531.415.842 AU14.982 AU13h39m-44°45'147.4°2.0°39°
C/2019 Y1 (ATLAS)- 2025-05-08
astro.vanbuitenen.nl


 
-1 month
-1 week
-1 day
Now
+1 day
+1 week
+1 month

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)                : 0.9963515
            q (Perihelion distance)         : 0.8378025
            i (Inclination)                 : 73.35343
            Ω (Longitude of ascending node) : 31.36531
            ω (Argument of perihelion)      : 57.49437
            L (Longitude of perihelion)     : 55.57237
            B (Latitude of perihelion)      : 53.90044
            T (Time of perihelion passage)  : 2458924.05444
            P (Orbital period in years)     : 3479.69

            Epoch                           : 2020 Dec 17
            Reference                       : MPEC 2020-SI8

            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 8.38 + 5 log[∆] + 14.30 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
2025-05-08 00:00 UT   13 39 52.9   -44 46 51    14.975   15.837  147.6    2.0    37   31.4 
2025-05-08 22:02 UT   13 39 35.2   -44 45 24    14.982   15.842  147.4    2.0    39   31.4 
2025-05-09 00:00 UT   13 39 33.6   -44 45 17    14.982   15.843  147.4    2.0    39   31.4 
2025-05-10 00:00 UT   13 39 14.4   -44 43 41    14.990   15.848  147.2    2.0    41   31.4 
2025-05-11 00:00 UT   13 38 55.5   -44 42 03    14.998   15.854  146.9    2.0    43   31.4 
2025-05-12 00:00 UT   13 38 36.6   -44 40 24    15.006   15.860  146.6    2.0    45   31.4 
2025-05-13 00:00 UT   13 38 18.0   -44 38 43    15.015   15.866  146.3    2.0    47   31.4 
2025-05-14 00:00 UT   13 37 59.6   -44 37 00    15.024   15.872  146.0    2.0    48   31.4 
2025-05-15 00:00 UT   13 37 41.3   -44 35 16    15.033   15.878  145.6    2.1    50   31.4 
2025-05-16 00:00 UT   13 37 23.3   -44 33 31    15.042   15.883  145.2    2.1    52   31.4 
2025-05-17 00:00 UT   13 37 05.5   -44 31 44    15.051   15.889  144.8    2.1    54   31.4 
2025-05-18 00:00 UT   13 36 47.9   -44 29 55    15.061   15.895  144.4    2.1    55   31.4 

































































    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.