C/2019 K1 (ATLAS)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Perihelion	10 Feb 2020	14.2	2.023 AU	2.317 AU	00h19m	-69°07'	60.5°	25.1°	132°
Nearest approach	22 Feb 2020	14.1	2.028 AU	2.297 AU	01h28m	-62°11'	61.9°	25.5°	125°
Today	21 Nov 2025	27.4	16.314 AU	15.656 AU	04h23m	+69°22'	130.4°	2.6°	190°

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 9.3 + 5 log[∆] + 10.0 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 K1 (ATLAS) are:

    e (Eccentricity)                : 0.9992320
    q (Perihelion distance)         : 2.0232880
    i (Inclination)                 : 87.02640
    Ω (Longitude of ascending node) : 73.31950
    ω (Argument of perihelion)      : 265.79570
    L (Longitude of perihelion)     : 108.52970
    B (Latitude of perihelion)      : -84.85194
    T (Time of perihelion passage)  : 2458889.92050
    P (Orbital period in years)     : 135221.18

    Epoch                           : 2025 Nov 12
    Reference                       : MPEC 2022-O08

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

Ephemerides

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2025-11-20 00:00 UT   04 24 31.3   +69 21 25    15.652   16.303  129.8    2.7   193   27.4 
2025-11-21 00:00 UT   04 23 48.1   +69 21 52    15.654   16.308  130.1    2.7   192   27.4 
2025-11-21 22:25 UT   04 23 07.6   +69 22 13    15.656   16.314  130.4    2.6   190   27.4 
2025-11-22 00:00 UT   04 23 04.8   +69 22 14    15.656   16.314  130.4    2.6   190   27.4 
2025-11-23 00:00 UT   04 22 21.3   +69 22 33    15.658   16.320  130.7    2.6   189   27.4 
2025-11-24 00:00 UT   04 21 37.8   +69 22 49    15.660   16.325  131.0    2.6   187   27.4 
2025-11-25 00:00 UT   04 20 54.1   +69 23 01    15.663   16.331  131.2    2.6   186   27.4 
2025-11-26 00:00 UT   04 20 10.5   +69 23 09    15.666   16.337  131.4    2.6   184   27.4 
2025-11-27 00:00 UT   04 19 26.8   +69 23 13    15.669   16.342  131.7    2.6   183   27.4 
2025-11-28 00:00 UT   04 18 43.1   +69 23 14    15.673   16.348  131.9    2.6   181   27.4 
2025-11-29 00:00 UT   04 17 59.4   +69 23 11    15.676   16.353  132.0    2.6   180   27.4 
2025-11-30 00:00 UT   04 17 15.7   +69 23 04    15.680   16.359  132.2    2.6   178   27.4 
2025-12-01 00:00 UT   04 16 32.1   +69 22 54    15.684   16.365  132.3    2.6   176   27.4 

    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.