C/2019 K1 (ATLAS)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Perihelion	9 Feb 2020	14.2	2.025 AU	2.319 AU	00h18m	-69°20'	60.6°	25.1°	132°
Nearest approach	21 Feb 2020	14.2	2.031 AU	2.299 AU	01h28m	-62°16'	61.9°	25.5°	124°
Today	4 Aug 2026	28.1	17.727 AU	18.147 AU	04h45m	+67°43'	64.1°	3.0°	289°

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)                : 0.9991450
    q (Perihelion distance)         : 2.0254980
    i (Inclination)                 : 87.04900
    Ω (Longitude of ascending node) : 73.34240
    ω (Argument of perihelion)      : 265.81100
    L (Longitude of perihelion)     : 108.44569
    B (Latitude of perihelion)      : -84.87744
    T (Time of perihelion passage)  : 2458889.34250
    P (Orbital period in years)     : 115305.11

    Epoch                           : 2026 May 29
    Reference                       : MPC194161

    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
2026-08-03 00:00 UT   04 45 06.5   +67 38 50    18.154   17.717   63.0    2.9   290   28.0 
2026-08-04 00:00 UT   04 45 23.3   +67 41 19    18.150   17.723   63.6    2.9   289   28.0 
2026-08-04 19:18 UT   04 45 36.4   +67 43 20    18.147   17.727   64.1    3.0   289   28.1 
2026-08-05 00:00 UT   04 45 39.6   +67 43 49    18.146   17.728   64.2    3.0   289   28.1 
2026-08-06 00:00 UT   04 45 55.5   +67 46 20    18.142   17.734   64.8    3.0   288   28.1 
2026-08-07 00:00 UT   04 46 11.0   +67 48 52    18.137   17.739   65.4    3.0   287   28.1 
2026-08-08 00:00 UT   04 46 26.1   +67 51 24    18.133   17.745   66.0    3.0   286   28.1 
2026-08-09 00:00 UT   04 46 40.7   +67 53 58    18.128   17.750   66.6    3.0   286   28.1 
2026-08-10 00:00 UT   04 46 54.8   +67 56 32    18.124   17.755   67.2    3.0   285   28.1 
2026-08-11 00:00 UT   04 47 08.5   +67 59 07    18.119   17.761   67.8    3.0   284   28.1 
2026-08-12 00:00 UT   04 47 21.8   +68 01 43    18.114   17.766   68.4    3.0   283   28.1 
2026-08-13 00:00 UT   04 47 34.5   +68 04 20    18.109   17.772   69.0    3.1   283   28.1 
2026-08-14 00:00 UT   04 47 46.8   +68 06 57    18.104   17.777   69.6    3.1   282   28.1 

    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.