C/2020 K8 (Catalina-ATLAS)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Nearest approach	15 Aug 2020	14.9	0.871 AU	0.572 AU	05h31m	+27°05'	59.2°	86.5°	269°
Perihelion	15 Sep 2020	15.5	0.473 AU	1.089 AU	09h53m	-00°49'	25.7°	67.2°	262°
Today	10 May 2026	25.9	17.388 AU	16.508 AU	16h11m	+08°05'	149.7°	1.7°	212°

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 16.2 + 5 log[∆] + 2.9 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/2020 K8 (Catalina-ATLAS) are:

    e (Eccentricity)                : 1.0003570
    q (Perihelion distance)         : 0.4725710
    i (Inclination)                 : 31.31010
    Ω (Longitude of ascending node) : 181.16350
    ω (Argument of perihelion)      : 260.31130
    L (Longitude of perihelion)     : 259.86281
    B (Latitude of perihelion)      : -30.81432
    T (Time of perihelion passage)  : 2459108.38480

    Epoch                           : 2026 Mar 16
    Reference                       : MPEC 2026-E44

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

Ephemerides

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2026-05-09 00:00 UT   16 12 04.4   +08 04 40    16.505   17.382  149.4    1.7   214   25.9 
2026-05-10 00:00 UT   16 11 51.7   +08 05 42    16.508   17.388  149.7    1.7   212   25.9 
2026-05-10 01:04 UT   16 11 51.1   +08 05 44    16.508   17.388  149.7    1.7   212   25.9 
2026-05-11 00:00 UT   16 11 38.9   +08 06 42    16.511   17.394  150.0    1.7   210   25.9 
2026-05-12 00:00 UT   16 11 26.0   +08 07 41    16.515   17.400  150.3    1.6   208   25.9 
2026-05-13 00:00 UT   16 11 13.1   +08 08 38    16.518   17.405  150.5    1.6   206   25.9 
2026-05-14 00:00 UT   16 11 00.1   +08 09 33    16.522   17.411  150.7    1.6   204   25.9 
2026-05-15 00:00 UT   16 10 47.1   +08 10 27    16.526   17.417  150.9    1.6   202   25.9 
2026-05-16 00:00 UT   16 10 34.1   +08 11 19    16.531   17.423  151.0    1.6   200   25.9 
2026-05-17 00:00 UT   16 10 21.0   +08 12 10    16.535   17.428  151.2    1.6   198   25.9 
2026-05-18 00:00 UT   16 10 07.9   +08 12 58    16.540   17.434  151.2    1.6   196   25.9 
2026-05-19 00:00 UT   16 09 54.7   +08 13 45    16.546   17.440  151.3    1.6   194   25.9 
2026-05-20 00:00 UT   16 09 41.6   +08 14 30    16.551   17.446  151.3    1.6   192   25.9 

    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.