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	0.573 AU	05h31m	+27°00'	59.2°	86.4°	269°
Perihelion	15 Sep 2020	15.5	0.473 AU	1.090 AU	09h53m	-00°49'	25.7°	67.2°	262°
Today	16 Aug 2026	26.1	17.950 AU	17.886 AU	15h56m	+07°30'	92.0°	3.2°	104°

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)                : 1.0003650
    q (Perihelion distance)         : 0.4731330
    i (Inclination)                 : 31.29930
    Ω (Longitude of ascending node) : 181.12570
    ω (Argument of perihelion)      : 260.35640
    L (Longitude of perihelion)     : 259.87851
    B (Latitude of perihelion)      : -30.80831
    T (Time of perihelion passage)  : 2459108.38430

    Epoch                           : 2026 May 29
    Reference                       : MPC194168

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

Ephemerides

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2026-08-15 00:00 UT   15 56 51.6   +07 31 60    17.862   17.944   93.0    3.2   105   26.1 
2026-08-16 00:00 UT   15 56 50.7   +07 30 34    17.883   17.950   92.1    3.2   104   26.1 
2026-08-16 03:20 UT   15 56 50.6   +07 30 22    17.886   17.950   92.0    3.2   104   26.1 
2026-08-17 00:00 UT   15 56 50.0   +07 29 07    17.904   17.955   91.3    3.2   104   26.1 
2026-08-18 00:00 UT   15 56 49.5   +07 27 40    17.925   17.961   90.4    3.2   103   26.1 
2026-08-19 00:00 UT   15 56 49.3   +07 26 13    17.945   17.967   89.6    3.2   103   26.1 
2026-08-20 00:00 UT   15 56 49.2   +07 24 45    17.966   17.972   88.7    3.2   103   26.1 
2026-08-21 00:00 UT   15 56 49.4   +07 23 16    17.987   17.978   87.9    3.2   102   26.1 
2026-08-22 00:00 UT   15 56 49.8   +07 21 47    18.007   17.984   87.0    3.2   102   26.1 
2026-08-23 00:00 UT   15 56 50.4   +07 20 17    18.028   17.989   86.2    3.2   101   26.1 
2026-08-24 00:00 UT   15 56 51.2   +07 18 47    18.049   17.995   85.3    3.2   101   26.1 
2026-08-25 00:00 UT   15 56 52.2   +07 17 17    18.070   18.001   84.5    3.2   100   26.1 
2026-08-26 00:00 UT   15 56 53.5   +07 15 46    18.090   18.006   83.6    3.2   100   26.1 

    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.