C/2020 K8 (Catalina-ATLAS)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Nearest approach	15 Aug 2020	14.9	0.870 AU	0.574 AU	05h31m	+27°15'	59.0°	86.5°	270°
Perihelion	15 Sep 2020	15.5	0.471 AU	1.090 AU	09h52m	-00°46'	25.6°	67.1°	262°
Today	9 May 2025	25.4	15.210 AU	14.325 AU	16h06m	+08°13'	150.2°	1.9°	211°

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/2020 K8 (Catalina-ATLAS) are:

            e (Eccentricity)                : 1.0003110
            q (Perihelion distance)         : 0.4713840
            i (Inclination)                 : 31.38790
            Ω (Longitude of ascending node) : 181.32340
            ω (Argument of perihelion)      : 260.13820
            L (Longitude of perihelion)     : 259.81298
            B (Latitude of perihelion)      : -30.87277
            T (Time of perihelion passage)  : 2459108.15880

            Epoch                           : 2025 May 08
            Reference                       : MPEC 2021-P47

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

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 (15.00 + 5 log[∆] + 8.00 log[r]), whereas the red curve is being recalculated every 6 hours based on the available COBS/MPC observations (currently 16.24 + 5 log[∆] + 2.89 log[r]). The additional green curve shows the effect of forward scattering, occurring when the comet is between the earth and the sun, for a gas-to-dust light ratio δ90 of 0.30. (See Marcus 2007)

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
2025-05-09 00:00 UT   16 06 54.9   +08 13 16    14.324   15.208  150.1    1.9   212   25.4 
2025-05-09 09:15 UT   16 06 49.3   +08 13 43    14.325   15.210  150.2    1.9   211   25.4 
2025-05-10 00:00 UT   16 06 40.3   +08 14 25    14.328   15.214  150.3    1.9   210   25.4 
2025-05-11 00:00 UT   16 06 25.6   +08 15 33    14.332   15.220  150.6    1.9   208   25.4 
2025-05-12 00:00 UT   16 06 10.8   +08 16 40    14.336   15.226  150.8    1.9   206   25.4 
2025-05-13 00:00 UT   16 05 56.0   +08 17 44    14.340   15.232  151.0    1.8   203   25.4 
2025-05-14 00:00 UT   16 05 41.1   +08 18 46    14.345   15.238  151.1    1.8   201   25.4 
2025-05-15 00:00 UT   16 05 26.2   +08 19 47    14.350   15.245  151.3    1.8   199   25.4 
2025-05-16 00:00 UT   16 05 11.2   +08 20 45    14.355   15.251  151.3    1.8   197   25.4 
2025-05-17 00:00 UT   16 04 56.3   +08 21 41    14.361   15.257  151.4    1.8   195   25.4 
2025-05-18 00:00 UT   16 04 41.3   +08 22 36    14.367   15.263  151.4    1.8   193   25.4 
2025-05-19 00:00 UT   16 04 26.2   +08 23 28    14.373   15.269  151.4    1.8   191   25.4 

    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.