C/2022 K1 (Leonard)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Perihelion	16 Dec 2021	20.4	3.983 AU	4.844 AU	18h45m	-03°24'	26.1°	6.2°	39°
Nearest approach	28 Jul 2022	20.1	4.418 AU	3.426 AU	21h24m	-14°22'	165.7°	3.2°	249°
Today	31 Dec 2025	26.9	11.579 AU	11.463 AU	02h01m	-30°25'	94.3°	4.9°	60°

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. The light curve is based on the absolute magnitude and slope parameter as calculated from an MPEC, or the latest values provided by the minor planet center. (11.0 + 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/2022 K1 (Leonard) are:

    e (Eccentricity)                : 1.0004880
    q (Perihelion distance)         : 3.9833890
    i (Inclination)                 : 41.97740
    Ω (Longitude of ascending node) : 136.37170
    ω (Argument of perihelion)      : 142.49630
    L (Longitude of perihelion)     : 106.66634
    B (Latitude of perihelion)      : 24.02886
    T (Time of perihelion passage)  : 2459564.88420

    Epoch                           : 2025 Dec 30
    Reference                       : MPEC 2022-ST7

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

Ephemerides

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2025-12-30 00:00 UT   02 01 05.2   -30 28 21    11.443   11.573   95.1    4.9    59   26.9 
2025-12-31 00:00 UT   02 01 02.4   -30 25 25    11.462   11.579   94.3    4.9    60   26.9 
2025-12-31 00:40 UT   02 01 02.3   -30 25 20    11.463   11.579   94.3    4.9    60   26.9 
2026-01-01 00:00 UT   02 00 60.0   -30 22 27    11.481   11.584   93.6    4.9    61   26.9 
2026-01-02 00:00 UT   02 00 57.9   -30 19 26    11.500   11.590   92.8    4.9    61   26.9 
2026-01-03 00:00 UT   02 00 56.3   -30 16 24    11.519   11.596   92.0    4.9    62   27.0 
2026-01-04 00:00 UT   02 00 55.0   -30 13 20    11.538   11.602   91.3    4.9    63   27.0 
2026-01-05 00:00 UT   02 00 54.0   -30 10 13    11.557   11.607   90.5    4.9    63   27.0 
2026-01-06 00:00 UT   02 00 53.5   -30 07 05    11.576   11.613   89.7    4.9    64   27.0 
2026-01-07 00:00 UT   02 00 53.3   -30 03 56    11.595   11.619   89.0    4.9    64   27.0 
2026-01-08 00:00 UT   02 00 53.5   -30 00 44    11.613   11.625   88.2    4.9    65   27.0 
2026-01-09 00:00 UT   02 00 54.1   -29 57 31    11.632   11.631   87.4    4.8    66   27.0 
2026-01-10 00:00 UT   02 00 55.1   -29 54 16    11.651   11.636   86.7    4.8    66   27.0 

    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.