C/2022 U1 (Leonard)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Nearest approach	28 Oct 2023	16.8	4.385 AU	3.683 AU	23h54m	+56°10'	129.7°	10.0°	136°
Perihelion	26 Mar 2024	17.3	4.201 AU	4.895 AU	22h49m	+38°08'	41.6°	9.1°	324°
Today	15 Jul 2026	20.7	7.798 AU	6.965 AU	17h13m	-09°02'	142.7°	4.5°	114°

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 7.6 + 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 U1 (Leonard) are:

    e (Eccentricity)                : 1.0007030
    q (Perihelion distance)         : 4.2014840
    i (Inclination)                 : 128.13670
    Ω (Longitude of ascending node) : 72.53440
    ω (Argument of perihelion)      : 78.61430
    L (Longitude of perihelion)     : 0.59521
    B (Latitude of perihelion)      : 50.44925
    T (Time of perihelion passage)  : 2460395.72980

    Epoch                           : 2026 Jul 15
    Reference                       : MPC194182

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

Ephemerides

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2026-07-14 00:00 UT   17 14 21.8   -08 56 38     6.936    7.787  144.6    4.3   115   20.7 
2026-07-15 00:00 UT   17 13 45.3   -08 59 36     6.951    7.793  143.6    4.4   114   20.7 
2026-07-15 22:13 UT   17 13 12.0   -09 02 22     6.965    7.798  142.7    4.5   114   20.7 
2026-07-16 00:00 UT   17 13 09.3   -09 02 35     6.967    7.799  142.6    4.5   114   20.7 
2026-07-17 00:00 UT   17 12 33.8   -09 05 35     6.982    7.805  141.6    4.6   113   20.7 
2026-07-18 00:00 UT   17 11 58.7   -09 08 36     6.998    7.811  140.6    4.7   112   20.7 
2026-07-19 00:00 UT   17 11 24.1   -09 11 38     7.014    7.817  139.6    4.8   112   20.7 
2026-07-20 00:00 UT   17 10 50.1   -09 14 41     7.031    7.823  138.6    4.9   111   20.7 
2026-07-21 00:00 UT   17 10 16.5   -09 17 44     7.048    7.828  137.6    5.0   110   20.7 
2026-07-22 00:00 UT   17 09 43.4   -09 20 49     7.065    7.834  136.6    5.1   110   20.8 
2026-07-23 00:00 UT   17 09 10.9   -09 23 55     7.082    7.840  135.6    5.2   109   20.8 
2026-07-24 00:00 UT   17 08 38.8   -09 27 01     7.099    7.846  134.6    5.3   109   20.8 
2026-07-25 00:00 UT   17 08 07.3   -09 30 08     7.117    7.852  133.6    5.4   108   20.8 

    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.