C/2023 V5 (Leonard)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Nearest approach	3 Nov 2023	18.8	1.122 AU	0.225 AU	23h08m	-17°19'	120.1°	49.9°	60°
Perihelion	13 Dec 2023	20.5	0.846 AU	0.892 AU	18h40m	+26°44'	53.3°	68.9°	22°
Today	13 Sep 2026	36.9	10.377 AU	11.032 AU	13h35m	-32°16'	47.3°	4.1°	133°

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. (21.5 + 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/2023 V5 (Leonard) are:

    e (Eccentricity)                : 1.0080270
    q (Perihelion distance)         : 0.8463660
    i (Inclination)                 : 73.46460
    Ω (Longitude of ascending node) : 31.50060
    ω (Argument of perihelion)      : 57.02670
    L (Longitude of perihelion)     : 55.18789
    B (Latitude of perihelion)      : 53.53594
    T (Time of perihelion passage)  : 2460292.45420

    Epoch                           : 2026 May 29
    Reference                       : MPC194186

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

Ephemerides

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2026-09-12 00:00 UT   13 35 03.7   -32 14 04    10.998   10.363   48.8    4.2   132   36.9 
2026-09-13 00:00 UT   13 35 23.1   -32 15 08    11.016   10.371   48.0    4.1   133   36.9 
2026-09-13 20:47 UT   13 35 40.1   -32 16 06    11.032   10.377   47.3    4.1   133   36.9 
2026-09-14 00:00 UT   13 35 42.7   -32 16 15    11.034   10.378   47.2    4.1   133   36.9 
2026-09-15 00:00 UT   13 36 02.4   -32 17 24    11.053   10.385   46.4    4.0   134   36.9 
2026-09-16 00:00 UT   13 36 22.3   -32 18 36    11.070   10.393   45.7    4.0   134   36.9 
2026-09-17 00:00 UT   13 36 42.4   -32 19 50    11.088   10.400   44.9    3.9   135   36.9 
2026-09-18 00:00 UT   13 37 02.7   -32 21 06    11.106   10.408   44.1    3.9   136   36.9 
2026-09-19 00:00 UT   13 37 23.0   -32 22 24    11.123   10.415   43.3    3.8   136   36.9 
2026-09-20 00:00 UT   13 37 43.6   -32 23 45    11.140   10.423   42.5    3.7   137   36.9 
2026-09-21 00:00 UT   13 38 04.2   -32 25 07    11.157   10.430   41.8    3.7   138   36.9 
2026-09-22 00:00 UT   13 38 25.1   -32 26 32    11.173   10.437   41.0    3.6   138   36.9 
2026-09-23 00:00 UT   13 38 46.0   -32 27 60    11.190   10.445   40.3    3.6   139   36.9 

    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.