P/2026 R2 (Leonard)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Nearest approach	6 Oct 2026	16.1	0.857 AU	0.316 AU	16h27m	+00°32'	54.8°	107.6°	83°
Today	8 Oct 2026	16.0	0.849 AU	0.318 AU	16h27m	-05°12'	53.5°	109.0°	87°
Perihelion	25 Oct 2026	17.2	0.790 AU	0.582 AU	16h19m	-56°52'	52.5°	91.7°	134°

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. (19.4 + 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 P/2026 R2 (Leonard) are:

    e (Eccentricity)                : 0.8987270
    q (Perihelion distance)         : 0.7895310
    i (Inclination)                 : 78.09970
    Ω (Longitude of ascending node) : 179.23060
    ω (Argument of perihelion)      : 205.52630
    L (Longitude of perihelion)     : 184.85456
    B (Latitude of perihelion)      : -24.93968
    T (Time of perihelion passage)  : 2461338.73620
    P (Orbital period in years)     : 21.77

    Epoch                           : 2026 Oct 07
    Reference                       : MPEC 2026-TC6

    Classification(s):              : Nearly isotropic; Returning (a < 10000 AU); Halley type (P < 200 years)

Ephemerides

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2026-10-07 00:00 UT   16 27 13.4   +00 07 10     0.316    0.857   54.7  107.8    84   16.1 
2026-10-08 00:00 UT   16 27 53.3   -05 02 43     0.318    0.850   53.5  109.0    87   16.0 
2026-10-08 00:48 UT   16 27 54.5   -05 12 30     0.318    0.849   53.5  109.0    87   16.0 
2026-10-09 00:00 UT   16 28 26.8   -09 53 33     0.321    0.843   52.6  109.8    90   16.0 
2026-10-10 00:00 UT   16 28 53.6   -14 35 46     0.327    0.837   51.8  110.3    93   16.0 
2026-10-11 00:00 UT   16 29 13.3   -19 06 08     0.335    0.831   51.3  110.3    97   16.0 
2026-10-12 00:00 UT   16 29 25.8   -23 22 11     0.345    0.826   51.0  110.0   100   16.1 
2026-10-13 00:00 UT   16 29 30.7   -27 22 23     0.357    0.821   50.8  109.4   103   16.1 
2026-10-14 00:00 UT   16 29 28.0   -31 05 56     0.370    0.816   50.8  108.6   106   16.2 
2026-10-15 00:00 UT   16 29 17.3   -34 32 44     0.385    0.811   50.9  107.5   110   16.3 
2026-10-16 00:00 UT   16 28 58.5   -37 43 09     0.401    0.807   51.0  106.3   112   16.3 
2026-10-17 00:00 UT   16 28 31.5   -40 37 54     0.418    0.804   51.2  104.9   115   16.4 
2026-10-18 00:00 UT   16 27 56.3   -43 17 56     0.436    0.801   51.4  103.4   118   16.5 

    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.