C/2019 U6 (Lemmon)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Perihelion	18 Jun 2020	6.5	0.905 AU	0.861 AU	08h52m	-11°31'	56.9°	70.2°	128°
Nearest approach	29 Jun 2020	6.5	0.925 AU	0.818 AU	10h10m	-03°14'	59.4°	71.1°	119°
Today	28 Jan 2026	33.1	16.790 AU	17.035 AU	23h15m	+47°03'	74.0°	3.2°	38°

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 7.5 + 5 log[∆] + 15.9 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/2019 U6 (Lemmon) are:

    e (Eccentricity)                : 0.9969930
    q (Perihelion distance)         : 0.9050780
    i (Inclination)                 : 61.00170
    Ω (Longitude of ascending node) : 235.72230
    ω (Argument of perihelion)      : 329.41850
    L (Longitude of perihelion)     : 219.73587
    B (Latitude of perihelion)      : -26.42218
    T (Time of perihelion passage)  : 2459018.88680
    P (Orbital period in years)     : 5221.90

    Epoch                           : 2025 Nov 12
    Reference                       : MPEC 2022-H04

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

Ephemerides

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2026-01-27 00:00 UT   23 15 26.7   +47 04 31    17.014   16.783   74.8    3.2    39   33.1 
2026-01-28 00:00 UT   23 15 43.0   +47 03 21    17.030   16.788   74.1    3.2    38   33.1 
2026-01-28 06:13 UT   23 15 47.2   +47 03 04    17.035   16.790   74.0    3.2    38   33.1 
2026-01-29 00:00 UT   23 15 59.4   +47 02 14    17.047   16.794   73.5    3.2    37   33.1 
2026-01-30 00:00 UT   23 16 15.9   +47 01 10    17.064   16.800   72.8    3.2    37   33.1 
2026-01-31 00:00 UT   23 16 32.7   +47 00 09    17.080   16.805   72.2    3.2    36   33.1 
2026-02-01 00:00 UT   23 16 49.6   +46 59 10    17.097   16.811   71.5    3.2    35   33.1 
2026-02-02 00:00 UT   23 17 06.6   +46 58 14    17.113   16.817   70.9    3.2    35   33.1 
2026-02-03 00:00 UT   23 17 23.8   +46 57 21    17.129   16.822   70.2    3.2    34   33.1 
2026-02-04 00:00 UT   23 17 41.1   +46 56 30    17.146   16.828   69.6    3.1    33   33.1 
2026-02-05 00:00 UT   23 17 58.6   +46 55 43    17.162   16.834   69.0    3.1    32   33.1 
2026-02-06 00:00 UT   23 18 16.2   +46 54 58    17.178   16.839   68.4    3.1    31   33.1 
2026-02-07 00:00 UT   23 18 33.9   +46 54 16    17.194   16.845   67.7    3.1    31   33.1 

    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.