C/2019 U6 (Lemmon)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Perihelion	18 Jun 2020	6.5	0.906 AU	0.860 AU	08h52m	-11°35'	57.1°	70.2°	128°
Nearest approach	28 Jun 2020	6.5	0.926 AU	0.817 AU	10h10m	-03°18'	59.5°	71.0°	120°
Today	18 Jul 2025	32.5	15.672 AU	15.605 AU	23h40m	+52°06'	91.9°	3.7°	231°

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.)

The orbital elements of C/2019 U6 (Lemmon) are:

            e (Eccentricity)                : 0.9970130
            q (Perihelion distance)         : 0.9063770
            i (Inclination)                 : 60.98740
            Ω (Longitude of ascending node) : 235.74820
            ω (Argument of perihelion)      : 329.42870
            L (Longitude of perihelion)     : 219.76111
            B (Latitude of perihelion)      : -26.40966
            T (Time of perihelion passage)  : 2459018.82220
            P (Orbital period in years)     : 5285.80

            Epoch                           : 2025 Jul 17
            Reference                       : MPEC 2022-H04

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

The light curve chart below shows the estimated development of the comet's magnitude. Blue and black dots are visual and photometric CCD observations respectively from COBS or the MPC. The gray curve is based on the absolute magnitude and slope parameter as calculated from the original MPEC, or the latest values provided by the MPC (10.00 + 5 log[∆] + 10.00 log[r]), whereas the red curve is being recalculated every 6 hours based on the available COBS/MPC observations (currently 7.50 + 5 log[∆] + 15.90 log[r]).

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.
A more printer-friendly version of the same chart can be found further down this page as well.

The following chart shows the current location of the comet in a smaller, upside-down telescopic field of view.

A printable version of the short-term path of the comet in a field of view that is optimized for (~10x50) binoculars and finderscopes.

Ephemerides:

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2025-07-18 00:00 UT   23 40 15.3   +52 04 18    15.610   15.666   91.3    3.7   232   32.5 
2025-07-18 22:49 UT   23 40 05.9   +52 06 13    15.605   15.672   91.9    3.7   231   32.5 
2025-07-19 00:00 UT   23 40 05.4   +52 06 19    15.605   15.672   91.9    3.7   231   32.5 
2025-07-20 00:00 UT   23 39 55.1   +52 08 18    15.600   15.678   92.5    3.7   231   32.5 
2025-07-21 00:00 UT   23 39 44.5   +52 10 14    15.594   15.684   93.2    3.7   230   32.5 
2025-07-22 00:00 UT   23 39 33.5   +52 12 08    15.589   15.690   93.8    3.7   229   32.5 
2025-07-23 00:00 UT   23 39 22.2   +52 13 59    15.584   15.696   94.4    3.7   228   32.5 
2025-07-24 00:00 UT   23 39 10.5   +52 15 48    15.579   15.701   95.1    3.7   228   32.5 
2025-07-25 00:00 UT   23 38 58.5   +52 17 35    15.573   15.707   95.7    3.7   227   32.5 
2025-07-26 00:00 UT   23 38 46.2   +52 19 19    15.568   15.713   96.3    3.7   226   32.5 
2025-07-27 00:00 UT   23 38 33.6   +52 20 60    15.563   15.719   97.0    3.7   225   32.5 
2025-07-28 00:00 UT   23 38 20.6   +52 22 38    15.558   15.725   97.6    3.7   225   32.5 

    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.