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°34'	57.0°	70.2°	128°
Nearest approach	28 Jun 2020	6.5	0.926 AU	0.817 AU	10h10m	-03°17'	59.5°	71.0°	120°
Today	18 Aug 2025	32.5	15.853 AU	15.464 AU	23h32m	+52°46'	110.9°	3.4°	206°

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)                : 0.9970060
            q (Perihelion distance)         : 0.9060300
            i (Inclination)                 : 60.99000
            Ω (Longitude of ascending node) : 235.74340
            ω (Argument of perihelion)      : 329.42480
            L (Longitude of perihelion)     : 219.75519
            B (Latitude of perihelion)      : -26.41366
            T (Time of perihelion passage)  : 2459018.83300
            P (Orbital period in years)     : 5264.25

            Epoch                           : 2025 Aug 18
            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[∆] + 15.89 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
2025-08-18 00:00 UT   23 32 44.0   +52 45 43    15.467   15.848  110.4    3.4   207   32.5 
2025-08-18 20:06 UT   23 32 28.3   +52 46 09    15.464   15.853  110.9    3.4   206   32.5 
2025-08-19 00:00 UT   23 32 25.3   +52 46 13    15.463   15.854  110.9    3.4   206   32.5 
2025-08-20 00:00 UT   23 32 06.4   +52 46 41    15.460   15.860  111.5    3.4   205   32.5 
2025-08-21 00:00 UT   23 31 47.4   +52 47 05    15.457   15.866  112.1    3.4   204   32.5 
2025-08-22 00:00 UT   23 31 28.2   +52 47 25    15.454   15.871  112.6    3.4   203   32.5 
2025-08-23 00:00 UT   23 31 08.8   +52 47 42    15.451   15.877  113.2    3.4   202   32.5 
2025-08-24 00:00 UT   23 30 49.3   +52 47 56    15.448   15.883  113.8    3.3   201   32.5 
2025-08-25 00:00 UT   23 30 29.6   +52 48 06    15.446   15.889  114.3    3.3   200   32.5 
2025-08-26 00:00 UT   23 30 09.7   +52 48 12    15.443   15.895  114.8    3.3   199   32.5 
2025-08-27 00:00 UT   23 29 49.7   +52 48 15    15.441   15.901  115.4    3.3   198   32.5 
2025-08-28 00:00 UT   23 29 29.6   +52 48 15    15.438   15.906  115.9    3.3   197   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.