C/2019 JU6 (ATLAS)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Perihelion	2 Jun 2019	18.5	2.029 AU	1.501 AU	20h27m	+27°43'	106.0°	28.7°	234°
Nearest approach	25 Jun 2019	18.1	2.047 AU	1.279 AU	18h11m	+30°47'	125.8°	23.7°	179°
Today	15 Dec 2025	33.2	17.844 AU	17.523 AU	09h45m	-14°20'	107.5°	3.0°	301°

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. (14.5 + 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/2019 JU6 (ATLAS) are:

    e (Eccentricity)                : 0.9997630
    q (Perihelion distance)         : 2.0293530
    i (Inclination)                 : 148.28710
    Ω (Longitude of ascending node) : 21.65400
    ω (Argument of perihelion)      : 94.71210
    L (Longitude of perihelion)     : 106.11962
    B (Latitude of perihelion)      : 31.59331
    T (Time of perihelion passage)  : 2458637.37260
    P (Orbital period in years)     : 792344.19

    Epoch                           : 2025 Nov 12
    Reference                       : MPEC 2022-M21

    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
2025-12-14 00:00 UT   09 46 08.3   -14 19 08    17.540   17.835  105.9    3.0   300   33.2 
2025-12-15 00:00 UT   09 46 00.1   -14 20 01    17.530   17.840  106.8    3.0   300   33.2 
2025-12-15 17:45 UT   09 45 54.0   -14 20 39    17.523   17.844  107.5    3.0   301   33.2 
2025-12-16 00:00 UT   09 45 51.8   -14 20 53    17.521   17.846  107.7    3.0   301   33.2 
2025-12-17 00:00 UT   09 45 43.2   -14 21 43    17.511   17.851  108.7    3.0   301   33.2 
2025-12-18 00:00 UT   09 45 34.4   -14 22 31    17.502   17.857  109.6    3.0   302   33.2 
2025-12-19 00:00 UT   09 45 25.4   -14 23 17    17.493   17.862  110.5    3.0   302   33.2 
2025-12-20 00:00 UT   09 45 16.3   -14 24 02    17.484   17.867  111.4    2.9   303   33.2 
2025-12-21 00:00 UT   09 45 06.9   -14 24 45    17.475   17.873  112.3    2.9   303   33.2 
2025-12-22 00:00 UT   09 44 57.2   -14 25 26    17.466   17.878  113.3    2.9   304   33.2 
2025-12-23 00:00 UT   09 44 47.4   -14 26 05    17.458   17.884  114.2    2.9   304   33.2 
2025-12-24 00:00 UT   09 44 37.4   -14 26 43    17.449   17.889  115.1    2.9   305   33.2 
2025-12-25 00:00 UT   09 44 27.2   -14 27 18    17.441   17.895  116.0    2.8   306   33.2 

    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.