C/2019 M3 (ATLAS)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Nearest approach	16 Dec 2018	13.8	2.428 AU	2.428 AU	17h24m	+54°54'	78.3°	23.4°	357°
Perihelion	1 Jan 2019	13.8	2.422 AU	2.465 AU	18h41m	+52°53'	75.9°	23.2°	359°
Today	26 Sep 2026	27.4	19.845 AU	19.319 AU	23h24m	-57°34'	120.3°	2.5°	14°

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 8.0 + 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 M3 (ATLAS) are:

    e (Eccentricity)                : 0.9996000
    q (Perihelion distance)         : 2.4216960
    i (Inclination)                 : 99.70280
    Ω (Longitude of ascending node) : 155.10540
    ω (Argument of perihelion)      : 87.92020
    L (Longitude of perihelion)     : 77.26519
    B (Latitude of perihelion)      : 80.07889
    T (Time of perihelion passage)  : 2458484.63720
    P (Orbital period in years)     : 471074.34

    Epoch                           : 2026 May 29
    Reference                       : MPC194162

    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
2026-09-25 00:00 UT   23 24 40.0   -57 33 52    19.297   19.836  121.2    2.5    12   27.4 
2026-09-26 00:00 UT   23 24 20.5   -57 34 18    19.309   19.841  120.7    2.5    13   27.4 
2026-09-26 18:31 UT   23 24 05.5   -57 34 36    19.319   19.845  120.3    2.5    14   27.4 
2026-09-27 00:00 UT   23 24 01.1   -57 34 41    19.322   19.846  120.2    2.5    14   27.4 
2026-09-28 00:00 UT   23 23 41.8   -57 35 01    19.335   19.851  119.7    2.5    15   27.4 
2026-09-29 00:00 UT   23 23 22.6   -57 35 19    19.348   19.856  119.1    2.5    16   27.4 
2026-09-30 00:00 UT   23 23 03.5   -57 35 33    19.362   19.861  118.6    2.5    17   27.4 
2026-10-01 00:00 UT   23 22 44.5   -57 35 45    19.375   19.866  118.1    2.5    18   27.4 
2026-10-02 00:00 UT   23 22 25.7   -57 35 54    19.389   19.872  117.5    2.6    19   27.4 
2026-10-03 00:00 UT   23 22 07.0   -57 36 01    19.403   19.877  116.9    2.6    20   27.4 
2026-10-04 00:00 UT   23 21 48.4   -57 36 04    19.417   19.882  116.4    2.6    21   27.4 
2026-10-05 00:00 UT   23 21 30.0   -57 36 05    19.431   19.887  115.8    2.6    22   27.4 
2026-10-06 00:00 UT   23 21 11.8   -57 36 02    19.445   19.892  115.2    2.6    23   27.4 

    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.