C/2024 J3 (ATLAS)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Today	25 May 2026	14.5	4.184 AU	3.851 AU	20h20m	+26°51'	102.2°	13.7°	239°
Nearest approach	25 Jul 2026	14.1	4.011 AU	3.445 AU	19h21m	+41°51'	117.1°	13.0°	165°
Perihelion	25 Nov 2026	14.3	3.865 AU	4.024 AU	18h55m	+41°11'	73.7°	14.2°	42°

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 5.4 + 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/2024 J3 (ATLAS) are:

    e (Eccentricity)                : 1.0001210
    q (Perihelion distance)         : 3.8654620
    i (Inclination)                 : 75.64040
    Ω (Longitude of ascending node) : 285.96080
    ω (Argument of perihelion)      : 74.09030
    L (Longitude of perihelion)     : 326.98654
    B (Latitude of perihelion)      : 68.69348
    T (Time of perihelion passage)  : 2461369.91920

    Epoch                           : 2026 May 24
    Reference                       : MPEC 2026-K60

    Classification(s):              : Nearly isotropic; New (a > 10000 AU)

Ephemerides

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2026-05-24 00:00 UT   20 20 35.0   +26 30 04     3.866    4.188  101.5   13.7   240   14.6 
2026-05-25 00:00 UT   20 20 14.1   +26 48 35     3.853    4.184  102.1   13.7   239   14.5 
2026-05-25 04:00 UT   20 20 10.5   +26 51 40     3.851    4.184  102.2   13.7   239   14.5 
2026-05-26 00:00 UT   20 19 52.0   +27 07 05     3.840    4.181  102.7   13.7   238   14.5 
2026-05-27 00:00 UT   20 19 28.6   +27 25 34     3.828    4.178  103.3   13.7   237   14.5 
2026-05-28 00:00 UT   20 19 04.0   +27 44 03     3.815    4.175  103.8   13.6   236   14.5 
2026-05-29 00:00 UT   20 18 38.2   +28 02 30     3.803    4.171  104.4   13.6   236   14.5 
2026-05-30 00:00 UT   20 18 11.1   +28 20 56     3.791    4.168  104.9   13.6   235   14.5 
2026-05-31 00:00 UT   20 17 42.8   +28 39 19     3.779    4.165  105.5   13.6   234   14.5 
2026-06-01 00:00 UT   20 17 13.3   +28 57 40     3.767    4.162  106.0   13.5   233   14.5 
2026-06-02 00:00 UT   20 16 42.4   +29 15 59     3.755    4.159  106.5   13.5   232   14.5 
2026-06-03 00:00 UT   20 16 10.3   +29 34 15     3.744    4.156  107.0   13.5   231   14.5 
2026-06-04 00:00 UT   20 15 36.9   +29 52 28     3.733    4.152  107.5   13.5   230   14.4 

    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.