C/2022 A3 (Lemmon-ATLAS)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Nearest approach	23 Feb 2023	17.0	4.173 AU	3.246 AU	09h15m	-05°32'	156.7°	5.4°	49°
Perihelion	29 Sep 2023	17.0	3.706 AU	4.256 AU	09h29m	-33°46'	50.8°	12.1°	241°
Today	13 Jul 2026	22.2	8.881 AU	8.148 AU	22h52m	-37°32'	133.6°	4.8°	275°

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 8.2 + 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/2022 A3 (Lemmon-ATLAS) are:

    e (Eccentricity)                : 0.9963530
    q (Perihelion distance)         : 3.7055010
    i (Inclination)                 : 88.36390
    Ω (Longitude of ascending node) : 325.44790
    ω (Argument of perihelion)      : 234.90540
    L (Longitude of perihelion)     : 327.77470
    B (Latitude of perihelion)      : -54.87217
    T (Time of perihelion passage)  : 2460216.72940
    P (Orbital period in years)     : 32386.70

    Epoch                           : 2026 Jul 12
    Reference                       : MPC194178

    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
2026-07-12 00:00 UT   22 53 28.4   -37 29 45     8.153    8.873  132.6    4.8   274   22.2 
2026-07-13 00:00 UT   22 53 01.9   -37 32 01     8.149    8.879  133.4    4.8   275   22.2 
2026-07-13 07:10 UT   22 52 53.9   -37 32 42     8.148    8.881  133.6    4.8   275   22.2 
2026-07-14 00:00 UT   22 52 34.9   -37 34 17     8.146    8.885  134.2    4.7   276   22.2 
2026-07-15 00:00 UT   22 52 07.5   -37 36 32     8.143    8.891  135.0    4.6   276   22.2 
2026-07-16 00:00 UT   22 51 39.6   -37 38 46     8.140    8.898  135.8    4.6   278   22.2 
2026-07-17 00:00 UT   22 51 11.2   -37 40 59     8.138    8.904  136.6    4.5   279   22.2 
2026-07-18 00:00 UT   22 50 42.4   -37 43 12     8.135    8.910  137.4    4.4   280   22.2 
2026-07-19 00:00 UT   22 50 13.1   -37 45 22     8.133    8.916  138.2    4.4   281   22.2 
2026-07-20 00:00 UT   22 49 43.3   -37 47 32     8.131    8.922  138.9    4.3   282   22.2 
2026-07-21 00:00 UT   22 49 13.1   -37 49 40     8.129    8.929  139.7    4.2   283   22.2 
2026-07-22 00:00 UT   22 48 42.5   -37 51 47     8.128    8.935  140.4    4.2   284   22.3 
2026-07-23 00:00 UT   22 48 11.5   -37 53 52     8.127    8.941  141.2    4.1   286   22.3 

    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.