C/2022 A3 (Lemmon-ATLAS)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Nearest approach	23 Feb 2023	17.0	4.172 AU	3.246 AU	09h15m	-05°32'	156.7°	5.4°	49°
Perihelion	29 Sep 2023	17.0	3.705 AU	4.256 AU	09h29m	-33°46'	50.8°	12.1°	241°
Today	1 Jun 2026	22.2	8.618 AU	8.432 AU	23h03m	-36°06'	97.1°	6.7°	248°

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)                : 0.9962890
    q (Perihelion distance)         : 3.7053740
    i (Inclination)                 : 88.36350
    Ω (Longitude of ascending node) : 325.44810
    ω (Argument of perihelion)      : 234.90150
    L (Longitude of perihelion)     : 327.77514
    B (Latitude of perihelion)      : -54.86826
    T (Time of perihelion passage)  : 2460216.69090
    P (Orbital period in years)     : 31550.89

    Epoch                           : 2026 May 31
    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
2026-05-31 00:00 UT   23 03 48.4   -36 05 08     8.441    8.611   96.3    6.7   247   22.2 
2026-06-01 00:00 UT   23 03 45.1   -36 06 30     8.432    8.618   97.1    6.7   248   22.2 
2026-06-01 00:10 UT   23 03 45.0   -36 06 31     8.432    8.618   97.1    6.7   248   22.2 
2026-06-02 00:00 UT   23 03 41.2   -36 07 55     8.424    8.624   98.0    6.7   248   22.2 
2026-06-03 00:00 UT   23 03 36.8   -36 09 23     8.415    8.630   98.9    6.7   249   22.2 
2026-06-04 00:00 UT   23 03 31.8   -36 10 53     8.406    8.636   99.7    6.6   249   22.2 
2026-06-05 00:00 UT   23 03 26.3   -36 12 26     8.398    8.642  100.6    6.6   250   22.2 
2026-06-06 00:00 UT   23 03 20.2   -36 14 02     8.389    8.649  101.5    6.6   250   22.2 
2026-06-07 00:00 UT   23 03 13.6   -36 15 40     8.381    8.655  102.4    6.6   251   22.2 
2026-06-08 00:00 UT   23 03 06.5   -36 17 21     8.372    8.661  103.2    6.6   251   22.2 
2026-06-09 00:00 UT   23 02 58.7   -36 19 04     8.364    8.667  104.1    6.5   252   22.2 
2026-06-10 00:00 UT   23 02 50.4   -36 20 49     8.355    8.674  105.0    6.5   252   22.2 
2026-06-11 00:00 UT   23 02 41.6   -36 22 37     8.347    8.680  105.8    6.5   253   22.2 

    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.