A/2019 O2
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Perihelion	5 Apr 2023	19.5	9.680 AU	9.208 AU	16h34m	+32°52'	115.4°	5.4°	243°
Nearest approach	16 May 2023	19.5	9.682 AU	9.046 AU	16h14m	+33°22'	126.6°	4.8°	193°
Today	8 Dec 2025	20.1	10.841 AU	11.712 AU	15h24m	-08°48'	26.6°	2.3°	304°

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 displayed light curve is calculated under the assumption that the object remains inactive. (H=9.35; G=.15).

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 A/2019 O2 are:

    e (Eccentricity)                : 0.8354420
    q (Perihelion distance)         : 9.6803110
    i (Inclination)                 : 93.29020
    Ω (Longitude of ascending node) : 48.26510
    ω (Argument of perihelion)      : 129.56590
    L (Longitude of perihelion)     : 52.23852
    B (Latitude of perihelion)      : 50.31994
    T (Time of perihelion passage)  : 2460040.44490
    P (Orbital period in years)     : 451.19

    Epoch                           : 2025 Dec 07
    Reference                       : MPC185656

    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
2025-12-07 00:00 UT   15 24 25.8   -08 45 28    11.718   10.838   25.5    2.2   305   20.1 
2025-12-08 00:00 UT   15 24 41.8   -08 48 08    11.714   10.840   26.4    2.3   304   20.1 
2025-12-08 06:26 UT   15 24 46.1   -08 48 51    11.712   10.841   26.6    2.3   304   20.1 
2025-12-09 00:00 UT   15 24 57.7   -08 50 48    11.708   10.842   27.2    2.4   304   20.1 
2025-12-10 00:00 UT   15 25 13.5   -08 53 27    11.703   10.844   28.1    2.5   303   20.1 
2025-12-11 00:00 UT   15 25 29.1   -08 56 04    11.697   10.847   29.0    2.5   302   20.1 
2025-12-12 00:00 UT   15 25 44.6   -08 58 40    11.691   10.849   29.9    2.6   301   20.1 
2025-12-13 00:00 UT   15 26 00.0   -09 01 14    11.685   10.851   30.8    2.7   301   20.1 
2025-12-14 00:00 UT   15 26 15.3   -09 03 48    11.679   10.853   31.6    2.7   300   20.2 
2025-12-15 00:00 UT   15 26 30.4   -09 06 20    11.672   10.855   32.5    2.8   299   20.2 
2025-12-16 00:00 UT   15 26 45.3   -09 08 51    11.665   10.858   33.4    2.9   299   20.2 
2025-12-17 00:00 UT   15 27 00.1   -09 11 20    11.658   10.860   34.3    2.9   298   20.2 
2025-12-18 00:00 UT   15 27 14.7   -09 13 49    11.651   10.862   35.2    3.0   298   20.2 

    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.