C/2021 O3 (PANSTARRS) - DISINTEGRATED
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Disintegration	21 Apr 2022	9.4	0.285 AU	0.978 AU	02h50m	+03°12'	16.5°	87.1°	122°
Perihelion	21 Apr 2022	-	0.285 AU	0.964 AU	02h52m	+03°35'	16.5°	90.0°	121°
Nearest approach	8 May 2022	12.3	0.590 AU	0.605 AU	04h00m	+46°49'	32.0°	115.1°	27°
Today	7 Dec 2025	-	13.007 AU	13.434 AU	19h14m	+30°26'	62.4°	3.8°	36°

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 12.6 + 5 log[∆] + 5.7 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/2021 O3 (PANSTARRS) are:

    e (Eccentricity)                : 1.0000580
    q (Perihelion distance)         : 0.2849160
    i (Inclination)                 : 56.84220
    Ω (Longitude of ascending node) : 188.71010
    ω (Argument of perihelion)      : 300.05730
    L (Longitude of perihelion)     : 145.32515
    B (Latitude of perihelion)      : -46.43469
    T (Time of perihelion passage)  : 2459690.86630

    Epoch                           : 2025 Nov 12
    Reference                       : MPEC 2022-L66

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

Ephemerides

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2025-12-06 00:00 UT   19 13 59.2   +30 29 03    13.407   12.994   63.3    3.9    38   24.6 
2025-12-07 00:00 UT   19 14 18.1   +30 27 31    13.421   13.001   62.8    3.9    37   24.6 
2025-12-07 22:37 UT   19 14 36.0   +30 26 07    13.434   13.007   62.4    3.8    36   24.6 
2025-12-08 00:00 UT   19 14 37.1   +30 26 02    13.435   13.008   62.4    3.8    36   24.6 
2025-12-09 00:00 UT   19 14 56.3   +30 24 36    13.448   13.014   61.9    3.8    35   24.6 
2025-12-10 00:00 UT   19 15 15.6   +30 23 13    13.461   13.021   61.5    3.8    34   24.6 
2025-12-11 00:00 UT   19 15 35.1   +30 21 54    13.475   13.028   61.1    3.8    33   24.6 
2025-12-12 00:00 UT   19 15 54.6   +30 20 39    13.488   13.034   60.7    3.8    32   24.6 
2025-12-13 00:00 UT   19 16 14.3   +30 19 26    13.501   13.041   60.3    3.8    31   24.6 
2025-12-14 00:00 UT   19 16 34.1   +30 18 17    13.514   13.048   59.9    3.7    30   24.6 
2025-12-15 00:00 UT   19 16 54.0   +30 17 12    13.527   13.054   59.5    3.7    29   24.6 
2025-12-16 00:00 UT   19 17 14.1   +30 16 10    13.539   13.061   59.1    3.7    28   24.6 
2025-12-17 00:00 UT   19 17 34.2   +30 15 11    13.552   13.068   58.7    3.7    27   24.6 

    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.