C/2021 O3 (PANSTARRS) - DISINTEGRATED
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Disintegration	21 Apr 2022	9.4	0.285 AU	0.975 AU	02h50m	+03°14'	16.5°	87.6°	122°
Perihelion	21 Apr 2022	-	0.285 AU	0.963 AU	02h52m	+03°34'	16.5°	90.1°	121°
Nearest approach	8 May 2022	12.1	0.591 AU	0.605 AU	03h59m	+46°50'	32.0°	115.2°	27°
Today	4 Aug 2025	-	12.156 AU	11.613 AU	19h12m	+37°12'	120.2°	4.1°	151°

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.)

The orbital elements of C/2021 O3 (PANSTARRS) are:

            e (Eccentricity)                : 1.0000530
            q (Perihelion distance)         : 0.2850290
            i (Inclination)                 : 56.83120
            Ω (Longitude of ascending node) : 188.76900
            ω (Argument of perihelion)      : 300.02750
            L (Longitude of perihelion)     : 145.34132
            B (Latitude of perihelion)      : -46.44525
            T (Time of perihelion passage)  : 2459690.80630

            Epoch                           : 2025 Aug 03
            Reference                       : MPEC 2022-L66

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

The light curve chart below shows the estimated development of the comet's magnitude. Blue and black dots are visual and photometric CCD observations respectively from COBS or the MPC. The gray curve is based on the absolute magnitude and slope parameter as calculated from the original MPEC, or the latest values provided by the MPC (10.50 + 5 log[∆] + 10.00 log[r]), whereas the red curve is being recalculated every 6 hours based on the available COBS/MPC observations (currently 12.59 + 5 log[∆] + 5.68 log[r]). The additional green curve shows the effect of forward scattering, occurring when the comet is between the earth and the sun, for a gas-to-dust light ratio δ90 of 0.30. (See Marcus 2007)

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.
A more printer-friendly version of the same chart can be found further down this page as well.

The following chart shows the current location of the comet in a smaller, upside-down telescopic field of view.

A printable version of the short-term path of the comet in a field of view that is optimized for (~10x50) binoculars and finderscopes.

Ephemerides:

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2025-08-04 00:00 UT   19 13 01.8   +37 13 30    11.609   12.153  120.3    4.1   151   24.1 
2025-08-04 12:33 UT   19 12 51.0   +37 12 18    11.613   12.156  120.2    4.1   151   24.1 
2025-08-05 00:00 UT   19 12 41.3   +37 11 11    11.618   12.160  120.2    4.1   150   24.1 
2025-08-06 00:00 UT   19 12 20.9   +37 08 49    11.627   12.167  120.0    4.1   149   24.1 
2025-08-07 00:00 UT   19 12 00.8   +37 06 24    11.636   12.174  119.9    4.1   148   24.1 
2025-08-08 00:00 UT   19 11 41.0   +37 03 54    11.645   12.180  119.7    4.1   147   24.1 
2025-08-09 00:00 UT   19 11 21.4   +37 01 21    11.655   12.187  119.5    4.2   145   24.1 
2025-08-10 00:00 UT   19 11 02.0   +36 58 44    11.665   12.194  119.4    4.2   144   24.1 
2025-08-11 00:00 UT   19 10 43.0   +36 56 04    11.675   12.201  119.2    4.2   143   24.1 
2025-08-12 00:00 UT   19 10 24.2   +36 53 21    11.685   12.208  119.0    4.2   142   24.1 
2025-08-13 00:00 UT   19 10 05.7   +36 50 34    11.695   12.215  118.7    4.2   141   24.1 
2025-08-14 00:00 UT   19 09 47.5   +36 47 43    11.705   12.222  118.5    4.2   140   24.1 

    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.