Skip Navigation Links

C/2025 A4 (PANSTARRS)
ephemeris date magn radius delta ra dec elong phase PA
Perihelion13 Jan 202521.03.824 AU3.545 AU 13h40m+26°16'99.0°14.7°290°
Nearest approach28 Mar 202520.73.861 AU3.023 AU 13h40m+30°36'142.3°9.1°209°
Today11 Jan 202622.64.579 AU5.124 AU 16h00m-09°45'51.6°9.7°290°
C/2025 A4 (PANSTARRS)- 2026-01-11
astro.vanbuitenen.nl


 
-1 month
-1 week
-1 day
Now
+1 day
+1 week
+1 month

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 light curve is based on the absolute magnitude and slope parameter as calculated from an MPEC, or the latest values provided by the minor planet center. (12.4 + 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/2025 A4 (PANSTARRS) are: 

    e (Eccentricity)                : 0.6543160
    q (Perihelion distance)         : 3.8244030
    i (Inclination)                 : 32.02380
    Ω (Longitude of ascending node) : 69.91550
    ω (Argument of perihelion)      : 102.81080
    L (Longitude of perihelion)     : -5.07076
    B (Latitude of perihelion)      : 31.13603
    T (Time of perihelion passage)  : 2460688.77550
    P (Orbital period in years)     : 36.80

    Epoch                           : 2026 Jan 10
    Reference                       : MPC185660

    Classification(s):              : Nearly isotropic; Returning (a < 10000 AU); Halley type (P < 200 years)

Ephemerides

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2026-01-10 00:00 UT   15 59 17.4   -09 39 57     5.136    4.574   50.5    9.5   291   22.6 
2026-01-11 00:00 UT   16 00 05.5   -09 44 03     5.128    4.577   51.3    9.6   290   22.6 
2026-01-11 09:55 UT   16 00 25.3   -09 45 44     5.124    4.579   51.6    9.7   290   22.6 
2026-01-12 00:00 UT   16 00 53.2   -09 48 06     5.119    4.581   52.1    9.7   290   22.6 
2026-01-13 00:00 UT   16 01 40.5   -09 52 07     5.111    4.584   52.8    9.8   290   22.6 
2026-01-14 00:00 UT   16 02 27.3   -09 56 04     5.102    4.588   53.6    9.9   289   22.6 
2026-01-15 00:00 UT   16 03 13.6   -09 59 58     5.094    4.592   54.4   10.0   289   22.6 
2026-01-16 00:00 UT   16 03 59.5   -10 03 50     5.085    4.595   55.2   10.1   289   22.6 
2026-01-17 00:00 UT   16 04 44.9   -10 07 39     5.076    4.599   56.0   10.2   288   22.6 
2026-01-18 00:00 UT   16 05 29.9   -10 11 25     5.067    4.603   56.8   10.3   288   22.6 
2026-01-19 00:00 UT   16 06 14.3   -10 15 08     5.058    4.606   57.6   10.4   288   22.6 
2026-01-20 00:00 UT   16 06 58.3   -10 18 48     5.048    4.610   58.4   10.5   288   22.6 
2026-01-21 00:00 UT   16 07 41.7   -10 22 26     5.039    4.614   59.2   10.6   287   22.6 




    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.

Privacy policy