A/2025 A1
ephemeris date magn radius delta ra dec elong phase PA
Today17 Jun 202520.37.046 AU7.989 AU07h12m+26°53'20.6°2.9°85°
Nearest approach5 Mar 202718.65.343 AU4.517 AU12h13m+39°26'143.0°6.4°210°
Perihelion12 Mar 202718.65.342 AU4.522 AU12h11m+39°53'142.3°6.5°198°
A/2025 A1- 2025-06-17
astro.vanbuitenen.nl


 
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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 A/2025 A1 are:

            e (Eccentricity)                : 1.0042080
            q (Perihelion distance)         : 5.3423110
            i (Inclination)                 : 33.43940
            Ω (Longitude of ascending node) : 101.33030
            ω (Argument of perihelion)      : 68.06630
            L (Longitude of perihelion)     : 165.57024
            B (Latitude of perihelion)      : 30.74163
            T (Time of perihelion passage)  : 2461476.80160

            Epoch                           : 2025 Jun 16
            Reference                       : MPC182884

            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 indicates the expected brightness if this object is a comet (11.80 + 5 log[∆] + 5.00 log[r]), whereas the red curve indicates the expected lightcurve for an asteroid (H=11.20; G=.15).


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
2025-06-17 00:00 UT   07 12 21.5   +26 53 08     7.988    7.048   20.9    2.9    85   20.3 
2025-06-17 09:49 UT   07 12 39.3   +26 53 19     7.989    7.046   20.6    2.9    85   20.3 
2025-06-18 00:00 UT   07 13 05.2   +26 53 36     7.989    7.044   20.1    2.8    85   20.2 
2025-06-19 00:00 UT   07 13 49.0   +26 54 03     7.990    7.039   19.3    2.7    84   20.2 
2025-06-20 00:00 UT   07 14 33.1   +26 54 29     7.991    7.035   18.6    2.6    84   20.2 
2025-06-21 00:00 UT   07 15 17.3   +26 54 55     7.991    7.030   17.8    2.5    83   20.2 
2025-06-22 00:00 UT   07 16 01.7   +26 55 21     7.991    7.026   17.1    2.4    82   20.2 
2025-06-23 00:00 UT   07 16 46.2   +26 55 45     7.991    7.021   16.3    2.3    81   20.2 
2025-06-24 00:00 UT   07 17 31.0   +26 56 09     7.991    7.017   15.6    2.2    81   20.2 
2025-06-25 00:00 UT   07 18 15.8   +26 56 33     7.990    7.012   14.8    2.1    80   20.2 
2025-06-26 00:00 UT   07 19 00.9   +26 56 56     7.990    7.008   14.1    2.0    79   20.2 
2025-06-27 00:00 UT   07 19 46.1   +26 57 18     7.989    7.003   13.4    1.9    77   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.