A/2025 A1
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Today	28 Jan 2026	19.0	6.130 AU	5.184 AU	08h38m	+35°43'	162.4°	2.8°	176°
Nearest approach	5 Mar 2027	18.6	5.340 AU	4.514 AU	12h13m	+39°26'	143.1°	6.4°	210°
Perihelion	13 Mar 2027	18.6	5.339 AU	4.521 AU	12h10m	+39°58'	142.0°	6.6°	195°

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=11.20; 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/2025 A1 are:

    e (Eccentricity)                : 1.0016300
    q (Perihelion distance)         : 5.3393290
    i (Inclination)                 : 33.41980
    Ω (Longitude of ascending node) : 101.32730
    ω (Argument of perihelion)      : 68.20100
    L (Longitude of perihelion)     : 165.72449
    B (Latitude of perihelion)      : 30.75613
    T (Time of perihelion passage)  : 2461478.35560

    Epoch                           : 2026 Jan 27
    Reference                       : MPEC 2026-A90

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

Ephemerides

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2026-01-27 00:00 UT   08 38 52.2   +35 36 26     5.187    6.136  163.0    2.7   182   19.0 
2026-01-28 00:00 UT   08 38 25.9   +35 40 60     5.185    6.132  162.7    2.7   178   19.0 
2026-01-28 13:19 UT   08 38 11.3   +35 43 30     5.184    6.130  162.4    2.8   176   19.0 
2026-01-29 00:00 UT   08 37 59.5   +35 45 30     5.183    6.129  162.3    2.8   175   19.0 
2026-01-30 00:00 UT   08 37 33.2   +35 49 56     5.182    6.125  161.8    2.9   171   19.0 
2026-01-31 00:00 UT   08 37 06.8   +35 54 19     5.180    6.122  161.3    3.0   168   19.0 
2026-02-01 00:00 UT   08 36 40.4   +35 58 37     5.179    6.118  160.8    3.0   165   19.0 
2026-02-02 00:00 UT   08 36 14.0   +36 02 51     5.179    6.115  160.2    3.1   162   19.0 
2026-02-03 00:00 UT   08 35 47.7   +36 07 01     5.178    6.111  159.5    3.2   160   19.0 
2026-02-04 00:00 UT   08 35 21.5   +36 11 07     5.178    6.108  158.8    3.3   157   19.0 
2026-02-05 00:00 UT   08 34 55.3   +36 15 08     5.178    6.104  158.1    3.4   155   19.0 
2026-02-06 00:00 UT   08 34 29.3   +36 19 06     5.179    6.101  157.4    3.6   152   19.0 
2026-02-07 00:00 UT   08 34 03.4   +36 22 58     5.179    6.097  156.6    3.7   150   19.0 

    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.