C/2025 F1 (ATLAS)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Nearest approach	27 Mar 2025	18.7	1.142 AU	1.082 AU	04h19m	-34°27'	66.5°	53.2°	111°
Perihelion	20 Apr 2025	18.9	1.070 AU	1.328 AU	05h22m	+03°47'	52.4°	48.1°	102°
Today	28 Aug 2025	23.6	2.244 AU	2.607 AU	09h31m	+66°43'	58.1°	22.5°	343°

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/2025 F1 (ATLAS) are:

            e (Eccentricity)                : 0.9962730
            q (Perihelion distance)         : 1.0699220
            i (Inclination)                 : 109.23720
            Ω (Longitude of ascending node) : 122.70550
            ω (Argument of perihelion)      : 334.22600
            L (Longitude of perihelion)     : 131.74506
            B (Latitude of perihelion)      : -24.23896
            T (Time of perihelion passage)  : 2460785.97010
            P (Orbital period in years)     : 4863.95

            Epoch                           : 2025 Aug 27
            Reference                       : MPC185661

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

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 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. (18.00 + 5 log[∆] + 10.00 log[r]).

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
2025-08-28 00:00 UT   09 27 38.1   +66 25 30     2.607    2.233   57.5   22.4   343   23.6 
2025-08-28 22:31 UT   09 31 11.5   +66 43 60     2.607    2.244   58.1   22.5   343   23.6 
2025-08-29 00:00 UT   09 31 25.7   +66 45 13     2.607    2.245   58.1   22.5   343   23.6 
2025-08-30 00:00 UT   09 35 18.4   +67 04 51     2.608    2.256   58.8   22.5   343   23.6 
2025-08-31 00:00 UT   09 39 16.6   +67 24 25     2.608    2.268   59.4   22.5   343   23.6 
2025-09-01 00:00 UT   09 43 20.5   +67 43 54     2.608    2.280   60.1   22.6   344   23.7 
2025-09-02 00:00 UT   09 47 30.1   +68 03 16     2.608    2.292   60.8   22.6   344   23.7 
2025-09-03 00:00 UT   09 51 45.9   +68 22 32     2.608    2.303   61.4   22.6   344   23.7 
2025-09-04 00:00 UT   09 56 08.0   +68 41 41     2.609    2.315   62.1   22.6   344   23.7 
2025-09-05 00:00 UT   10 00 36.7   +69 00 41     2.609    2.327   62.7   22.7   345   23.7 
2025-09-06 00:00 UT   10 05 12.1   +69 19 32     2.609    2.338   63.4   22.7   345   23.8 
2025-09-07 00:00 UT   10 09 54.7   +69 38 12     2.610    2.350   64.0   22.7   346   23.8 

    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.