15P/Finlay
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Today	10 Nov 2025	29.3	5.595 AU	6.454 AU	13h15m	-08°11'	27.6°	4.7°	292°
Perihelion	9 Feb 2028	12.1	0.997 AU	1.855 AU	22h51m	-08°07'	20.9°	20.6°	70°
Nearest approach	17 Feb 2028	12.1	1.003 AU	1.850 AU	23h22m	-04°09'	21.9°	21.6°	67°

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. This lightcurve is being recalculated every 6 hours based on the available COBS/MPC observations (currently 10.7 + 5 log[∆] + 19.4 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 15P/Finlay are:

    e (Eccentricity)                : 0.7159650
    q (Perihelion distance)         : 0.9973380
    i (Inclination)                 : 6.78530
    Ω (Longitude of ascending node) : 13.74900
    ω (Argument of perihelion)      : 347.85890
    L (Longitude of perihelion)     : 1.69044
    B (Latitude of perihelion)      : -1.42390
    T (Time of perihelion passage)  : 2461811.35310
    P (Orbital period in years)     : 6.58

    Epoch                           : 2025 Nov 09
    Reference                       : MPEC 2022-ED3

    Classification(s):              : Ecliptic; Jupiter family
    Tisserand (Jupiter)             : 2.621

Ephemerides

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2025-11-09 00:00 UT   13 14 20.5   -08 05 09     6.470    5.599   26.3    4.5   292   29.3 
2025-11-10 00:00 UT   13 14 59.1   -08 09 19     6.460    5.596   27.1    4.6   292   29.3 
2025-11-10 13:53 UT   13 15 21.3   -08 11 43     6.454    5.595   27.6    4.7   292   29.3 
2025-11-11 00:00 UT   13 15 37.5   -08 13 28     6.450    5.594   27.9    4.8   292   29.3 
2025-11-12 00:00 UT   13 16 15.7   -08 17 36     6.439    5.592   28.8    4.9   292   29.2 
2025-11-13 00:00 UT   13 16 53.9   -08 21 43     6.429    5.589   29.6    5.0   292   29.2 
2025-11-14 00:00 UT   13 17 31.8   -08 25 49     6.418    5.587   30.4    5.1   292   29.2 
2025-11-15 00:00 UT   13 18 09.6   -08 29 53     6.407    5.585   31.3    5.3   292   29.2 
2025-11-16 00:00 UT   13 18 47.2   -08 33 57     6.395    5.582   32.1    5.4   292   29.2 
2025-11-17 00:00 UT   13 19 24.7   -08 37 59     6.384    5.580   33.0    5.5   292   29.2 
2025-11-18 00:00 UT   13 20 02.0   -08 41 60     6.372    5.578   33.8    5.7   292   29.2 
2025-11-19 00:00 UT   13 20 39.0   -08 45 59     6.360    5.575   34.6    5.8   292   29.2 
2025-11-20 00:00 UT   13 21 15.9   -08 49 57     6.348    5.573   35.5    5.9   292   29.2 

    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.