107P/Wilson-Harrington
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Today	26 Dec 2024	25.6	4.252 AU	4.410 AU	13h11m	-10°26'	74.4°	12.9°	292°
Perihelion	25 Nov 2026	16.0	0.969 AU	0.988 AU	20h12m	-17°08'	58.7°	60.6°	76°
Nearest approach	21 Dec 2026	16.1	1.032 AU	0.918 AU	22h22m	-07°28'	65.6°	60.2°	68°

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 107P/Wilson-Harrington are:

            e (Eccentricity)                : 0.6311320
            q (Perihelion distance)         : 0.9685440
            i (Inclination)                 : 2.79860
            Ω (Longitude of ascending node) : 266.72910
            ω (Argument of perihelion)      : 95.52230
            L (Longitude of perihelion)     : 182.25795
            B (Latitude of perihelion)      : 2.78560
            T (Time of perihelion passage)  : 2461370.01100
            P (Orbital period in years)     : 4.25

            Epoch                           : 2024 Dec 25
            Reference                       : MPEC 2015-M77

            Classification(s):              : Ecliptic; Encke type; Active asteroid
            Tisserand (Jupiter)             : 3.082
        

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 is based on the absolute magnitude and slope parameter as calculated from the original MPEC, or the latest values provided by the MPC (18.50 + 5 log[∆] + 10.00 log[r]), whereas the red curve is being recalculated every 6 hours based on the available COBS/MPC observations (currently 16.13 + 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
2024-12-26 00:00 UT   13 11 14.6   -10 24 47     4.417    4.252   74.0   12.8   292   25.6 
2024-12-26 10:49 UT   13 11 27.3   -10 26 19     4.410    4.252   74.4   12.9   292   25.6 
2024-12-27 00:00 UT   13 11 42.5   -10 28 10     4.401    4.251   74.9   12.9   292   25.6 
2024-12-28 00:00 UT   13 12 09.8   -10 31 29     4.384    4.251   75.8   13.0   292   25.6 
2024-12-29 00:00 UT   13 12 36.5   -10 34 45     4.367    4.250   76.7   13.0   292   25.6 
2024-12-30 00:00 UT   13 13 02.5   -10 37 57     4.351    4.249   77.6   13.1   292   25.6 
2024-12-31 00:00 UT   13 13 27.7   -10 41 05     4.334    4.248   78.5   13.1   292   25.6 
2025-01-01 00:00 UT   13 13 52.3   -10 44 09     4.317    4.247   79.4   13.2   292   25.6 
2025-01-02 00:00 UT   13 14 16.2   -10 47 09     4.300    4.246   80.3   13.2   292   25.6 
2025-01-03 00:00 UT   13 14 39.4   -10 50 06     4.283    4.246   81.2   13.2   292   25.6 
2025-01-04 00:00 UT   13 15 01.9   -10 52 58     4.266    4.245   82.1   13.3   292   25.6 
2025-01-05 00:00 UT   13 15 23.6   -10 55 46     4.249    4.244   83.0   13.3   292   25.6 

    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.