C/2017 T1 (Heinze)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Nearest approach	3 Jan 2018	10.0	1.150 AU	0.226 AU	06h16m	+69°12'	133.2°	38.6°	167°
Perihelion	20 Feb 2018	10.7	0.586 AU	1.233 AU	21h33m	+15°06'	27.9°	52.2°	338°
Today	15 Nov 2025	33.1	21.408 AU	21.650 AU	08h17m	-80°08'	74.5°	2.6°	289°

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 12.6 + 5 log[∆] + 10.4 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 C/2017 T1 (Heinze) are:

    e (Eccentricity)                : 0.9999450
    q (Perihelion distance)         : 0.5860040
    i (Inclination)                 : 96.93720
    Ω (Longitude of ascending node) : 102.65210
    ω (Argument of perihelion)      : 97.04450
    L (Longitude of perihelion)     : 146.99755
    B (Latitude of perihelion)      : 80.12545
    T (Time of perihelion passage)  : 2458170.12690

    Epoch                           : 2023 Apr 14
    Reference                       : MPC114600

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

Ephemerides

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2025-11-14 00:00 UT   08 18 05.2   -80 06 02    21.643   21.402   74.6    2.6   287   33.1 
2025-11-15 00:00 UT   08 17 41.3   -80 08 28    21.650   21.408   74.5    2.6   289   33.1 
2025-11-15 00:37 UT   08 17 40.6   -80 08 32    21.650   21.408   74.5    2.6   289   33.1 
2025-11-16 00:00 UT   08 17 16.2   -80 10 54    21.656   21.413   74.4    2.6   290   33.1 
2025-11-17 00:00 UT   08 16 49.8   -80 13 18    21.663   21.418   74.4    2.5   291   33.1 
2025-11-18 00:00 UT   08 16 22.3   -80 15 42    21.669   21.423   74.3    2.5   292   33.2 
2025-11-19 00:00 UT   08 15 53.5   -80 18 04    21.675   21.428   74.2    2.5   293   33.2 
2025-11-20 00:00 UT   08 15 23.4   -80 20 24    21.682   21.434   74.2    2.5   294   33.2 
2025-11-21 00:00 UT   08 14 52.2   -80 22 44    21.688   21.439   74.1    2.5   295   33.2 
2025-11-22 00:00 UT   08 14 19.7   -80 25 01    21.694   21.444   74.0    2.5   297   33.2 
2025-11-23 00:00 UT   08 13 45.9   -80 27 18    21.700   21.449   74.0    2.5   298   33.2 
2025-11-24 00:00 UT   08 13 11.0   -80 29 32    21.706   21.454   73.9    2.5   299   33.2 
2025-11-25 00:00 UT   08 12 34.8   -80 31 45    21.712   21.459   73.9    2.5   300   33.2 

    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.