C/2017 T2 (PANSTARRS)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Nearest approach	28 Dec 2019	9.8	2.331 AU	1.522 AU	03h34m	+53°08'	135.9°	17.1°	115°
Perihelion	6 May 2020	8.6	1.604 AU	1.697 AU	07h00m	+75°41'	67.2°	35.4°	67°
Today	31 May 2025	21.8	15.133 AU	14.529 AU	19h53m	-67°44'	124.9°	3.1°	300°

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/2017 T2 (PANSTARRS) are:

            e (Eccentricity)                : 0.9989930
            q (Perihelion distance)         : 1.6040210
            i (Inclination)                 : 57.28480
            Ω (Longitude of ascending node) : 64.43750
            ω (Argument of perihelion)      : 92.77990
            L (Longitude of perihelion)     : -20.42870
            B (Latitude of perihelion)      : 57.17999
            T (Time of perihelion passage)  : 2458975.52340
            P (Orbital period in years)     : 63572.73

            Epoch                           : 2025 May 30
            Reference                       : MPEC 2024-A43

            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 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 (5.00 + 5 log[∆] + 10.00 log[r]), whereas the red curve is being recalculated every 6 hours based on the available COBS/MPC observations (currently 5.69 + 5 log[∆] + 8.76 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
2025-05-31 00:00 UT   19 54 00.2   -67 42 39    14.530   15.129  124.6    3.2   299   21.8 
2025-05-31 17:13 UT   19 53 42.8   -67 44 33    14.529   15.133  124.9    3.1   300   21.8 
2025-06-01 00:00 UT   19 53 35.8   -67 45 18    14.529   15.134  125.1    3.1   300   21.8 
2025-06-02 00:00 UT   19 53 10.7   -67 47 55    14.528   15.140  125.5    3.1   302   21.8 
2025-06-03 00:00 UT   19 52 45.1   -67 50 31    14.528   15.146  126.0    3.1   303   21.8 
2025-06-04 00:00 UT   19 52 18.9   -67 53 04    14.527   15.152  126.4    3.1   304   21.8 
2025-06-05 00:00 UT   19 51 52.1   -67 55 35    14.527   15.158  126.9    3.1   305   21.8 
2025-06-06 00:00 UT   19 51 24.7   -67 58 04    14.527   15.164  127.3    3.1   306   21.9 
2025-06-07 00:00 UT   19 50 56.8   -68 00 31    14.527   15.170  127.7    3.0   308   21.9 
2025-06-08 00:00 UT   19 50 28.3   -68 02 56    14.528   15.176  128.1    3.0   309   21.9 
2025-06-09 00:00 UT   19 49 59.3   -68 05 18    14.528   15.182  128.5    3.0   310   21.9 
2025-06-10 00:00 UT   19 49 29.8   -68 07 38    14.529   15.187  128.9    3.0   311   21.9 

    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.