C/2017 Y2 (PANSTARRS)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Perihelion	4 Nov 2020	16.8	4.620 AU	5.314 AU	17h20m	-01°47'	41.7°	8.2°	68°
Nearest approach	24 May 2021	16.5	4.890 AU	3.886 AU	16h39m	-17°06'	171.3°	1.8°	243°
Today	31 Aug 2025	25.1	12.989 AU	13.628 AU	10h23m	-40°29'	49.1°	3.4°	185°

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 Y2 (PANSTARRS) are:

            e (Eccentricity)                : 1.0009690
            q (Perihelion distance)         : 4.6200200
            i (Inclination)                 : 128.44730
            Ω (Longitude of ascending node) : 66.02700
            ω (Argument of perihelion)      : 147.78920
            L (Longitude of perihelion)     : 87.41870
            B (Latitude of perihelion)      : 24.67453
            T (Time of perihelion passage)  : 2459158.36390

            Epoch                           : 2025 Aug 29
            Reference                       : MPEC 2024-DC6

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

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 (15.00 + 5 log[∆] + 10.00 log[r]), whereas the red curve is being recalculated every 6 hours based on the available COBS/MPC observations (currently 4.02 + 5 log[∆] + 13.84 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
2025-08-31 00:00 UT   10 23 14.2   -40 28 22    13.619   12.984   49.3    3.4   184   25.1 
2025-08-31 22:43 UT   10 23 29.2   -40 29 24    13.628   12.989   49.1    3.4   185   25.1 
2025-09-01 00:00 UT   10 23 30.0   -40 29 28    13.628   12.989   49.0    3.4   186   25.1 
2025-09-02 00:00 UT   10 23 45.8   -40 30 36    13.637   12.995   48.8    3.3   187   25.1 
2025-09-03 00:00 UT   10 24 01.5   -40 31 48    13.646   13.000   48.5    3.3   188   25.1 
2025-09-04 00:00 UT   10 24 17.1   -40 33 03    13.655   13.006   48.2    3.3   189   25.1 
2025-09-05 00:00 UT   10 24 32.7   -40 34 20    13.664   13.011   48.0    3.3   190   25.1 
2025-09-06 00:00 UT   10 24 48.2   -40 35 41    13.672   13.016   47.8    3.3   191   25.1 
2025-09-07 00:00 UT   10 25 03.7   -40 37 05    13.680   13.022   47.6    3.3   193   25.1 
2025-09-08 00:00 UT   10 25 19.1   -40 38 31    13.688   13.027   47.4    3.3   194   25.1 
2025-09-09 00:00 UT   10 25 34.4   -40 40 01    13.696   13.033   47.2    3.2   195   25.1 
2025-09-10 00:00 UT   10 25 49.7   -40 41 33    13.704   13.038   47.0    3.2   196   25.1 

    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.