C/2017 Y2 (PANSTARRS)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Perihelion	4 Nov 2020	16.8	4.621 AU	5.314 AU	17h20m	-01°47'	41.6°	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	4 Aug 2025	25.0	12.840 AU	13.312 AU	10h16m	-40°19'	60.3°	3.9°	158°

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)                : 1.0010070
            q (Perihelion distance)         : 4.6205470
            i (Inclination)                 : 128.44750
            Ω (Longitude of ascending node) : 66.02810
            ω (Argument of perihelion)      : 147.79620
            L (Longitude of perihelion)     : 87.41462
            B (Latitude of perihelion)      : 24.66935
            T (Time of perihelion passage)  : 2459158.38190

            Epoch                           : 2025 Aug 03
            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 4.01 + 5 log[∆] + 13.85 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
2025-08-04 00:00 UT   10 16 09.9   -40 19 29    13.305   12.837   60.6    3.9   158   25.0 
2025-08-04 12:19 UT   10 16 17.6   -40 19 15    13.312   12.840   60.3    3.9   158   25.0 
2025-08-05 00:00 UT   10 16 25.0   -40 19 04    13.318   12.843   60.1    3.9   159   25.0 
2025-08-06 00:00 UT   10 16 40.2   -40 18 43    13.332   12.848   59.6    3.9   160   25.0 
2025-08-07 00:00 UT   10 16 55.4   -40 18 25    13.345   12.854   59.1    3.9   161   25.0 
2025-08-08 00:00 UT   10 17 10.7   -40 18 11    13.358   12.859   58.6    3.9   161   25.0 
2025-08-09 00:00 UT   10 17 26.1   -40 18 01    13.371   12.864   58.1    3.8   162   25.0 
2025-08-10 00:00 UT   10 17 41.6   -40 17 54    13.384   12.870   57.6    3.8   163   25.0 
2025-08-11 00:00 UT   10 17 57.2   -40 17 50    13.397   12.875   57.1    3.8   164   25.0 
2025-08-12 00:00 UT   10 18 12.8   -40 17 50    13.410   12.881   56.6    3.8   165   25.0 
2025-08-13 00:00 UT   10 18 28.4   -40 17 53    13.422   12.886   56.2    3.7   166   25.0 
2025-08-14 00:00 UT   10 18 44.1   -40 17 60    13.434   12.892   55.7    3.7   167   25.0 

    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.