P/2017 G1 (PANSTARRS)
ephemeris date magn radius delta ra dec elong phase PA
Today20 May 202629.511.857 AU11.313 AU 20h00m-16°30'120.4°4.2°256°
Perihelion7 Aug 203520.22.510 AU3.471 AU 08h00m+17°51'15.7°6.3°272°
Nearest approach25 Feb 203619.93.046 AU2.096 AU 11h29m-04°40'160.0°6.4°314°
P/2017 G1 (PANSTARRS)- 2026-05-20
astro.vanbuitenen.nl


 
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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. The light curve is based on the absolute magnitude and slope parameter as calculated from an MPEC, or the latest values provided by the minor planet center. (13.5 + 5 log[∆] + 10.0 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 P/2017 G1 (PANSTARRS) are:

    e (Eccentricity)                : 0.6510100
    q (Perihelion distance)         : 2.5098180
    i (Inclination)                 : 5.15270
    Ω (Longitude of ascending node) : 247.11020
    ω (Argument of perihelion)      : 225.31190
    L (Longitude of perihelion)     : 292.30610
    B (Latitude of perihelion)      : -3.66084
    T (Time of perihelion passage)  : 2464546.63980
    P (Orbital period in years)     : 19.29

    Epoch                           : 2026 May 19
    Reference                       : MPEC 2026-E44

    Classification(s):              : Ecliptic; Jupiter family
    Tisserand (Jupiter)             : 2.501

Ephemerides

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2026-05-19 00:00 UT   20 00 22.0   -16 30 30    11.337   11.857  118.8    4.3   256   29.5 
2026-05-20 00:00 UT   20 00 15.3   -16 30 27    11.322   11.857  119.8    4.2   256   29.5 
2026-05-20 14:22 UT   20 00 11.1   -16 30 27    11.313   11.857  120.4    4.2   256   29.5 
2026-05-21 00:00 UT   20 00 08.2   -16 30 26    11.307   11.857  120.8    4.2   256   29.5 
2026-05-22 00:00 UT   20 00 00.8   -16 30 26    11.292   11.856  121.8    4.2   256   29.5 
2026-05-23 00:00 UT   19 59 53.0   -16 30 27    11.278   11.856  122.8    4.1   256   29.5 
2026-05-24 00:00 UT   19 59 45.0   -16 30 29    11.264   11.856  123.7    4.1   256   29.5 
2026-05-25 00:00 UT   19 59 36.6   -16 30 31    11.250   11.856  124.7    4.0   256   29.5 
2026-05-26 00:00 UT   19 59 27.9   -16 30 35    11.236   11.856  125.7    4.0   256   29.5 
2026-05-27 00:00 UT   19 59 18.9   -16 30 40    11.222   11.855  126.7    3.9   256   29.5 
2026-05-28 00:00 UT   19 59 09.6   -16 30 47    11.208   11.855  127.7    3.9   255   29.5 
2026-05-29 00:00 UT   19 58 60.0   -16 30 54    11.195   11.855  128.7    3.8   255   29.5 
2026-05-30 00:00 UT   19 58 50.1   -16 31 02    11.182   11.855  129.7    3.8   255   29.5 



    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.