Skip Navigation Links

C/2017 E3 (PANSTARRS)
ephemeris date magn radius delta ra dec elong phase PA
Nearest approach25 Apr 201716.15.907 AU5.046 AU 12h45m-41°47'146.0°5.5°39°
Perihelion6 Jun 201716.25.899 AU5.297 AU 12h37m-33°55'122.1°8.4°97°
Today9 Jul 202627.320.265 AU19.970 AU 19h10m+52°12'105.4°2.8°180°
C/2017 E3 (PANSTARRS)- 2026-07-09
astro.vanbuitenen.nl


 
-1 month
-1 week
-1 day
Now
+1 day
+1 week
+1 month

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 .9 + 5 log[∆] + 15.2 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 E3 (PANSTARRS) are: 

    e (Eccentricity)                : 1.0042700
    q (Perihelion distance)         : 5.8989770
    i (Inclination)                 : 70.66580
    Ω (Longitude of ascending node) : 220.73140
    ω (Argument of perihelion)      : 334.15120
    L (Longitude of perihelion)     : 211.61893
    B (Latitude of perihelion)      : -24.29338
    T (Time of perihelion passage)  : 2457911.48910

    Epoch                           : 2026 Jul 08
    Reference                       : MPEC 2026-L50

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

Ephemerides

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2026-07-08 00:00 UT   19 11 11.9   +52 12 12    19.967   20.259  105.3    2.8   181   27.3 
2026-07-09 00:00 UT   19 10 56.0   +52 12 18    19.970   20.264  105.4    2.8   180   27.3 
2026-07-09 05:17 UT   19 10 52.5   +52 12 19    19.970   20.265  105.4    2.8   180   27.3 
2026-07-10 00:00 UT   19 10 40.1   +52 12 21    19.972   20.268  105.5    2.8   179   27.3 
2026-07-11 00:00 UT   19 10 24.2   +52 12 21    19.975   20.273  105.6    2.8   178   27.3 
2026-07-12 00:00 UT   19 10 08.3   +52 12 19    19.978   20.277  105.7    2.8   177   27.3 
2026-07-13 00:00 UT   19 09 52.5   +52 12 13    19.981   20.282  105.8    2.8   176   27.3 
2026-07-14 00:00 UT   19 09 36.6   +52 12 04    19.984   20.286  105.9    2.8   175   27.3 
2026-07-15 00:00 UT   19 09 20.9   +52 11 52    19.987   20.291  106.0    2.8   174   27.3 
2026-07-16 00:00 UT   19 09 05.1   +52 11 37    19.991   20.296  106.0    2.8   173   27.3 
2026-07-17 00:00 UT   19 08 49.4   +52 11 19    19.994   20.300  106.1    2.8   171   27.3 
2026-07-18 00:00 UT   19 08 33.8   +52 10 58    19.997   20.305  106.2    2.8   170   27.3 
2026-07-19 00:00 UT   19 08 18.2   +52 10 35    20.001   20.309  106.3    2.8   169   27.3 




    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.

Privacy policy