C/2015 V4 (PANSTARRS)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Perihelion	31 Aug 2016	19.8	5.431 AU	6.181 AU	09h10m	-23°40'	38.8°	6.7°	216°
Nearest approach	28 Feb 2017	19.3	5.546 AU	4.715 AU	09h52m	-25°51'	143.9°	6.0°	23°
Today	17 Apr 2026	26.9	17.073 AU	16.680 AU	17h08m	+38°03'	111.4°	3.1°	236°

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. (8.5 + 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 C/2015 V4 (PANSTARRS) are:

    e (Eccentricity)                : 0.7055060
    q (Perihelion distance)         : 5.4310620
    i (Inclination)                 : 60.75820
    Ω (Longitude of ascending node) : 179.80320
    ω (Argument of perihelion)      : 306.77950
    L (Longitude of perihelion)     : 146.63963
    B (Latitude of perihelion)      : -44.33705
    T (Time of perihelion passage)  : 2457631.56430
    P (Orbital period in years)     : 79.20

    Epoch                           : 2026 Apr 16
    Reference                       : MPEC 2026-E44

    Classification(s):              : Nearly isotropic; Returning (a < 10000 AU); Halley type (P < 200 years)

Ephemerides

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2026-04-16 00:00 UT   17 08 52.8   +37 58 54    16.685   17.068  110.9    3.1   238   26.9 
2026-04-17 00:00 UT   17 08 45.1   +38 01 31    16.682   17.071  111.2    3.1   237   26.9 
2026-04-17 13:51 UT   17 08 40.6   +38 03 01    16.680   17.073  111.4    3.1   236   26.9 
2026-04-18 00:00 UT   17 08 37.1   +38 04 06    16.679   17.074  111.6    3.1   236   26.9 
2026-04-19 00:00 UT   17 08 28.9   +38 06 40    16.677   17.077  111.9    3.1   235   26.9 
2026-04-20 00:00 UT   17 08 20.5   +38 09 11    16.675   17.081  112.2    3.1   234   26.9 
2026-04-21 00:00 UT   17 08 11.8   +38 11 41    16.672   17.084  112.6    3.1   233   26.9 
2026-04-22 00:00 UT   17 08 02.8   +38 14 09    16.670   17.087  112.9    3.1   232   26.9 
2026-04-23 00:00 UT   17 07 53.6   +38 16 34    16.668   17.090  113.2    3.1   231   26.9 
2026-04-24 00:00 UT   17 07 44.2   +38 18 57    16.667   17.093  113.5    3.1   230   26.9 
2026-04-25 00:00 UT   17 07 34.6   +38 21 19    16.665   17.096  113.8    3.1   229   26.9 
2026-04-26 00:00 UT   17 07 24.7   +38 23 37    16.663   17.099  114.1    3.1   227   26.9 
2026-04-27 00:00 UT   17 07 14.6   +38 25 54    16.662   17.102  114.4    3.1   226   26.9 

    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.