C/2016 R2 (PANSTARRS)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Nearest approach	22 Dec 2017	11.6	2.987 AU	2.067 AU	04h33m	+10°23'	155.0°	8.0°	56°
Perihelion	12 May 2018	11.9	2.597 AU	3.293 AU	05h34m	+44°52'	39.6°	14.4°	59°
Today	8 May 2026	26.4	20.103 AU	19.229 AU	17h08m	-15°12'	149.1°	1.5°	262°

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 4.3 + 5 log[∆] + 12.0 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/2016 R2 (PANSTARRS) are:

    e (Eccentricity)                : 0.9955560
    q (Perihelion distance)         : 2.5967770
    i (Inclination)                 : 58.38740
    Ω (Longitude of ascending node) : 80.49100
    ω (Argument of perihelion)      : 33.17350
    L (Longitude of perihelion)     : 99.40570
    B (Latitude of perihelion)      : 27.77377
    T (Time of perihelion passage)  : 2458250.54140
    P (Orbital period in years)     : 14125.08

    Epoch                           : 2026 May 07
    Reference                       : MPEC 2026-E44

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

Ephemerides

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2026-05-07 00:00 UT   17 08 25.8   -15 12 28    19.234   20.096  147.8    1.5   263   26.4 
2026-05-08 00:00 UT   17 08 15.7   -15 12 20    19.231   20.101  148.8    1.5   262   26.4 
2026-05-08 08:27 UT   17 08 12.1   -15 12 18    19.229   20.103  149.1    1.5   262   26.4 
2026-05-09 00:00 UT   17 08 05.5   -15 12 13    19.227   20.106  149.8    1.4   262   26.4 
2026-05-10 00:00 UT   17 07 55.2   -15 12 05    19.224   20.111  150.7    1.4   261   26.4 
2026-05-11 00:00 UT   17 07 44.8   -15 11 58    19.221   20.116  151.7    1.4   261   26.4 
2026-05-12 00:00 UT   17 07 34.3   -15 11 51    19.218   20.121  152.7    1.3   260   26.4 
2026-05-13 00:00 UT   17 07 23.7   -15 11 44    19.215   20.126  153.6    1.3   260   26.4 
2026-05-14 00:00 UT   17 07 13.0   -15 11 37    19.213   20.131  154.6    1.2   259   26.4 
2026-05-15 00:00 UT   17 07 02.1   -15 11 31    19.211   20.136  155.6    1.2   258   26.4 
2026-05-16 00:00 UT   17 06 51.2   -15 11 25    19.209   20.141  156.5    1.1   257   26.4 
2026-05-17 00:00 UT   17 06 40.3   -15 11 19    19.208   20.146  157.5    1.1   256   26.4 
2026-05-18 00:00 UT   17 06 29.2   -15 11 13    19.207   20.151  158.4    1.1   256   26.4 

    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.