C/2016 R2 (PANSTARRS)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Nearest approach	22 Dec 2017	11.6	2.986 AU	2.065 AU	04h33m	+10°20'	154.9°	8.0°	56°
Perihelion	12 May 2018	11.9	2.595 AU	3.291 AU	05h34m	+44°52'	39.6°	14.4°	59°
Today	2 Feb 2026	26.3	19.624 AU	20.166 AU	17h10m	-15°22'	55.4°	2.4°	280°

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)                : 0.9955110
    q (Perihelion distance)         : 2.5947560
    i (Inclination)                 : 58.37910
    Ω (Longitude of ascending node) : 80.47170
    ω (Argument of perihelion)      : 33.17900
    L (Longitude of perihelion)     : 99.39422
    B (Latitude of perihelion)      : 27.77551
    T (Time of perihelion passage)  : 2458250.51850
    P (Orbital period in years)     : 13896.98

    Epoch                           : 2026 Feb 01
    Reference                       : MPEC 2021-N06

    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
2026-02-01 00:00 UT   17 10 35.9   -15 22 01    20.178   19.618   54.1    2.3   280   26.3 
2026-02-02 00:00 UT   17 10 43.8   -15 22 09    20.169   19.623   55.1    2.4   280   26.3 
2026-02-02 07:43 UT   17 10 46.3   -15 22 11    20.166   19.624   55.4    2.4   280   26.3 
2026-02-03 00:00 UT   17 10 51.5   -15 22 16    20.160   19.628   56.1    2.4   280   26.3 
2026-02-04 00:00 UT   17 10 59.0   -15 22 24    20.151   19.633   57.0    2.4   280   26.3 
2026-02-05 00:00 UT   17 11 06.4   -15 22 30    20.142   19.638   58.0    2.4   280   26.3 
2026-02-06 00:00 UT   17 11 13.6   -15 22 36    20.132   19.643   59.0    2.5   279   26.3 
2026-02-07 00:00 UT   17 11 20.6   -15 22 42    20.123   19.648   60.0    2.5   279   26.3 
2026-02-08 00:00 UT   17 11 27.4   -15 22 47    20.113   19.653   60.9    2.5   279   26.3 
2026-02-09 00:00 UT   17 11 34.0   -15 22 52    20.103   19.658   61.9    2.5   279   26.3 
2026-02-10 00:00 UT   17 11 40.5   -15 22 57    20.093   19.663   62.9    2.6   279   26.3 
2026-02-11 00:00 UT   17 11 46.8   -15 23 01    20.083   19.668   63.9    2.6   279   26.3 
2026-02-12 00:00 UT   17 11 52.9   -15 23 04    20.072   19.673   64.8    2.6   278   26.3 

    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.