C/2013 X1 (PANSTARRS)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Perihelion	23 Apr 2016	9.4	1.314 AU	1.934 AU	23h36m	+00°31'	38.9°	28.8°	250°
Nearest approach	22 Jun 2016	7.8	1.587 AU	0.628 AU	19h54m	-45°57'	148.8°	19.4°	307°
Today	18 Dec 2025	27.6	24.290 AU	24.239 AU	11h22m	-08°07'	91.8°	2.3°	294°

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 6.8 + 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/2013 X1 (PANSTARRS) are:

    e (Eccentricity)                : 1.0009490
    q (Perihelion distance)         : 1.3137500
    i (Inclination)                 : 163.07720
    Ω (Longitude of ascending node) : 132.04470
    ω (Argument of perihelion)      : 165.48360
    L (Longitude of perihelion)     : 145.95744
    B (Latitude of perihelion)      : 4.18413
    T (Time of perihelion passage)  : 2457502.08000

    Epoch                           : 2025 Dec 17
    Reference                       : MPC111767

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

Ephemerides

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2025-12-17 00:00 UT   11 22 45.1   -08 06 42    24.258   24.283   90.2    2.3   294   27.6 
2025-12-18 00:00 UT   11 22 43.5   -08 07 01    24.246   24.288   91.2    2.3   294   27.6 
2025-12-18 12:49 UT   11 22 42.6   -08 07 11    24.239   24.290   91.8    2.3   294   27.6 
2025-12-19 00:00 UT   11 22 41.8   -08 07 19    24.233   24.292   92.2    2.3   294   27.6 
2025-12-20 00:00 UT   11 22 39.9   -08 07 36    24.221   24.297   93.2    2.3   294   27.6 
2025-12-21 00:00 UT   11 22 37.8   -08 07 52    24.209   24.302   94.3    2.3   294   27.6 
2025-12-22 00:00 UT   11 22 35.6   -08 08 06    24.196   24.307   95.3    2.3   295   27.6 
2025-12-23 00:00 UT   11 22 33.2   -08 08 20    24.184   24.312   96.3    2.3   295   27.6 
2025-12-24 00:00 UT   11 22 30.7   -08 08 32    24.172   24.316   97.3    2.3   295   27.6 
2025-12-25 00:00 UT   11 22 28.0   -08 08 44    24.159   24.321   98.3    2.3   295   27.6 
2025-12-26 00:00 UT   11 22 25.1   -08 08 54    24.147   24.326   99.3    2.3   295   27.6 
2025-12-27 00:00 UT   11 22 22.1   -08 09 03    24.135   24.331  100.3    2.3   296   27.6 
2025-12-28 00:00 UT   11 22 18.9   -08 09 11    24.123   24.336  101.3    2.3   296   27.6 

    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.