C/2013 X1 (PANSTARRS)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Perihelion	19 Apr 2016	9.5	1.326 AU	1.984 AU	23h29m	-00°15'	36.9°	27.0°	251°
Nearest approach	21 Jun 2016	8.0	1.614 AU	0.656 AU	19h47m	-45°48'	148.9°	19.0°	307°
Today	21 Oct 2025	27.6	23.998 AU	24.800 AU	11h19m	-07°25'	35.5°	1.4°	278°

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)                : 1.0005450
    q (Perihelion distance)         : 1.3256690
    i (Inclination)                 : 163.19370
    Ω (Longitude of ascending node) : 131.57360
    ω (Argument of perihelion)      : 165.21110
    L (Longitude of perihelion)     : 145.75685
    B (Latitude of perihelion)      : 4.23254
    T (Time of perihelion passage)  : 2457497.95670

    Epoch                           : 2021 Jun 11
    Reference                       : MPC111767

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

Ephemerides

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2025-10-20 00:00 UT   11 19 41.3   -07 24 18    24.807   23.992   34.3    1.3   277   27.6 
2025-10-21 00:00 UT   11 19 47.7   -07 25 13    24.802   23.996   35.3    1.4   278   27.6 
2025-10-21 07:13 UT   11 19 49.5   -07 25 30    24.800   23.998   35.5    1.4   278   27.6 
2025-10-22 00:00 UT   11 19 53.9   -07 26 08    24.797   24.001   36.2    1.4   278   27.6 
2025-10-23 00:00 UT   11 20 00.0   -07 27 03    24.792   24.006   37.1    1.4   279   27.6 
2025-10-24 00:00 UT   11 20 06.1   -07 27 58    24.786   24.011   38.0    1.5   279   27.6 
2025-10-25 00:00 UT   11 20 12.0   -07 28 53    24.781   24.016   38.9    1.5   280   27.6 
2025-10-26 00:00 UT   11 20 17.9   -07 29 47    24.775   24.021   39.9    1.5   280   27.6 
2025-10-27 00:00 UT   11 20 23.6   -07 30 41    24.769   24.025   40.8    1.5   281   27.6 
2025-10-28 00:00 UT   11 20 29.2   -07 31 35    24.762   24.030   41.7    1.6   281   27.6 
2025-10-29 00:00 UT   11 20 34.8   -07 32 29    24.756   24.035   42.7    1.6   282   27.6 
2025-10-30 00:00 UT   11 20 40.2   -07 33 22    24.749   24.040   43.6    1.6   282   27.6 
2025-10-31 00:00 UT   11 20 45.5   -07 34 15    24.742   24.045   44.5    1.7   282   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.