C/2019 A5 (PANSTARRS)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Nearest approach	13 Feb 2019	21.2	6.349 AU	5.390 AU	09h14m	+00°46'	165.0°	2.3°	33°
Perihelion	7 Jun 2019	21.7	6.315 AU	6.750 AU	09h12m	+12°22'	60.7°	8.1°	109°
Today	29 Dec 2025	26.5	13.462 AU	13.904 AU	17h54m	+37°32'	61.5°	3.7°	350°

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. (9.5 + 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/2019 A5 (PANSTARRS) are:

    e (Eccentricity)                : 0.7066260
    q (Perihelion distance)         : 6.3152070
    i (Inclination)                 : 67.55470
    Ω (Longitude of ascending node) : 146.49250
    ω (Argument of perihelion)      : 355.87340
    L (Longitude of perihelion)     : 144.91463
    B (Latitude of perihelion)      : -3.81351
    T (Time of perihelion passage)  : 2458642.00110
    P (Orbital period in years)     : 99.87

    Epoch                           : 2025 Dec 28
    Reference                       : MPEC 2021-P47

    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
2025-12-28 00:00 UT   17 53 59.5   +37 32 48    13.900   13.457   61.3    3.7   351   26.5 
2025-12-29 00:00 UT   17 54 25.6   +37 32 51    13.903   13.460   61.4    3.7   350   26.5 
2025-12-29 14:26 UT   17 54 41.2   +37 32 55    13.904   13.462   61.5    3.7   350   26.5 
2025-12-30 00:00 UT   17 54 51.6   +37 32 58    13.905   13.464   61.5    3.7   349   26.5 
2025-12-31 00:00 UT   17 55 17.6   +37 33 08    13.907   13.467   61.6    3.7   348   26.5 
2026-01-01 00:00 UT   17 55 43.4   +37 33 22    13.909   13.471   61.7    3.7   347   26.5 
2026-01-02 00:00 UT   17 56 09.3   +37 33 40    13.911   13.474   61.8    3.7   346   26.5 
2026-01-03 00:00 UT   17 56 35.0   +37 34 00    13.913   13.478   61.9    3.7   345   26.5 
2026-01-04 00:00 UT   17 57 00.6   +37 34 25    13.915   13.481   62.0    3.7   344   26.5 
2026-01-05 00:00 UT   17 57 26.2   +37 34 53    13.916   13.485   62.1    3.7   343   26.5 
2026-01-06 00:00 UT   17 57 51.6   +37 35 24    13.918   13.488   62.3    3.7   342   26.5 
2026-01-07 00:00 UT   17 58 17.0   +37 35 59    13.919   13.492   62.4    3.7   341   26.5 
2026-01-08 00:00 UT   17 58 42.2   +37 36 37    13.920   13.496   62.6    3.7   340   26.5 

    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.