C/2019 A9 (PANSTARRS)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Perihelion	28 Jul 2019	12.5	1.424 AU	2.132 AU	07h31m	-12°56'	35.0°	24.1°	204°
Nearest approach	5 Sep 2019	12.6	1.527 AU	1.913 AU	09h23m	-41°19'	52.6°	31.6°	209°
Today	23 May 2026	28.0	17.819 AU	17.150 AU	18h48m	+07°06'	130.1°	2.5°	235°

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 9.3 + 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 A9 (PANSTARRS) are:

    e (Eccentricity)                : 0.9638950
    q (Perihelion distance)         : 1.4236610
    i (Inclination)                 : 84.39550
    Ω (Longitude of ascending node) : 278.46820
    ω (Argument of perihelion)      : 237.86010
    L (Longitude of perihelion)     : 287.30380
    B (Latitude of perihelion)      : -57.42676
    T (Time of perihelion passage)  : 2458692.84830
    P (Orbital period in years)     : 247.60

    Epoch                           : 2026 May 22
    Reference                       : MPC194159

    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
2026-05-22 00:00 UT   18 49 10.0   +07 04 13    17.158   17.812  128.9    2.5   237   28.0 
2026-05-23 00:00 UT   18 48 59.5   +07 05 27    17.153   17.817  129.7    2.5   236   28.0 
2026-05-23 11:48 UT   18 48 54.3   +07 06 02    17.150   17.819  130.1    2.5   235   28.0 
2026-05-24 00:00 UT   18 48 48.9   +07 06 39    17.148   17.822  130.4    2.5   235   28.0 
2026-05-25 00:00 UT   18 48 38.2   +07 07 49    17.143   17.827  131.2    2.5   234   28.0 
2026-05-26 00:00 UT   18 48 27.3   +07 08 59    17.138   17.831  131.9    2.4   233   28.0 
2026-05-27 00:00 UT   18 48 16.2   +07 10 06    17.134   17.836  132.7    2.4   232   28.0 
2026-05-28 00:00 UT   18 48 05.1   +07 11 12    17.129   17.841  133.4    2.4   231   28.0 
2026-05-29 00:00 UT   18 47 53.7   +07 12 17    17.125   17.846  134.1    2.3   230   28.0 
2026-05-30 00:00 UT   18 47 42.3   +07 13 20    17.121   17.851  134.8    2.3   229   28.0 
2026-05-31 00:00 UT   18 47 30.7   +07 14 21    17.118   17.855  135.5    2.3   228   28.0 
2026-06-01 00:00 UT   18 47 19.0   +07 15 21    17.114   17.860  136.2    2.3   227   28.0 
2026-06-02 00:00 UT   18 47 07.2   +07 16 19    17.111   17.865  136.9    2.2   226   28.0 

    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.