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	25 Jul 2026	28.1	18.122 AU	17.301 AU	18h35m	+07°25'	142.9°	1.9°	137°

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)                : 0.9638980
    q (Perihelion distance)         : 1.4236020
    i (Inclination)                 : 84.39450
    Ω (Longitude of ascending node) : 278.46760
    ω (Argument of perihelion)      : 237.85980
    L (Longitude of perihelion)     : 287.30465
    B (Latitude of perihelion)      : -57.42631
    T (Time of perihelion passage)  : 2458692.87260
    P (Orbital period in years)     : 247.62

    Epoch                           : 2026 May 29
    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
2026-07-24 00:00 UT   18 35 44.7   +07 26 41    17.284   18.114  143.8    1.9   140   28.1 
2026-07-25 00:00 UT   18 35 32.4   +07 26 08    17.294   18.118  143.3    1.9   138   28.1 
2026-07-25 17:24 UT   18 35 23.5   +07 25 43    17.301   18.122  142.9    1.9   137   28.1 
2026-07-26 00:00 UT   18 35 20.1   +07 25 33    17.304   18.123  142.7    1.9   137   28.1 
2026-07-27 00:00 UT   18 35 08.0   +07 24 57    17.315   18.128  142.2    2.0   135   28.1 
2026-07-28 00:00 UT   18 34 56.1   +07 24 19    17.325   18.133  141.6    2.0   134   28.1 
2026-07-29 00:00 UT   18 34 44.2   +07 23 40    17.337   18.137  141.0    2.0   133   28.1 
2026-07-30 00:00 UT   18 34 32.4   +07 22 60    17.348   18.142  140.4    2.0   131   28.1 
2026-07-31 00:00 UT   18 34 20.8   +07 22 18    17.359   18.147  139.8    2.1   130   28.1 
2026-08-01 00:00 UT   18 34 09.3   +07 21 35    17.371   18.152  139.2    2.1   129   28.1 
2026-08-02 00:00 UT   18 33 58.0   +07 20 50    17.383   18.156  138.5    2.1   128   28.1 
2026-08-03 00:00 UT   18 33 46.7   +07 20 04    17.395   18.161  137.9    2.1   127   28.1 
2026-08-04 00:00 UT   18 33 35.6   +07 19 17    17.408   18.166  137.2    2.2   126   28.1 

    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.