C/2019 A9 (PANSTARRS)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Perihelion	28 Jul 2019	12.5	1.424 AU	2.133 AU	07h30m	-12°55'	34.9°	24.1°	204°
Nearest approach	5 Sep 2019	12.6	1.528 AU	1.913 AU	09h23m	-41°19'	52.6°	31.6°	209°
Today	20 Mar 2026	28.0	17.511 AU	17.716 AU	18h53m	+05°16'	76.5°	3.2°	271°

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)                : 0.9638580
    q (Perihelion distance)         : 1.4242420
    i (Inclination)                 : 84.40160
    Ω (Longitude of ascending node) : 278.47160
    ω (Argument of perihelion)      : 237.86340
    L (Longitude of perihelion)     : 287.29888
    B (Latitude of perihelion)      : -57.43094
    T (Time of perihelion passage)  : 2458692.60960
    P (Orbital period in years)     : 247.38

    Epoch                           : 2026 Mar 16
    Reference                       : MPEC 2026-E44

    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
2026-03-19 00:00 UT   18 53 15.4   +05 13 23    17.733   17.503   75.0    3.1   272   28.0 
2026-03-20 00:00 UT   18 53 18.6   +05 15 18    17.724   17.508   75.9    3.2   272   28.0 
2026-03-20 17:48 UT   18 53 20.8   +05 16 43    17.716   17.511   76.5    3.2   271   28.0 
2026-03-21 00:00 UT   18 53 21.6   +05 17 13    17.714   17.513   76.7    3.2   271   28.0 
2026-03-22 00:00 UT   18 53 24.4   +05 19 09    17.704   17.517   77.6    3.2   271   28.0 
2026-03-23 00:00 UT   18 53 26.9   +05 21 04    17.694   17.522   78.5    3.2   270   28.0 
2026-03-24 00:00 UT   18 53 29.3   +05 22 60    17.684   17.527   79.3    3.2   270   28.0 
2026-03-25 00:00 UT   18 53 31.4   +05 24 56    17.674   17.532   80.2    3.2   269   28.0 
2026-03-26 00:00 UT   18 53 33.2   +05 26 52    17.664   17.537   81.0    3.2   269   28.0 
2026-03-27 00:00 UT   18 53 34.9   +05 28 48    17.654   17.542   81.9    3.2   268   28.0 
2026-03-28 00:00 UT   18 53 36.3   +05 30 44    17.644   17.547   82.8    3.2   268   28.0 
2026-03-29 00:00 UT   18 53 37.5   +05 32 40    17.634   17.551   83.6    3.2   267   28.0 
2026-03-30 00:00 UT   18 53 38.5   +05 34 36    17.624   17.556   84.5    3.2   267   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.