C/2019 D1 (Flewelling)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Perihelion	7 May 2019	14.7	1.592 AU	1.646 AU	22h03m	+21°04'	68.9°	36.3°	259°
Nearest approach	10 Sep 2019	17.4	2.290 AU	1.567 AU	01h13m	+44°07'	124.1°	21.3°	217°
Today	4 Nov 2026	40.0	19.706 AU	19.048 AU	05h51m	+02°08'	130.5°	2.2°	288°

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 9.9 + 5 log[∆] + 18.4 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 D1 (Flewelling) are:

    e (Eccentricity)                : 0.9881120
    q (Perihelion distance)         : 1.5915730
    i (Inclination)                 : 34.05000
    Ω (Longitude of ascending node) : 231.71940
    ω (Argument of perihelion)      : 70.64420
    L (Longitude of perihelion)     : 298.74340
    B (Latitude of perihelion)      : 31.88857
    T (Time of perihelion passage)  : 2458611.30140
    P (Orbital period in years)     : 1549.09

    Epoch                           : 2026 May 29
    Reference                       : MPC194160

    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
2026-11-03 00:00 UT   05 51 15.9   +02 09 40    19.058   19.698  129.1    2.2   287   40.0 
2026-11-04 00:00 UT   05 51 08.1   +02 08 42    19.051   19.703  130.0    2.2   288   40.0 
2026-11-04 12:41 UT   05 51 04.0   +02 08 11    19.048   19.706  130.5    2.2   288   40.0 
2026-11-05 00:00 UT   05 51 00.2   +02 07 44    19.045   19.708  130.9    2.2   289   40.0 
2026-11-06 00:00 UT   05 50 52.1   +02 06 48    19.038   19.714  131.8    2.1   289   40.0 
2026-11-07 00:00 UT   05 50 43.9   +02 05 52    19.033   19.719  132.7    2.1   290   40.0 
2026-11-08 00:00 UT   05 50 35.5   +02 04 57    19.027   19.724  133.6    2.1   291   40.0 
2026-11-09 00:00 UT   05 50 26.9   +02 04 03    19.021   19.729  134.5    2.1   292   40.0 
2026-11-10 00:00 UT   05 50 18.2   +02 03 10    19.016   19.734  135.4    2.0   292   40.0 
2026-11-11 00:00 UT   05 50 09.4   +02 02 18    19.011   19.739  136.3    2.0   293   40.0 
2026-11-12 00:00 UT   05 50 00.4   +02 01 26    19.006   19.744  137.1    2.0   294   40.0 
2026-11-13 00:00 UT   05 49 51.3   +02 00 35    19.001   19.749  138.0    1.9   295   40.0 
2026-11-14 00:00 UT   05 49 42.0   +01 59 46    18.997   19.754  138.9    1.9   296   40.0 

    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.