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	15 Jul 2026	39.9	19.137 AU	19.989 AU	05h46m	+03°59'	32.2°	1.6°	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 9.9 + 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
2026-07-14 00:00 UT   05 45 52.6   +04 00 37    19.991   19.130   31.2    1.6   233   39.9 
2026-07-15 00:00 UT   05 46 04.1   +04 00 07    19.989   19.135   31.9    1.6   234   39.9 
2026-07-15 08:37 UT   05 46 08.2   +03 59 57    19.989   19.137   32.2    1.6   235   39.9 
2026-07-16 00:00 UT   05 46 15.5   +03 59 37    19.987   19.140   32.6    1.6   235   39.9 
2026-07-17 00:00 UT   05 46 26.8   +03 59 07    19.985   19.145   33.4    1.7   236   39.9 
2026-07-18 00:00 UT   05 46 38.0   +03 58 35    19.983   19.150   34.1    1.7   237   39.9 
2026-07-19 00:00 UT   05 46 49.2   +03 58 02    19.980   19.155   34.8    1.7   238   39.9 
2026-07-20 00:00 UT   05 47 00.2   +03 57 28    19.977   19.160   35.6    1.8   239   39.9 
2026-07-21 00:00 UT   05 47 11.1   +03 56 54    19.974   19.165   36.3    1.8   240   39.9 
2026-07-22 00:00 UT   05 47 22.0   +03 56 18    19.971   19.171   37.1    1.8   241   39.9 
2026-07-23 00:00 UT   05 47 32.7   +03 55 42    19.967   19.176   37.8    1.9   242   39.9 
2026-07-24 00:00 UT   05 47 43.4   +03 55 05    19.963   19.181   38.6    1.9   242   39.9 
2026-07-25 00:00 UT   05 47 53.9   +03 54 27    19.959   19.186   39.4    1.9   243   39.9 

    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.