C/2019 D1 (Flewelling)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Perihelion	7 May 2019	14.7	1.592 AU	1.645 AU	22h03m	+21°07'	69.0°	36.3°	259°
Nearest approach	10 Sep 2019	17.4	2.288 AU	1.566 AU	01h13m	+44°09'	124.1°	21.4°	217°
Today	2 May 2026	39.7	18.755 AU	19.458 AU	05h31m	+03°52'	44.6°	2.2°	108°

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)                : 0.9881550
    q (Perihelion distance)         : 1.5920230
    i (Inclination)                 : 34.03920
    Ω (Longitude of ascending node) : 231.70440
    ω (Argument of perihelion)      : 70.66600
    L (Longitude of perihelion)     : 298.75608
    B (Latitude of perihelion)      : 31.88338
    T (Time of perihelion passage)  : 2458611.47430
    P (Orbital period in years)     : 1558.19

    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
2026-05-01 00:00 UT   05 31 06.3   +03 52 06    19.440   18.749   45.6    2.2   107   39.7 
2026-05-02 00:00 UT   05 31 16.3   +03 52 46    19.456   18.754   44.7    2.2   108   39.7 
2026-05-02 02:36 UT   05 31 17.4   +03 52 50    19.458   18.755   44.6    2.2   108   39.7 
2026-05-03 00:00 UT   05 31 26.4   +03 53 24    19.472   18.760   43.9    2.1   108   39.7 
2026-05-04 00:00 UT   05 31 36.5   +03 54 02    19.488   18.765   43.1    2.1   109   39.7 
2026-05-05 00:00 UT   05 31 46.8   +03 54 40    19.503   18.770   42.3    2.1   110   39.7 
2026-05-06 00:00 UT   05 31 57.2   +03 55 16    19.518   18.775   41.5    2.0   110   39.7 
2026-05-07 00:00 UT   05 32 07.8   +03 55 52    19.533   18.780   40.7    2.0   111   39.7 
2026-05-08 00:00 UT   05 32 18.4   +03 56 26    19.548   18.785   39.9    2.0   112   39.7 
2026-05-09 00:00 UT   05 32 29.1   +03 57 01    19.562   18.791   39.1    1.9   113   39.7 
2026-05-10 00:00 UT   05 32 40.0   +03 57 34    19.577   18.796   38.3    1.9   113   39.7 
2026-05-11 00:00 UT   05 32 50.9   +03 58 06    19.591   18.801   37.6    1.9   114   39.7 
2026-05-12 00:00 UT   05 33 02.0   +03 58 38    19.605   18.806   36.8    1.8   115   39.7 

    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.