C/2018 EN4 (NEOWISE)
ephemeris date magn radius delta ra dec elong phase PA
Nearest approach3 Mar 201820.21.887 AU1.249 AU06h44m-13°02'114.3°28.6°76°
Perihelion1 Jun 201818.81.461 AU1.990 AU07h45m+46°16'45.0°29.4°74°
Today29 Mar 202444.714.879 AU15.513 AU21h38m-21°11'49.1°2.9°245°
C/2018 EN4 (NEOWISE)- 2024-03-29
astro.vanbuitenen.nl


 
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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.)

The orbital elements of C/2018 EN4 (NEOWISE) are:

            e (Eccentricity)                : 0.9183290
            q (Perihelion distance)         : 1.4607020
            i (Inclination)                 : 81.99010
            Ω (Longitude of ascending node) : 136.13300
            ω (Argument of perihelion)      : 35.00110
            L (Longitude of perihelion)     : 141.70593
            B (Latitude of perihelion)      : 34.61061
            T (Time of perihelion passage)  : 2458271.12970
            P (Orbital period in years)     : 75.64

            Epoch                           : 2023 Sep 24
            Reference                       : MPC114602

            Classification(s):              : Nearly isotropic; Returning (a < 10000 AU); Halley type (P < 200 years)
        

The light curve chart below shows the estimated development of the comet's magnitude. Blue and black dots are visual and photometric CCD observations respectively from COBS or the MPC. The gray curve is based on the absolute magnitude and slope parameter as calculated from the original MPEC, or the latest values provided by the MPC (15.00 + 5 log[∆] + 10.00 log[r]), whereas the red curve is being recalculated every 6 hours based on the available COBS/MPC observations (currently 13.80 + 5 log[∆] + 21.31 log[r]).


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.
A more printer-friendly version of the same chart can be found further down this page as well.


The following chart shows the current location of the comet in a smaller, upside-down telescopic field of view.


A printable version of the short-term path of the comet in a field of view that is optimized for (~10x50) binoculars and finderscopes.



Ephemerides:
Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2024-03-29 00:00 UT   21 38 51.4   -21 11 48    15.516   14.877   48.8    2.9   245   44.7 
2024-03-29 08:29 UT   21 38 55.5   -21 11 46    15.513   14.879   49.1    2.9   245   44.7 
2024-03-30 00:00 UT   21 39 02.9   -21 11 41    15.507   14.882   49.7    2.9   245   44.7 
2024-03-31 00:00 UT   21 39 14.2   -21 11 35    15.499   14.886   50.6    3.0   245   44.7 
2024-04-01 00:00 UT   21 39 25.3   -21 11 31    15.490   14.890   51.6    3.0   245   44.7 
2024-04-02 00:00 UT   21 39 36.2   -21 11 27    15.482   14.895   52.5    3.1   246   44.8 
2024-04-03 00:00 UT   21 39 47.0   -21 11 25    15.473   14.899   53.5    3.1   246   44.8 
2024-04-04 00:00 UT   21 39 57.5   -21 11 24    15.463   14.904   54.4    3.1   246   44.8 
2024-04-05 00:00 UT   21 40 07.9   -21 11 24    15.454   14.908   55.3    3.2   246   44.8 
2024-04-06 00:00 UT   21 40 18.1   -21 11 25    15.445   14.913   56.3    3.2   246   44.8 
2024-04-07 00:00 UT   21 40 28.0   -21 11 28    15.435   14.917   57.2    3.2   246   44.8 
2024-04-08 00:00 UT   21 40 37.8   -21 11 32    15.425   14.921   58.2    3.3   247   44.8 


    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.